Conversions API
The server-side pipe that keeps measurement alive when the browser pixel goes quiet.
- Type
- server-side event API
- Restores
- signal lost to ATT and cookies
- Versus pixel
- not blocked by the browser
- Needs
- matching and consent
Forms & parts of speech
Why server-side became necessary
Browser-based tracking pixels are increasingly blocked or degraded — by ad blockers, Apple's tracking limits, and the decline of third-party cookies. Events that used to fire reliably from the browser now go missing.
The Conversions API, often called CAPI, sends those events directly from your server to the ad platform. Because it does not depend on the browser, it captures conversions the pixel alone would lose, restoring measurement and optimisation signal.
How to use it responsibly
CAPI is usually run alongside the pixel, with deduplication so a conversion seen by both is counted once. The richer, more reliable signal also improves the platform's ability to optimise delivery, not just reporting.
It must be done with consent and proper data handling — sending hashed customer information server-side carries privacy obligations. Done well, CAPI is the durable measurement backbone for a post-cookie, post-ATT world.
Adding the Conversions API to send purchase events server-side, deduplicated against the pixel, recovers the missing conversions. Reported numbers climb back toward actual sales, and the platform's optimisation improves because it finally sees most of the outcomes again.
Benchmarks
CAPI's signal recovery varies by setup and browser mix. Measure the lift in matched conversions against your pixel-only baseline rather than a generic figure.
Ranges are illustrative; every published figure is cited from a named public source or labelled “RGM analysis.”
Synonyms & antonyms
Synonyms
Antonyms
Usage trends
Search interest for this term over the last five years:
Common questions
- What is the Conversions API?
- A server-to-server connection that sends conversion events directly to ad platforms, capturing data that browser pixels lose to ad blockers, ATT, and cookie restrictions.
- Why do I need CAPI if I have a pixel?
- Browser pixels increasingly miss events. CAPI runs server-side alongside the pixel, with deduplication, to recover lost conversions and improve platform optimisation.
- Does the Conversions API have privacy obligations?
- Yes. Sending customer data server-side requires consent and proper handling, including hashing identifiers, so it must be implemented carefully.
Related tools & calculators
Resources & people to follow
- referenceMeta — Conversions API documentation
- referenceRGM analysis — CAPI implementation patterns
Curated, non-competitor resources verified per term.