# Conversion API

> An ad platform's server-to-server endpoint for receiving conversions directly from a server — bypassing the browser pixel — which AnyTrack enriches, deduplicates, and delivers automatically.

The Conversion API (industry term; abbreviated **CAPI**) is a server-to-server interface offered by ad platforms — Facebook, Google, TikTok, Microsoft, and others — that lets advertisers send conversion events directly from a server to the ad platform, without depending on a browser pixel. It exists because ad blockers, iOS privacy controls, Safari's Intelligent Tracking Prevention, third-party-cookie deprecation, and consent banners all silently drop pixel events.

## What each platform calls the Conversion API

| Platform | API name |
| --- | --- |
| Facebook / Instagram | Conversions API (CAPI) |
| Google Ads | Enhanced Conversions for Web / Google Ads API |
| TikTok | Events API |
| Microsoft (Bing) | UET Offline Conversions / Conversion API |
| Outbrain | Server-to-Server (S2S) |
| Taboola | S2S Conversions |

The mechanics differ per platform, but the goal is identical: deliver a structured server-side event with hashed user identifiers, an event name, a value, and the parameters needed for attribution and modeling.

## How AnyTrack uses the Conversion API

AnyTrack sits between your funnel and your ad platforms and wires up each platform's Conversion API automatically when you connect the integration — there is no per-event mapping to maintain. Every conversion runs through five steps:

1. **Collect** — the Tracking Tag gathers first-party data client-side; server-side sources (Shopify webhooks, affiliate postbacks, CRM webhooks) are collected directly.
2. **Attribute** — every event is stitched to the original Click ID.
3. **Enrich** — customer data is normalized and hashed with SHA-256 per each platform's spec, with the platform's own click ID and the metadata that drives Event Match Quality.
4. **Deduplicate** — a shared event ID prevents double-counting when the same conversion arrives from multiple sources.
5. **Distribute** — the same enriched event is fanned out in real time to every connected platform's Conversion API.

## How the Conversion API differs from similar terms

- [Tracking Tag](/glossary/tracking-tag) — client-side script vs server-side delivery to ad platforms.
- [Server-Side Tagging](/glossary/server-side-tagging) — the Conversion API is the *channel* (the platform endpoint); server-side tagging is the *practice* of firing to it from a server.
- [Server-Side Tracking](/glossary/server-side-tracking) — the Conversion API delivers conversions *out* to ad platforms; server-side tracking captures them *in* to AnyTrack — opposite directions.
- [Outgoing Webhook](/glossary/outgoing-webhook) — CAPI targets ad platforms with hashed identifiers; an outgoing webhook sends the raw event+attribution payload to any endpoint.
- [Event Match Quality](/glossary/event-match-quality) — a match score for a delivered event, not the delivery channel.