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VAST Inspector
Analyze Video Ad Serving Template (VAST) tags
What is VAST?
VAST (Video Ad Serving Template) is an IAB standard that provides a universal XML schema for serving video ads. It enables video players to communicate with ad servers and display video advertisements with tracking capabilities.
Frequently Asked Questions
What is VAST 4.x?
VAST 4.x is the latest major version of the IAB video ad serving standard, adding support for Mezzanine files, universal ad IDs, and improved server-side ad insertion (SSAI).
How do I fix a VAST 301 error?
A VAST 301 error means "Timeout of VAST URI". Check if the ad tag URL is correct and if the ad server is responding within the player timeout limit.
Can I use VAST with HTML5 video players?
Yes, most modern HTML5 video players like Video.js, JW Player, and Radiant Media Player have built-in support for VAST.
Common VAST Errors
- •Missing MediaFiles: InLine ads must have at least one media file
- •Invalid XML: Malformed XML structure or encoding issues
- •Broken Media URLs: Media files return 404 or wrong content type
- •Too Many Wrappers: Excessive wrapper redirects (max 5 recommended)