analytics-dictionary / tool overview / tracking & measurement

Google Tag Manager

Google Tag Manager is a free tag management system for deploying and managing tracking tags on websites and apps.

Written by Reflective Data experts · updated Oct 5, 2026

GTM lets you add and change tags, triggers and variables from a web interface. It supports web containers in the browser and server containers for server-side tagging.

It is most effective with a clean data layer and good governance. Common problems include duplicate tags, unclear naming and tags that slow the site down.

Consent Mode Data layer Server-side tagging Tag manager

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We build clean tag manager set-ups, data layers and server-side tagging. Google Tag Manager services → · Audits

Reporting identity

Reporting identity is the setting that decides how GA4 recognises users across sessions and devices in…

intelligent-tracking-prevention.md

Intelligent Tracking Prevention (ITP)

ITP is Safari technology that limits cross-site tracking and shortens the lifetime of some cookies.

google-signals.md

Google signals

Google signals is a GA4 feature that uses data from signed-in Google users who consented to…

firebase.md

Firebase

Firebase is Google app development platform, which includes analytics, crash reporting, remote config and more.

conversions-api.md

Conversions API

A conversions API sends conversion events from your server directly to an ad platform, such as…

channel-grouping.md

Channel grouping

Channel grouping organises traffic sources into marketing channels such as organic search, paid search, email and…

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