VAST Tag Validator
Use this tool to validate your VAST tags by entering a VAST tag URL or VAST XML content. The validator will analyze the structure of your VAST XML, check for common errors, and provide insights to help you debug any issues.
Other Ad Validators
VAST Preview Overview
Render your video ad tags in a safe, production-like player while AdMeIn validates every creative signal.
Go beyond basic Ad previews
Create a free account to access advanced test features and save your test history
What the preview reveals
The preview panel mirrors a production video player and layers diagnostics directly on top of the creative.
- Ad duration, bitrate, codec, and aspect ratio pulled from the media file itself.
- Quartile markers that light up as each tracking URL fires, so you instantly see what failed.
- Inline vs wrapper media prioritization with a callout whenever a wrapper blocks playback.
- Companion ad previews for display units that ship alongside the video execution.
Inside the registered workflow
Create a free account to unlock saved sessions, shared links, and deeper validation history.
- Load your tagPaste XML, drop in a URL, or pull from saved test profiles. The preview instantly normalizes namespaces and reveals wrapper hops.
- Inspect playbackUse the built-in controls to scrub, mute, view quartile callouts, and inspect companion creatives side-by-side.
- Fix with contextEach validator message links back to the preview timeline, so creative, dev, and ad ops teams can troubleshoot together.
Power user extras
Logged-in teams can pin multiple preview panels side-by-side, export validator summaries, and invite teammates to comment right inside the playback timeline. These collaboration upgrades make it easy to document compliance evidence for clients or publishers.
Built for fast QA cycles
The preview refreshes in milliseconds whenever you adjust XML, swap media files, or change player presets. Pair it with automated alerts to keep campaign launches on schedule without sacrificing accuracy.
Key Features
- Real-time player preview for VAST 2.x through 4.2 with inline and wrapper support
- Instant error overlays that map validation findings to the exact moment in playback
- One-click fetch for remote tags, XML paste mode, and VMAP playlist handling
- Secure media proxying so third-party assets stay private while you test
- Quick toggles for quartile events, companion ads, and tracking pixels
- Device-ready sizing presets to mimic OLV, OTT, CTV, and desktop players
Go beyond basic Ad previews and Turn Ad testing into real insights
Creating an account allows you to unlock additional features such as saving your test history, accessing advanced validation reports, and receiving personalized support. Enhance your ad testing experience and streamline your workflow by signing up today!
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- Save and access your test history anytime
- Get detailed validation reports
- Access advanced testing features
- Access to premium validation features
- Priority features and updates
- Clean dashboard without ads and clutter