Digital Video Ad Serving Template (VAST)

Last updated: April 16, 2024

Released for Public Comment!

The VAST CTV Addendum 2024 is in public comment from April 16, 2024 to May 17, 2024. The addendum includes extensions that retrofit VAST versions 2.0 and 3.x with vital updates for ad decisioning use cases, measurement, interactive video ads, high resolution media files, and an evolving list of VAST macros. 

Please download the PDF and provide feedback by May 17, 2024 to support@iabtechlab.com.

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About VAST

VAST is a Video Ad Serving Template for structuring ad tags that serve ads to video players. Using an XML schema, VAST transfers important metadata about an ad from the ad server to a video player. Initially launched in 2008, VAST has since played an important role in the growth of the digital video marketplace.

The early days of video consisted mostly of shared videos and other user-generated content. Success in monetizing this content with ads has produced the resources to improve the digital video marketplace. The resources below offer more details. Please send questions or comments to support@iabtechlab.com.

VAST Version History

VersionRelease Date

VAST Addendum

Supports APIs that enable registering event URLs, includes attribute to identify URLs for potential attribution reporting.


July 2023
VAST 4.3 December 2022

VAST 4.2

Secure Interactive Media Interface Definition (SIMID) – the replacement for VPAID for interactive use cases and a few other minor updates.

June 2019

VAST 4.1

Updates for Improved Ad Verification, Ad Creative Measurement, Server-Side Ad Insertion and Integration of Audio Advertising

August 2017

VAST 4.0
January 2016

VAST 3.0
July 2012

VAST 2.0
March 2012
VAST 1.0No longer supported