# Server-Side Tagging

> Firing conversions to ad platforms from a server via their Conversion APIs — the server-side equivalent of a client-side browser tag — so ad blockers, iOS limits, and cookie loss can't drop the delivery.

Server-side tagging fires your conversions to ad platforms from a server — through each platform's [Conversion API](/glossary/conversion-api) — instead of from a client-side browser pixel. Because the delivery happens server-to-server, ad blockers, privacy browsers, iOS App Tracking Transparency, and cookie-lifetime limits can't drop it on the way out. The term was coined by Google Tag Manager: GTM originally loaded tags client-side, then added a server-side container that fires tags from a server — hence "server-side tagging."

## Why Server-Side Tagging is outbound, not inbound

Server-side tagging is the **out** side of going server-side: AnyTrack pushes an enriched, deduplicated conversion to every connected ad platform. It is the counterpart to [Server-Side Tracking](/glossary/server-side-tracking), which is the **in** side — capturing a conversion from another server into AnyTrack. The full chain is *server-side tracking in, server-side tagging out*.

## How AnyTrack uses Server-Side Tagging

AnyTrack performs server-side tagging for you: connect an ad platform in the Integration Catalog and AnyTrack wires up its Conversion API automatically — there is no GTM server container to run or per-event mapping to maintain. Because every event is first stored and attributed in the Data Store, AnyTrack enriches each conversion (resolved identity, recovered click IDs, hashed PII) and deduplicates it against the browser pixel by a shared event ID before delivery. A stateless forwarder can't recover attribution or deduplicate retroactively the way a stateful store can. Delivering to ad platforms via the Conversion API requires a paid plan (Starter and up).

## Server-Side Tagging vs Server-Side Tracking

- [Server-Side Tracking](/glossary/server-side-tracking) — the inbound counterpart: tracking captures conversions *into* AnyTrack; tagging delivers them *out* to ad platforms.
- [Conversion API](/glossary/conversion-api) — the platform endpoint (the channel); server-side tagging is the practice of firing to it from a server.
- [Tracking Tag](/glossary/tracking-tag) — the client-side counterpart that fires to ad platforms from the browser; the recommended setup runs both.