What it does
Instead of hard-coding every pixel and tag into the site, you install the GTM container once and manage tags, triggers, and variables inside it. That means faster changes, versioning, and one place to govern how your pixel, conversion tags, and analytics fire.
Client-side and server-side
GTM runs client-side in the browser and also as a server-side container, which is more resilient to blockers and cookie limits. Getting the consent order right (defaults before tags, via Consent Mode) is a common source of measurement bugs.
Common questions
What is Google Tag Manager used for?
Deploying and managing tracking tags, pixels, and conversion tags through one container without editing site code for each change, with versioning and centralized control.
Is Google Tag Manager the same as Google Analytics?
No. GTM is a tag-deployment tool; Google Analytics is a measurement product. GTM is often used to deploy Analytics and ad pixels, but they are separate systems.