CAPIConversions API
CAPI sends conversion events directly from your server to the ad platform, bypassing browser-side limitations of pixel tracking.
What does CAPI actually mean?
Conversions API (CAPI), sometimes called 'Server-Side Tracking', is a server-to-server API that sends conversion events directly from your backend to the ad platform. It exists for every major platform: Meta CAPI, TikTok Events API, Google Enhanced Conversions.
CAPI solves the browser-side tracking degradation that hit pixels in 2022+. ITP, cookie deprecation, ad blockers and iOS 14+ ATT all reduce client-side event reliability, sometimes by 40-60%. Server-side events bypass the browser entirely, restoring most of that lost signal.
CAPI is now considered table-stakes for any brand spending more than $10K/mo on Meta. The setup is more complex than a pixel (requires backend integration or a tag manager like Stape, GTM Server, or a Shopify CAPI app) but the conversion uplift typically pays back within the first week. Modern stacks run pixel + CAPI together with deduplication.
Example
A Shopify store fires Meta Pixel on the browser side at checkout, AND sends the same Purchase event from the Shopify backend via CAPI. Meta deduplicates the events and uses the most reliable signal for attribution.
When it matters
CAPI restores attribution signal lost to browser tracking changes. Most performance teams report 15-30% reported-ROAS uplift after enabling CAPI alongside the pixel.
Related terms
Pixel
A pixel is a JavaScript snippet on your website that sends user behavior events (pageview, add-to-cart, purchase) back to ad platforms.
Attribution
Attribution determines which ad touchpoint receives credit for a conversion, using last-click, first-click, time-decay or data-driven models.
ATT
ATT is Apple's iOS opt-in framework: apps must ask permission before tracking users across other apps and websites.
SKAdNetwork
SKAdNetwork is Apple's privacy-preserving framework for mobile attribution. It provides aggregated, delayed conversion data without exposing user IDs.
Advantage+
Advantage+ is Meta's AI-driven campaign suite (Shopping, App and Sales) that automates audience, placement and budget decisions.
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