What add-to-cart rate is and how to compute it
Add-to-cart rate is the percentage of sessions, or unique visitors, in which at least one item was
added to the cart. It sits in the funnel between a product view and the final purchase.
ATC rate = (sessions with an add to cart / all sessions) × 100%
Example: 1,200 sessions with an add out of 12,000 → 10%
It is computed two ways: by session (the standard) and by unique visitor. The session figure is
higher, because one person can add items across several visits.
Where it sits in the funnel
Traffic → product view → add to cart → checkout → payment
↑ ATC rate ↑ cart-to-checkout rate
All three ratios deserve reading together. A high add-to-cart rate with a low cart-to-checkout rate
points at the cart or the checkout, not at the product page.
What moves add-to-cart rate
| Factor | Effect |
|---|---|
| Image and description quality | Direct: uncertainty means no add |
| Personalized listing order | Indirect: relevant items higher means more adds |
| Similar items widget on the product page | Direct: widens the choice without losing the visitor |
| Page load speed | Direct: every additional second costs conversion |
| Reviews and ratings | Direct: social proof removes doubt |
As a proxy metric in A/B tests
Add-to-cart rate is a popular instrument for testing hypotheses quickly. Because it occurs three to
five times more often than a purchase, a significant sample arrives sooner.
Important: a rise in add-to-cart rate does not always mean a rise in revenue. After a test with
it as the primary metric, check whether the gain converted into conversion and revenue per visitor.
If it did not, you may be optimising an intent that never completes.