Sample VAST tags
VAST (Video Ad Serving Template) is an IAB Tech Lab XML specification for delivering video ads to a video player. These tags reference samplelib mp4/mp3 samples in MediaFile fields and play out of the box in Google IMA SDK, JW Player, Video.js, Brightcove, or any other VAST-compliant player. Useful for debugging trackers, wrapper chains, skippable, podded (CTV), companion and non-linear creatives.
💡 Click ▶ next to any tag — the official Google IMA test player opens with the tag pre-loaded and video plays in a single click. Handy for quick compatibility checks. Open empty player · VAST specification at IAB Tech Lab
🧠 How VAST works
A VAST tag is an XML document the video player requests from an ad server before playing content. Two types: Inline (contains the creative itself — MediaFile, trackers, clickability) and Wrapper (contains only a redirect to another VAST tag). Wrapper chains are used for mediation between SSPs, exchanges and DSPs — the player unwraps redirects until it reaches the first Inline. Versions: 2.0 (2008), 3.0 (2012, Skippable), 4.0 (2016, Mezzanine + AdVerifications), 4.1 (2018, audio via VAST instead of DAAST), 4.2 (2019, SIMID), 4.3 (2022).