Glossary/Adtech & Programmatic/Ad Tag
Adtech & Programmatic
Ad Tag
A snippet of code placed on a page, app, or in a player that calls an ad server to request and display an ad.
By Brandon Mina·CEO, BrandPilot AI·Updated November 2026
Short answer
An ad tag is a snippet of code placed on a web page, in an app, or in a video player that calls an ad server to request and display an ad. Tags pass information like ad size and placement. In video, VAST tags deliver ads to players. Faulty tags cause delivery errors and reporting discrepancies.