Referrer & traffic-source reference: where visits come from

Reddit can be a strong traffic source, but a large share of it is invisible to referrer-based analytics: links opened in the Reddit mobile app, privacy settings, and link shorteners strip or hide the referrer. This page explains what a Reddit referrer means and how to measure Reddit reliably with UTM tags.

Direct traffic is the bucket analytics uses when no referrer is available. It includes genuine type-ins and bookmarks, but also a large share of visits whose referrer was stripped — app opens, HTTPS-to-HTTP transitions, shorteners, and privacy settings. Treating 'direct' as a single intent is the classic analytics mistake.

Links posted on X (formerly Twitter) are wrapped by the t.co redirector, and a large share of clicks happen inside the X mobile app's in-app browser. Both factors mean the web referrer is frequently absent or shows only t.co, so genuine X visits often land in direct. UTM tags are the reliable way to attribute them.

LinkedIn is a common B2B traffic source, but its lnkd.in link shortener and the in-app browser used on mobile frequently strip the web referrer. Visits then land in direct, undercounting LinkedIn. Because LinkedIn audiences often matter for B2B attribution, UTM tagging is the reliable way to measure them.

Facebook passes outbound clicks through an l.facebook.com redirect and frequently opens links in its in-app browser, both of which can strip the web referrer. The result is that genuine Facebook visits often appear as direct. UTM tags are the dependable way to attribute Facebook-driven traffic.

Instagram concentrates outbound traffic in a single link-in-bio, and almost all clicks happen inside its in-app browser, which typically does not pass a web referrer. As a result, Instagram visits overwhelmingly land in direct. UTM tagging is essential to measure Instagram at all.

YouTube drives outbound traffic primarily through description links, cards, and end screens. On the web these often arrive with a youtube.com referrer, but links opened from the mobile app can lose it. UTM tags make YouTube measurable whether or not the referrer survives.

Quora drives traffic through links embedded in answers. On the web these frequently arrive with a quora.com referrer, so Quora is often more visible in referrer reports than app-heavy social platforms. UTM tags still help attribute Quora consistently across contexts.

Pinterest pins link out to source pages and can drive steady long-tail traffic over time. On the web these often arrive with a pinterest.com referrer, while app opens may strip it. UTM tags make Pinterest measurable across both contexts.

Visits from Google organic search arrive with a google.com referrer, but the query string no longer carries the keyword: Google moved organic search behind HTTPS and reports keyword '(not provided)'. To see which queries drove clicks, Google Search Console is the authoritative source, not the analytics referrer.

Visits from Bing organic search arrive with a bing.com referrer. As with Google, the analytics referrer identifies the source but not the underlying query. Bing Webmaster Tools is the authoritative place to see the searches, impressions, and clicks that drove Bing traffic.

DuckDuckGo is built around privacy, and it applies a strict referrer policy: visits originating from DuckDuckGo searches typically carry no query, and in some configurations little or no referrer reaches your site. This is intentional, not a measurement bug.

Hacker News links typically arrive with a news.ycombinator.com referrer, and the traffic is characteristically spiky: a front-page story can drive a large burst that fades quickly. UTM tags help when you are driving a specific campaign rather than relying on organic submissions.

Product Hunt traffic is dominated by launch-day spikes: a successful launch can send a concentrated burst of visits carrying a producthunt.com referrer, which then tapers. UTM tags on launch links make the campaign measurable beyond the raw referrer.

GitHub drives traffic through links in READMEs, profiles, and repository pages, typically arriving with a github.com referrer. The audience skews technical, which can matter for how you interpret the visits. UTM tags help attribute GitHub links you control.

Clicks from an email newsletter almost never carry a web referrer, because email clients do not send one the way browsers do. As a result, newsletter traffic lands in direct unless the links are tagged. For newsletters, UTM tagging is not optional — it is the only reliable attribution path.

Email clients vary — webmail in a browser versus native desktop and mobile apps — but in practice they rarely pass a usable web referrer to your site. Understanding this behaviour explains why email clicks land in direct and why UTM tagging is the dependable way to attribute them.

Links shared in messaging apps such as WhatsApp, Telegram, and similar tools almost always reach your site with no web referrer. These private shares are a core form of dark social: real, often high-intent traffic that referrer reports cannot attribute. UTM tags are the only reliable measure.

Dark social describes sharing that happens through private channels — messaging apps, email, copied links — where no referrer reaches your site. These visits are real but unattributed, so they inflate the direct bucket. UTM tagging on your own links is the practical way to expose some of it.

Unknown referrer describes the case where a referrer is present but cannot be matched to a known source — it may be malformed, from an obscure domain, or a value the normaliser does not recognise. The honest approach is to bucket it as unknown rather than force-fit it to a familiar channel.

TikTok concentrates outbound traffic in a single link-in-bio and opens links inside its in-app browser, which typically does not pass a web referrer. As a result, TikTok-driven visits overwhelmingly arrive without a tiktok.com referrer and land in direct. UTM tags on link-in-bio destinations are the practical way to attribute TikTok at all.

WhatsApp is a private messaging channel: when a link shared in a chat is tapped, it opens in a context that does not pass a web referrer. WhatsApp-driven visits are therefore a core form of dark social, arriving in the direct bucket with no source. UTM tags on the links you publish are the only reliable way to measure them.

Telegram drives clicks from channels, groups, and direct chats, and its in-app browser typically does not pass a web referrer. Telegram-driven visits therefore arrive as dark social in the direct bucket. Channel owners can tag the links they post with UTM parameters to make the traffic measurable.

Discord drives traffic from links posted in servers and direct messages. Depending on whether a link opens in the desktop client, the mobile app, or an external browser, a discord.com referrer may or may not reach your site. Community-driven visits often land in direct, so UTM tags on shared links keep the channel measurable.

Slack is a common B2B sharing channel. When a link is posted, Slack's unfurl service fetches it to build a preview — a bot request, not a human visit — while a human click may open in the Slack desktop or mobile app and pass little or no referrer. Distinguishing the unfurl from the human click matters, and UTM tags keep human Slack traffic measurable.

Medium drives traffic from articles and profile links, typically arriving with a medium.com referrer on the web. The wrinkle is publishing strategy: content syndicated to Medium with a canonical tag pointing back to your site, or custom-domain publications, can change which domain appears as the referrer. UTM tags keep attribution consistent across these setups.

Substack is a hybrid newsletter-and-web platform. Links clicked from the Substack website or app commonly pass a substack.com referrer, but links clicked from the email edition usually send no referrer at all — like any email. Attribution therefore splits by reading context, and UTM tags are the way to capture both halves.

The fediverse microblogging network is decentralised: there is no single canonical host, but thousands of independent instances, each on its own domain. Web reads commonly pass that instance's domain as the referrer, so this traffic is often identifiable yet spread across many hosts. Recognising the federation pattern is key to attributing it.

Bluesky is a growing social network whose primary web client lives at bsky.app. Links clicked from the web commonly pass a bsky.app referrer, so Bluesky traffic is often identifiable. As with any platform, app and client contexts can reduce the referrer, so UTM tags keep attribution consistent.

Threads is an app-first social platform where most engagement happens in the mobile app. Links tapped there typically open in an in-app browser that does not pass a web referrer, so Threads-driven visits frequently land in direct. UTM tags are the dependable way to attribute Threads traffic.

Twitch drives outbound traffic mainly through channel panels below the stream and links in chat. On the web these commonly pass a twitch.tv referrer, while mobile-app opens can strip it. UTM tags on panel links make streamer-driven traffic measurable across contexts.

Stack Overflow drives traffic from links in questions, answers, and profiles, almost always read on the web, so a stackoverflow.com referrer is commonly present. The audience skews technical and intent-driven. Referrer loss is minimal compared with app-first platforms, though UTM tags still help for links you control.

Wikipedia drives referral traffic from external links in article reference sections, which arrive with a wikipedia.org referrer on the web. Those links carry rel=nofollow, which affects how search engines treat the link — not whether real visitors click through. The traffic is genuine and often high-intent.

Google Discover is a personalised mobile content feed, separate from search results. Visits it drives can arrive with a google.com referrer or, from the Google app, with the referrer reduced or absent, making Discover hard to isolate in analytics. Google Search Console reports Discover performance directly, and is the authoritative source.

Google News drives traffic from its news.google.com web surface and from the Google News mobile app. Web clicks commonly pass a news.google.com referrer, while app opens can reduce or omit it. Recognising the app-versus-web split is key to attributing Google News traffic correctly.

Baidu is the dominant search engine in mainland China, so a baidu.com referrer typically signals organic search from a Chinese-language audience. As with Google, the referrer identifies the source but not the query; Baidu's own webmaster platform is where query-level data lives. The China context also shapes which other engines you may see.

Yandex is a leading search engine in Russia and is used across several neighbouring regions. A yandex referrer — on yandex.ru, yandex.com, or another regional domain — typically signals organic search from that audience. The query is not in the referrer; Yandex Webmaster is the source for query-level data.

Naver is the dominant search portal in South Korea, and a naver.com referrer typically signals a Korean-language audience. Naver is more than a search engine — its blog, cafe, and curated content ecosystem drives much of its referral traffic, so attribution differs from a pure search engine. Naver's own webmaster tools report query and indexing data.

Ecosia is a search engine that serves results from a Bing-powered index and is known for an environmental brand position. An ecosia.org referrer signals organic search from Ecosia, distinct from Bing itself even though the underlying index is shared. Recognising Ecosia as its own source keeps the channel visible.

A self-referral happens when your own domain shows up as the referrer for a visit, which usually means a session broke and restarted mid-journey. Common causes include cross-subdomain navigation, redirect chains, and third-party payment or auth hops that return to your site. The fix is to exclude your own domains so internal navigation is not counted as a new source.

Referrer spam injects fake referrer domains to lure operators into visiting a promoted site, while ghost referrals never touch your server at all — they are fabricated hits sent straight into measurement endpoints. Both pollute source reports with traffic that is not real. Recognising the pattern and filtering it keeps your data trustworthy without ever visiting the spam domains.

When a visit carries both a referrer and UTM campaign parameters, most analytics treat the explicit UTM source as authoritative over the inferred referrer. That is usually correct: UTM tags describe intent you set deliberately, while a referrer is whatever the browser happened to send. Understanding the precedence prevents double-counting and mis-attribution.

Referrer-Policy is the web standard that controls how much of the referrer a browser sends with a request. Site owners set it via an HTTP header or a meta tag, and modern browsers default to a privacy-leaning value. Understanding the policy values explains why so many referrers arrive trimmed to the origin or missing entirely.

A long-standing browser rule removes the referrer when navigating from a secure HTTPS page to an insecure HTTP page, to avoid leaking a secure URL into an unencrypted request. With most of the web on HTTPS this is less common than it once was, but it still explains specific cases of missing referrers — and it is a reason to serve your own site over HTTPS.

Tumblr is a microblogging and reblogging network where shared links can drive visits. In analytics these arrive as referrals from tumblr.com or the t.umblr.com redirect host, but mobile-app taps and link-shimming often strip the original post URL, so tagging campaign links is the reliable way to attribute Tumblr traffic.

VK (VKontakte) is a social network widely used in Russian-speaking regions. Shared links can drive visits that appear as referrals from vk.com, often via its away.php outbound redirect. App taps and link wrapping can hide the originating post, so UTM tags are the dependable way to attribute VK traffic.

LINE is a messaging app dominant in Japan, Taiwan, and Thailand. Links shared in chats or LINE's news and timeline features open in its in-app browser, which usually sends no Referer header, so the traffic looks direct. UTM tags are the reliable way to attribute LINE-driven visits.

Vimeo is a video hosting platform favoured by creators and businesses. Links in video descriptions, profile pages, and player overlays can drive visits that appear as vimeo.com referrals. Embedded players and privacy settings can suppress the referrer, so UTM tags are the reliable way to attribute Vimeo traffic.

Apple News is a news aggregation app on Apple devices. Links tapped from articles and channels open in an in-app browser or Safari and frequently arrive with little or no referrer, so the traffic can look direct. UTM tags are the reliable way to attribute Apple News-driven visits.

Feedly is an RSS feed reader where subscribers follow your content and click through to read in full. Web clicks can appear as feedly.com referrals, but mobile-app reads frequently send no referrer, so UTM tags on your feed links are the reliable way to attribute Feedly traffic.

Sina Weibo is a large microblogging platform in China. Links in posts and reposts can drive visits appearing as weibo.com referrals, but its mobile apps and outbound link wrapping often strip the originating post, so UTM tags are the reliable way to attribute Weibo traffic.

Nextdoor is a hyperlocal social network organised by neighbourhood. Links shared in feeds or recommendations can drive nearby visitors who appear as nextdoor.com referrals, but its mobile app often sends no referrer, so UTM tags are the reliable way to attribute Nextdoor traffic.

Lemmy is a federated, open-source link-aggregation network in the fediverse, similar in shape to Reddit. Because it runs across many independent instances, referrals arrive under different instance domains, so UTM tags are the reliable way to unify Lemmy traffic into a single channel.

Digg is a content-curation and link-aggregation site. Links featured on its homepage or in shares can drive bursts of visits appearing as digg.com referrals, but redirects and referrer-policy settings can strip the source, so UTM tags are the reliable way to attribute Digg traffic.

DEV (dev.to) is a community publishing platform for software developers. Links in articles, profiles, and comments can drive technical visitors who appear as dev.to referrals. Canonical-link and feed behaviour can complicate attribution, so UTM tags keep DEV traffic distinct.

Hashnode is a blogging platform for developers, with posts on hashnode.com subdomains and custom domains. Links in articles can drive technical visitors, but custom-domain hosting and canonical links spread referrals across hosts, so UTM tags keep Hashnode traffic unified.

Indie Hackers is a community for founders and bootstrappers building online businesses. Links in posts, milestones, and discussions can drive a focused founder audience appearing as indiehackers.com referrals, and UTM tags keep that high-intent traffic distinct.

Lobsters (lobste.rs) is an invitation-based link-aggregation community focused on computing. A front-page submission can drive a sharp burst of technically literate visitors appearing as lobste.rs referrals, and UTM tags keep that niche channel distinct.

Behance is Adobe's portfolio network for creative professionals. Links in projects, profiles, and the project sidebar can drive a design-oriented audience appearing as behance.net referrals, and UTM tags keep that creative channel distinct.

Dribbble is a community where designers share visual work ('shots'). Links in shot descriptions, profiles, and the profile sidebar can drive a designer audience appearing as dribbble.com referrals, and UTM tags keep that creative channel distinct.

Dailymotion is a video hosting platform. Links in video descriptions and player overlays can drive visits appearing as dailymotion.com referrals, but embedded players can surface the host site instead, so UTM tags are the reliable way to attribute Dailymotion traffic.

Rumble is a video hosting and streaming platform. Links in video descriptions and player overlays can drive visits appearing as rumble.com referrals, but embeds can surface the host site instead, so UTM tags are the reliable way to attribute Rumble traffic.

SoundCloud is an audio streaming platform for music and podcasts. Links in track descriptions, profiles, and embedded players can drive listeners to your site as soundcloud.com referrals, but embeds and apps suppress the referrer, so UTM tags keep SoundCloud traffic attributable.

Spotify is a streaming platform for music and podcasts. Links in podcast show notes or shared from the app typically open with no referrer, because the app and many show-note surfaces strip it, so UTM tags are the reliable way to attribute Spotify-driven visits.

Patreon is a membership platform where creators share posts and links with supporters. Links in posts and creator pages can drive a loyal supporter audience appearing as patreon.com referrals, but app and gated contexts can strip the referrer, so UTM tags keep Patreon traffic attributable.

KakaoTalk is the leading messaging app in South Korea. Links shared in chats or KakaoTalk channels open in its in-app browser, which usually sends no Referer header, so the traffic looks direct. UTM tags are the reliable way to attribute KakaoTalk-driven visits.

Flipboard is a social news-magazine aggregator where users curate articles into magazines. Web clicks can appear as flipboard.com referrals, but the mobile app frequently sends no referrer, so UTM tags are the reliable way to attribute Flipboard-driven visits.

Yahoo Search referrals come from people clicking your page in Yahoo's web results at search.yahoo.com. Yahoo's web results have long been powered by partner search technology, so the experience resembles other engines, but the referrer host is what identifies the source. Like all modern search engines, Yahoo strips the query from the Referer header, so you see the engine but not the keyword.

XING is a professional and business network popular in German-speaking markets (DACH). Web clicks from XING posts and profiles can appear as xing.com referrals, but app and messaging shares often arrive without a referrer, so UTM tags are the reliable way to attribute XING-driven visits.

Pocket is a save-for-later reading service where people queue articles to read on their own schedule. Web reads can appear as getpocket.com referrals, but the apps frequently send no referrer and reads are time-shifted, so UTM tags are the reliable way to attribute Pocket-driven visits.

Analytics platforms do not report every raw referrer separately — they map hosts into channel groups such as organic search, paid, social, referral, email, and direct. Understanding the default rules explains why a click ends up in one bucket versus another, and why a custom source can be misfiled until you adjust the grouping.

Branded traffic is driven by people who already know your name; non-branded traffic comes from people who found you generically. The Referer header cannot tell them apart because modern search engines strip the query, so the split must be approximated using search-console keyword data and the entry context, not the referrer alone.

In a single-page app, the History API changes the URL and view without a full page load, so the browser does not send a new Referer header for each route. The header reflects the original entry point, not the internal navigation, which means SPA analytics must capture referrer and entry data at first load and track route changes separately.

AOL Search referrals come from people clicking your page in AOL's web results at search.aol.com. AOL is a long-standing portal whose web results are supplied by a search partner, but the referrer host identifies the source. Like other engines, AOL strips the query from the Referer header, so you see the portal but not the keyword.

Ask.com referrals come from people clicking your page in Ask's web results at ask.com. Ask is a long-running question-and-answer oriented portal whose web results are supplied by a search partner, but the referrer host identifies the source. Like other engines, Ask strips the query from the Referer header.

Startpage is a privacy-focused search engine that returns Google-sourced results without tracking the user. Because privacy is its core design, Startpage typically does not pass a Referer header to the destination, so its clicks usually arrive as direct or unknown rather than a startpage.com referral.

Qwant is a European, privacy-oriented search engine based in France that does not track its users. Some clicks can appear as qwant.com referrals, but its privacy design and strict referrer policy mean many organic clicks arrive without a referrer and never carry the query, so part of Qwant traffic lives in direct.

Brave Search is a privacy-focused engine with its own independent web index, distinct from Google and Bing. Clicks can appear as search.brave.com referrals, but Brave's privacy posture and strict referrer policy mean some organic clicks arrive without a referrer and never carry the query.

Sogou is a major Chinese search engine, notable for indexing content from within the WeChat ecosystem. Organic clicks reach your site as sogou.com referrals, identifying the engine, but like other engines Sogou strips the query from the Referer header, so you see the source without the keyword.

Seznam is a leading Czech portal and search engine that competes strongly with Google in the Czech Republic. Organic clicks reach your site as search.seznam.cz referrals, identifying the engine, but like other engines Seznam strips the query from the Referer header.

SmartNews is a mobile news-aggregator app that surfaces articles algorithmically across regions. Because it is app-first, most reads open in an in-app browser that does not forward a Referer header, so SmartNews-driven visits commonly arrive as direct, and UTM tags are the reliable way to attribute them.

Inoreader is an RSS and feed-reader service where people subscribe to your feed and read articles in the reader. Web clicks can appear as inoreader.com referrals, but app and mobile reads often send no referrer, so UTM tags are the reliable way to attribute Inoreader-driven visits.

NewsBreak is a US-focused local-news aggregator app that surfaces articles by location. Because it is app-first, most reads open in an in-app browser that does not forward a Referer header, so NewsBreak-driven visits commonly arrive as direct, and UTM tags are the reliable way to attribute them.

WeChat (Weixin) is a dominant Chinese super-app combining chat, Moments, and Official Accounts. Almost all links open in WeChat's in-app browser, which generally does not forward a Referer header, so WeChat-driven visits overwhelmingly arrive as direct, and UTM tags are the reliable way to attribute them.

Viber is a messaging app popular in parts of Europe and Asia, with one-to-one chats, groups, and communities. Links shared in Viber are dark social: chats expose no referrer and in-app opens often send none either, so Viber-driven visits arrive as direct, and UTM tags are the way to attribute them.

Signal is a privacy-focused, end-to-end encrypted messaging app. Links shared in Signal are pure dark social: there is no chat-level referrer, and taps open in the system browser or an in-app view without conveying Signal as the source, so visits arrive as direct and UTM tags are the only way to attribute them.

Snapchat is a mobile-first messaging and Stories app where links are attached to snaps and Stories. Clicks open in Snapchat's in-app browser, which generally does not forward a Referer header, so Snapchat-driven visits commonly arrive as direct, and UTM tags are the reliable way to attribute them.

GitLab referrals come from links in repositories, issues, merge requests, wikis, and snippets on gitlab.com or self-managed instances. A gitlab.com referrer indicates developer-context traffic, though self-hosted GitLab instances use their own domains and links rendered in READMEs can carry restrictive referrer policies.

Bitbucket referrals come from links in repositories, pull requests, and wikis on bitbucket.org, Atlassian's Git hosting service. A bitbucket.org referrer indicates developer-context traffic, often from teams using the broader Atlassian toolset, though referrer policy on rendered pages can send some clicks to direct.

npm referrals come from package pages on npmjs.com, the JavaScript package registry. When your package page links to a homepage, repository, or docs, clicks reach you as npmjs.com referrals — a strong signal of developer interest in your library, though referrer policy can send some to direct.

Gumroad referrals come from creator and product pages on gumroad.com, a platform for selling digital products. Clicks from a Gumroad page or profile can reach your site as gumroad.com referrals, but embedded checkouts and redirects can obscure the path, so UTM tags help keep creator-commerce traffic attributable.

Amazon referrals come from links on amazon.com and its regional domains — product listings, author pages, brand stores, and reviews. Because Amazon operates many country domains and applies referrer policy, the host varies by region and some clicks arrive as direct, so UTM tags help keep marketplace traffic attributable.

A single visit can arrive with both a Referer header and UTM campaign parameters. Most analytics tools let the explicit campaign parameters take precedence over the inferred referrer, because a deliberate utm_source is a stronger signal than a host guess. Knowing the precedence order explains why a tagged link shows your campaign source even when the referrer differs.

When an Android app opens a web URL, it can attach an Intent referrer (EXTRA_REFERRER) indicating which app launched the browser. This is an Android platform mechanism distinct from the HTTP Referer header — some browsers expose it and some do not — so app-originated visits may or may not reveal the launching app, and UTM tags remain the reliable cross-platform signal.

On iOS, a universal link lets a tapped https URL open directly in an installed app instead of the browser. Because the transition skips a normal web navigation, there is usually no HTTP Referer header for the destination, so universal-link visits often arrive as direct and UTM parameters are the reliable way to attribute them.

Link shorteners like Bitly turn a long URL into a short one that issues an HTTP redirect to the destination. Because the redirect hop is a separate origin (and often does not forward a meaningful referrer), shortened-link clicks frequently arrive without revealing where they were actually shared. This page explains the mechanics and why UTM parameters baked into the destination are the reliable way to measure shortened links.

TinyURL is a long-standing link shortener that redirects a short code to a destination URL. Like other shorteners, the redirect hop hides the original sharing context, so TinyURL clicks often appear as the shortener host or as direct traffic. This page covers what the referrer means and why UTM tags on the destination URL are the dependable signal.

ow.ly is the link shortener associated with the Hootsuite social-scheduling platform. Links shortened with ow.ly redirect to the destination, so the referrer often shows the shortener host or nothing — and crucially does not tell you which social network the post ran on. This page explains the mechanics and the UTM approach for scheduled social links.

Etsy is a marketplace for handmade, vintage, and craft goods. When a shop links from its Etsy profile or listings to an external site, those clicks can appear with an etsy.com referrer — but app navigation, link wrapping, and outbound-link handling often strip or mask the source. This page explains what the referrer means and how to tag Etsy-placed links.

eBay is a global marketplace for new and used goods. Links a seller places in listings or a store profile can drive external traffic that sometimes carries an ebay.com referrer, but the eBay app and outbound-link handling frequently strip it. This page explains what an eBay referrer means and how UTM tags keep marketplace-driven visits measurable.

AliExpress is a large cross-border retail marketplace. Outbound links from listings or seller pages can sometimes show an aliexpress.com referrer, but heavy app usage, regional domains, and outbound-link redirects often strip or fragment it. This page explains what the referrer means and how UTM tags keep marketplace traffic measurable.

Shopify powers millions of independent online stores, each on its own domain or a myshopify.com subdomain. A link from one Shopify store to another site shows that store's domain as the referrer — but checkout flows, embedded apps, and the Shop app can break the chain. This page explains what a Shopify-store referrer means and how to tag cross-store and partner links.

Wellfound, formerly AngelList Talent, is a startup jobs and company platform. Links from a company profile or job post to an external site can show a wellfound.com referrer, but app navigation and outbound-link handling often strip it. This page explains what the referrer means and how to tag Wellfound-placed links for reliable attribution.

Glassdoor is a jobs and employer-reviews platform. Links from a company profile or job listing to an external careers site can carry a glassdoor.com referrer, but the Glassdoor app and outbound-link redirects often strip it. This page explains what the referrer means and how UTM tags keep employer-brand traffic measurable.

Crunchbase is a database of companies, funding, and people. A link from a company's Crunchbase profile to its website can carry a crunchbase.com referrer, but referrer-policy trimming and outbound-link handling can reduce it to the bare host or strip it. This page explains what the referrer means and how to tag profile links for reliable attribution.

Douban is a Chinese platform for books, film, music, and interest-group communities. Links shared in Douban groups or reviews can carry a douban.com referrer, but its app and outbound-link handling often strip it. This page explains what a Douban referrer means and how UTM tags keep this traffic measurable.

Naver Cafe is the community-forum service inside South Korea's Naver portal, where members run topic-based groups. Links shared in cafes can carry a cafe.naver.com referrer, but app usage and member-only contexts often strip it. This page explains what a Naver Cafe referrer means and how UTM tags keep Korean community traffic measurable.

Daum Cafe is the long-running community-forum service in South Korea's Daum (Kakao) portal. Links shared in Daum cafes can carry a cafe.daum.net referrer, but app usage and member-only views often strip it. This page explains what a Daum Cafe referrer means and how UTM tags keep this community traffic measurable.

Odnoklassniki (OK.ru) is a social network popular across Russian-speaking regions. Links shared on OK.ru can carry an ok.ru referrer, but its app and outbound-link handling often strip it. This page explains what an Odnoklassniki referrer means and how UTM tags keep this regional social traffic measurable.

Apple Podcasts is a podcast directory and player app. Links in episode show notes are tapped inside the app, and the resulting web visit usually carries no HTTP referrer — so podcast-driven traffic typically appears as direct. This page explains why and how to tag show-notes links so podcast attribution actually works.

Overcast is a popular third-party podcast player for iOS. Show-notes links tapped inside Overcast open in a browser without an HTTP referrer, so podcast traffic from Overcast typically lands as direct. This page explains the mechanics and how UTM tags on show-notes links restore podcast attribution.

Pocket Casts is a cross-platform podcast player. Show-notes links tapped in the app open in a browser without an HTTP referrer, so Pocket Casts podcast traffic typically appears as direct. This page explains the mechanics and how UTM tags on show-notes links make podcast attribution work.

Castbox is a podcast player with a large mobile user base. Links tapped in Castbox show notes open in a browser without an HTTP referrer, so Castbox podcast traffic typically appears as direct. This page explains the mechanics and how UTM tags on show-notes links restore podcast attribution.

Slashdot is a long-running technology news and discussion site. A link that reaches its front page or comments can drive a sharp burst of referral traffic carrying a slashdot.org referrer. This page explains what the referrer means, why such spikes are crawl-like in shape but human, and how UTM tags clarify the source.

Designer News is a community where designers and product people share and discuss links. A submission can drive referral traffic carrying a Designer News referrer, but referrer trimming and app/in-client clicks can reduce or drop it. This page explains what the referrer means and how UTM tags keep design-community traffic measurable.

A referral-exclusion list tells an analytics tool to treat traffic from certain domains — your own site, a payment gateway, an auth provider — not as a new referral but as a continuation of the existing session. Without it, a round-trip through checkout or login can split one visit into several and credit the wrong source. This page explains the mechanism and how to use it.

Modern browsers trim the referrer for privacy: the default policy sends only the origin (scheme + host) when navigating cross-site, not the full path and query. So you often see example.com rather than the specific page that linked to you. This page explains the default referrer policy, why it exists, and why UTM parameters are unaffected.

When a journey crosses between domains you own — a marketing site to an app subdomain, or a multi-domain checkout — the original source can be lost: the second domain sees the first as the referrer (a self-referral) and the inbound campaign is overwritten. This page explains cross-domain referrer loss and how exclusion lists plus persisted UTM parameters prevent it.

A visitor often touches several sources before converting. First-click attribution credits the referrer that started the journey; last-click credits the one immediately before conversion. The same session can therefore be attributed to different referrers depending on the model — which is why the original inbound source is easy to lose without persisted campaign data. This page explains the distinction and the UTM approach.

ResearchGate is a social network for researchers where publications, profiles, and Q&A threads are shared. Outbound links to your site, dataset, or institutional page can appear as researchgate.net referrals, but profile and feed navigation plus referrer-policy downgrades can collapse the originating page, so UTM tags keep academic referrals attributable.

Academia.edu is a platform where academics upload papers and maintain profiles. Outbound links from a paper page, profile, or recommendation can appear as academia.edu referrals, but feed and search navigation plus referrer-policy downgrades often hide the originating page, so UTM tags are the dependable way to attribute the traffic.

SSRN is a repository of working papers and preprints, especially in social sciences, economics, and law. Links from an abstract page, author page, or download page can appear as ssrn.com referrals, but referrer-policy downgrades and download-redirect flows often collapse the originating page, so UTM tags keep the traffic attributable.

Habr is a large Russian-language technology and developer community with articles, hubs, and comment threads. Outbound links in posts or comments can appear as habr.com referrals, but the platform's link handling and referrer-policy downgrades can collapse the originating article, so UTM tags keep developer referrals attributable.

Pikabu is a large Russian-language entertainment and discussion community similar in spirit to a link-aggregator. Links in posts and comments can appear as pikabu.ru referrals, but outbound link wrapping and referrer-policy downgrades often collapse the originating post, so UTM tags keep the traffic attributable.

Tistory is a popular Korean blogging platform operated by Kakao, where each blog lives on a subdomain of tistory.com. Links in blog posts can appear as tistory.com referrals, but referrer-policy downgrades and subdomain handling can blur which blog or post sent the click, so UTM tags keep blog referrals attributable.

Ameblo (Ameba Blog) is a large Japanese blogging platform run by CyberAgent, popular with creators and celebrities. Links in posts can appear as ameblo.jp referrals, but the platform's app, feeds, and referrer-policy downgrades often collapse the originating post, so UTM tags keep Japanese blog referrals attributable.

note.com is a Japanese publishing and creator platform where writers post articles, paid notes, and magazines. Links in articles can appear as note.com referrals, but app navigation and referrer-policy downgrades often collapse the originating article, so UTM tags keep writer-driven referrals attributable.

Mercado Libre is the leading e-commerce marketplace across Latin America, operating country-specific hosts such as mercadolibre.com.ar and mercadolivre.com.br. Links from listings, stores, or seller pages can appear as referrals from these hosts, but app navigation and outbound redirects often collapse the originating listing, so UTM tags keep commerce referrals attributable.

Walmart.com is a large U.S. retailer and third-party marketplace. Links from product pages, seller pages, or content can appear as walmart.com referrals, but app navigation and outbound redirects often collapse the originating page, so UTM tags keep retail referrals attributable.

Target.com is a major U.S. retailer whose product pages, guides, and content can link out to brand sites. Such clicks can appear as target.com referrals, but app navigation and outbound redirects often collapse the originating page, so UTM tags keep retail referrals attributable.

The Stack Exchange network includes more than a hundred Q&A communities such as superuser.com, serverfault.com, askubuntu.com, and many topic sites under stackexchange.com. Answer links to your site can appear as referrals from any of these hosts, so grouping them as one network channel, and tagging links, keeps the traffic attributable and consistent.

Spiceworks is a community and resource hub for IT professionals, with forums, how-to articles, and product discussions. Links in threads or articles can appear as spiceworks.com referrals, but referrer-policy downgrades and outbound handling can collapse the originating thread, so UTM tags keep IT-pro referrals attributable.

Kuaishou is a major Chinese short-video platform. Outbound taps from videos or profiles almost always happen inside the app, so most clicks arrive with no Referer and land in direct or unknown traffic, making UTM tags the only reliable way to attribute Kuaishou traffic.

Likee is a global short-video app. Outbound taps from videos or profiles happen inside the app, so most clicks arrive with no Referer and fall into direct or unknown traffic, making UTM tags the dependable way to attribute Likee traffic.

When a page is served through an AMP cache, a click onward to your site may carry a Referer pointing at the cache host (such as a google.com AMP path) rather than the publisher who linked you. Understanding the cache hop, and tagging links, keeps AMP-mediated referrals attributable to the real source.

Clicks from paid ads often pass through an ad network's click-measurement server before reaching your site, so the Referer may point at a tracking or redirect host rather than the publisher where the ad ran. Because referrers from paid placements are unreliable, UTM parameters are essential to attribute ad traffic correctly and keep it separate from organic referrals.

When a reader clicks a link inside a PDF, the originating context is a document viewer, not a web page, so the click commonly arrives with no Referer or an opaque one. Native readers, in-app viewers, and downloaded files all behave differently, which is why links inside PDFs need UTM tags to stay attributable.