WAVE accessibility crawler
WAVE is a web accessibility evaluation tool from WebAIM that analyses pages for accessibility and WCAG issues, available as a hosted checker, browser extension, and API. Its hosted and API modes fetch a page to evaluate its accessibility and report errors and alerts. It is an accessibility-evaluation tool, typically run on pages you want to test, rather than a search engine indexing content.
What this means
WAVE, developed by WebAIM at Utah State University, evaluates a web page for accessibility problems and presents errors, alerts, and structural information. It is offered as a hosted online checker, a browser extension, and a WAVE API for programmatic testing.
In its hosted and API modes, WAVE fetches the page server-side to evaluate it, which can appear in your logs. This is accessibility evaluation, not search indexing.
How it identifies itself
WAVE hosted and API fetches originate from WebAIM/WAVE infrastructure and may carry a WAVE-identifying user-agent. The browser-extension mode runs in the user's own browser and may not generate distinct identifiable server requests. Match on the WAVE/WebAIM identity for hosted and API checks.
As with any tool, the user-agent is a claim and can be copied. Correlate with evaluations you initiated where authenticity matters.
- Operator: WebAIM (WAVE accessibility evaluation tool)
- Modes: hosted checker, browser extension, WAVE API
- Hosted/API modes fetch the page server-side
robots.txt considerations
Accessibility evaluation is generally run against pages you want to test, so you may allow it deliberately. Where the hosted fetcher exposes a documented token, target it in robots.txt to express a preference.
robots.txt is honoured by compliant crawlers and is not an access control. Restricting the evaluator would only limit your own accessibility testing.
How it appears in analytics and logs
A WAVE request means an accessibility evaluator fetched your page to flag WCAG issues, usually a check you or a tester initiated. It is accessibility-testing bot traffic, not a human visit and not a search-index crawl.
Diagnostic use case
Recognise WAVE accessibility checks in logs, confirm they correspond to your own evaluations, and distinguish accessibility analysis from search indexing.
What WebmasterID can help detect
WebmasterID classifies WAVE checks server-side as accessibility-testing bot traffic and surfaces them on the bot-intelligence surface, so evaluations stay separate from human analytics.
Common mistakes
- Mistaking an accessibility evaluation for a search or hostile crawl.
- Assuming the browser-extension mode always produces identifiable server requests.
- Counting accessibility-check fetches as human visits in analytics.
Privacy and accuracy notes
Identification uses only the request user-agent and evaluation context. No visitor identity is involved. WebmasterID records the fetch as a bot event, separate from human analytics, and never attaches it to a profile.
Related pages
- axe accessibility scanner
axe is an open-source accessibility-testing engine from Deque Systems, embedded in browser extensions, CI pipelines, and tools that evaluate pages against WCAG accessibility rules. When run in an automated or hosted mode it fetches and renders a page to analyse its accessibility, rather than indexing content for search. It typically runs on your own pages, on demand, as part of accessibility QA.
- Lighthouse and PageSpeed Insights fetchers
Lighthouse is Google's open-source page-quality auditing tool, and PageSpeed Insights is the hosted service that runs Lighthouse audits and reports field and lab performance data. Both fetch a page on demand to measure it, not to index it for search. Their fetches are user-triggered performance audits and appear in logs as a single page load with related resource requests, not a crawl.
- Web-performance fetchers overview
Web-performance tools — Lighthouse, PageSpeed Insights, GTmetrix, WebPageTest and similar — load a page on demand to measure speed, rendering, and resource behaviour. They are neither search crawlers nor human visitors: they are user-triggered measurement automation. Reading them correctly keeps performance audits out of audience metrics and out of search-crawl coverage.
- Website observability
See accessibility evaluators reaching your site, recorded server-side.
Sources and verification notes
- WebAIM — WAVE accessibility evaluation toolHosted accessibility checker, browser extension, and API documented.
Last reviewed 2026-06-24. Facts are checked against primary/official sources where available; uncertain specifics are marked “Data not yet verified” rather than guessed.