Conversions API is Meta's server-to-server event-matching system, sending conversion data directly from an advertiser's server to Meta to supplement browser and app tracking lost to ad blockers and privacy restrictions.
Conversions API sends web, app, and offline event data straight from an advertiser's server to Meta, running alongside the browser-based Meta Pixel rather than replacing it. Where the Pixel depends on a browser loading a script and cookies surviving deletion, Conversions API events travel server-to-server and hold up against ad blockers, iOS tracking restrictions and cookie-consent gaps.
Meta explicitly recommends running Pixel and Conversions API together — deduplicated by event ID — because each one catches conversions the other misses. On iOS specifically, Conversions API works alongside SKAdNetwork rather than replacing it: SKAdNetwork handles Apple's privacy-preserving postback attribution for app installs, while Conversions API covers web and server-side events.
Setup usually runs through a server-side tag manager or a direct server integration, matching hashed customer data (email, phone, external ID) to Meta's systems for attribution and optimization.
Conversions API is the difference between an attribution stack that degrades gracefully under privacy restrictions and one that goes dark. Accounts running Pixel-only measurement lose a meaningful share of conversion events to blockers and cookie limits; Conversions API recovers a chunk of that signal server-side, which is why it now sits at the center of most post-iOS 14 Meta measurement setups.
