Full Answer

Facebook Conversions API sends purchase, add-to-cart, and other conversion events directly from your server to Meta's servers, bypassing browser-based limitations. Unlike the Meta Pixel, which runs in the browser where ad blockers and iOS privacy restrictions can block it, CAPI transmits data server-to-server with enriched customer identifiers—hashed emails and phone numbers that Meta matches against logged-in users. This closes cross-device attribution gaps. Meta recommends running both Pixel and CAPI simultaneously with event deduplication to maximize data quality without double-counting.