The add_to_cart event
add_to_cart is a GA4 recommended e-commerce event that fires when a visitor adds a product to the cart. It carries the items added plus currency and value. It is a strong mid-funnel intent signal — stronger than a product view — and the denominator for cart-to-checkout and cart-to-purchase analysis.
What this means
add_to_cart is a GA4 recommended retail event sent when a product is placed in the cart. Populate the `items` array with the added products (id, name, price, quantity) and set `currency` and `value` to the monetary worth added. GA4 uses it across shopping-behaviour and funnel reports.
It is a clear intent signal: the visitor has moved from looking to selecting, which is why it anchors much of the e-commerce funnel.
Funnel and value
Read add_to_cart against the steps around it: view_item before, begin_checkout and purchase after. The ratio of add_to_cart to purchase frames overall cart abandonment. Always pair value with currency. If you also fire remove_from_cart, you can net out additions against removals to understand true cart momentum.
- Fires when a product is added to the cart
- Carries items, currency, and value
- Anchors cart-to-checkout and cart-to-purchase analysis
How it appears in analytics and logs
An add_to_cart event means a visitor committed to considering a purchase. Many add_to_cart events with few begin_checkout events point to friction or hesitation at the cart stage.
Diagnostic use case
Measure add-to-cart intent per product, then compare it against begin_checkout and purchase to locate where shoppers abandon.
What WebmasterID can help detect
WebmasterID can record add-to-cart events first-party with item and value context, so cart intent is measurable without third-party e-commerce tags.
Common mistakes
- Sending value without currency.
- Omitting quantity, so multi-unit adds undercount.
- Firing on cart-page views instead of the add action.
Privacy and accuracy notes
add_to_cart describes the product and quantity added, not the shopper. Keep customer identifiers out of the items array and event parameters.
Related pages
- The view_item e-commerce event
view_item is a GA4 recommended e-commerce event that fires when a visitor views a product's detail page. It carries an items array describing the product (id, name, price) plus currency and value. It sits early in the purchase funnel — between browsing a list and adding to cart — and is the foundation for product-level engagement and conversion analysis.
- The begin_checkout event
begin_checkout is a GA4 recommended e-commerce event that fires when a visitor starts checkout. It carries the items in the order plus currency, value, and an optional coupon. It marks the transition from cart to purchase flow and is the entry point for measuring checkout abandonment — the gap between starting checkout and completing a purchase.
- The add_to_wishlist event
add_to_wishlist is a GA4 recommended e-commerce event that fires when a visitor saves a product to a wishlist or favourites. It carries the items saved plus currency and value. It signals interest without immediate purchase intent — a softer signal than add_to_cart — useful for understanding consideration and for products people return to buy later.
- Event Explorer
Inspect cart events and funnels.
Sources and verification notes
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.