The VAST Tag Tester is a free, online tool designed for publishers, agencies, and ad operations professionals to validate and troubleshoot video ad responses. It provides instant parsing and validation of VAST 2.0–4.3 XML tags, ensuring compliance with IAB specifications. This comprehensive tool helps users detect errors, warnings, and broken tracking URLs before they impact live campaigns, thereby preventing lost impressions and revenue.
Key Features:
- Instant XML Parsing: Quickly paste any VAST URL or raw XML to get a structured breakdown in under a second. The tool operates entirely in the browser, eliminating server-side processing delays.
- IAB Spec Compliance: Every attribute and element within the VAST XML is rigorously validated against official VAST 2.0, 3.0, 4.0, 4.1, 4.2, and 4.3 schemas, guaranteeing full adherence to industry standards.
- Tracking Pixel Audit: Extract and verify all impression, click, and quartile tracking URLs. The tester performs real HTTP checks to ensure these pixels resolve correctly, preventing missed billable events.
- VAST Wrapper Chain Support: Automatically resolves VAST wrapper redirects up to 5 levels deep, validating each hop for potential errors or missing attributes to ensure seamless ad delivery.
- Media File Analyzer: Provides a detailed list of all MediaFile elements, including codec, bitrate, dimensions, and MIME type, allowing users to instantly verify delivery compatibility across various video players.
- Error Code Reference: Each detected VAST error is linked to its full IAB error code description and common fix recommendations, significantly speeding up troubleshooting.
- Zero Configuration & 100% Free & Private: No account, API key, or browser extension is required. The tool is completely free to use, and all VAST tags are processed privately without being stored or logged.
How to Use:
- Paste Your VAST URL or XML: Enter a VAST tag URL from your ad server (e.g., DFP, GAM, Freewheel) or paste raw VAST XML directly into the input field.
- Click Validate: The tester fetches and parses the tag, follows wrapper chains, and performs all spec checks in real-time.
- Inspect Results & Fix Issues: Review the detailed results, including detected errors, warnings, tracking pixels, and media files. Use the provided error descriptions and IAB spec references to quickly resolve any problems.
This VAST Tag Tester is an indispensable resource for programmatic advertising engineers, ad ops, and publisher monetization teams, offering unparalleled insight into video ad performance and helping to protect revenue by catching critical issues before they affect viewers.
