Ad Me In
Suggest a Feature

VAST Tag Tester & Player – Validate and Preview VAST Ads

Validate VAST ad tags and preview video ads in real time.
Our free VAST tag tester and player helps you debug errors before launching campaigns.

Enter Your VAST Tag URL for Testing

How to test a VAST URL

VAST Tag Examples

AdMeIn Icon ExampleVAST LinearAdMeIn VPAID ExampleVPAID InteractiveAdMeIn Single Wrapper ExampleVAST WrapperAdMeIn Multi Ad ExampleVMAP Multi-AdAdMeIn Companion Ads ExampleVAST CompanionGoogle Multi Ad ExampleGoogle IMAGoogle SIMID ExampleSIMID InteractiveAdform VAST SampleProduction ExampleInnovid ExampleThird-Party Server

How Our Online VAST Tester Works

  • Paste your VAST tag URL into the input field.
  • Click the "Validate" button to start the validation process.
  • Review the validation results and fix any issues using the provided feedback.

What is a VAST Tester?

A VAST tester is a tool that loads your VAST XML ad tag and simulates how a video player would interpret it. Instead of guessing whether your tags will deliver correctly, you can test them online and spot issues before launch.

VAST Video Ad Preview and Inspector

How the Video Preview Works

VAST Tag Preview & Validation

Once you paste your VAST tag URL and click Validate, your VAST tag preview will appear here. Our VAST tester online instantly loads your ad response, showing a live video ad playback, media file details, and tracking events.

Video ad previews are powered by the Google IMA SDK.

Our tester helps you:

  • Debug and troubleshoot VAST errors
  • Preview video ads in real-time
  • Inspect media assets and tracking pixels
  • Verify compliance with VAST standards
  • How to fix common VAST errors detected during validation

By running your tags through the preview, you can be confident your video ads will deliver correctly before launching campaigns.

VAST Validation Results

What We Test For

When you run a test in our VAST Tag Tester, we check your VAST or VMAP tag for the following common issues and best practices

Explore common VAST errors and troubleshooting tips.

VAST Version

pending

Checks if the VAST version is supported and valid.

We currently support all versions of VAST: 2.0, 3.0, 4.0, 4.1, 4.2

Learn about VAST versions

Media Files

pending

Ensures media files are present and properly formatted.

We support various media file types including MP4, WebM, and Ogg.

Learn about media file requirements

Duration

pending

Validates that the ad duration is specified and reasonable.

We recommend a duration of 15-30 seconds for most ads.

Learn about ad duration best practices

Tracking Events

pending

Checks for required tracking events and their correctness.

We support various tracking events including start, firstQuartile, midpoint, and complete.

Learn about tracking events

Click Tracking

pending

Verifies click tracking URLs are present.

Click tracking is essential for measuring ad engagement.

Impression Tracking

pending

Ensures impression tracking is implemented.

Impression tracking helps monitor ad views and performance.

Companion Ads

pending

Checks for valid companion ads if present.

Companion ads enhance user engagement alongside video ads.

Ad System

pending

Validates the AdSystem element.

AdSystem identifies the ad server or system that provided the ad.

API Framework

pending

Checks for correct API framework usage.

Common API frameworks include VPAID and SIMID.

Ad Sequence

pending

Validates ad pod sequence numbers (for sequential ads).

Ensures ad sequence numbers are unique and properly ordered.

Sequence Timing

pending

Checks total duration and timing of ad pods.

Ensures total ad pod duration is within acceptable limits.

VMAP Version

pending

Checks VMAP version (for VMAP tags).

We currently support VMAP 1.0.

Ad Breaks

pending

Validates ad breaks in VMAP.

Ensures ad breaks are properly defined and formatted.

Ad Break Timing

pending

Checks timing of ad breaks in VMAP.

Ad breaks should be scheduled at appropriate intervals.

VAST References

pending

Ensures VMAP ad breaks reference valid VAST tags.

We currently support VAST 2.0, 3.0, and 4.0+

Results example

After you validate your VAST tag, you'll see a detailed breakdown of each section of your VAST XML. The results show which parts passed, which failed, and how to fix any issues found.

Passed example:
- AdSystem, AdTitle, Impression
Failed example:
- MediaFile (missing or invalid URL)
Warning or Optional example:
- Companion Ads (optional)
Tip: Click on each result for more details and suggestions on how to fix any issues that may have been detected.
Visit our help center for more information:
Help Center docs on VAST Tag Validation Results

Always review your VAST tags in multiple VAST testers to ensure compatibility.

Helpful VAST guides.

Try our new VAST tag generator playground to generate and test VAST tags examples.

Get help on generating VAST tags
What is VAST & How to Test VAST Tags
VAST Testing

What is VAST & How to Test VAST Tags

Learn about VAST, how to test VAST tags, and best practices for video ad creatives. Explore our guides to ensure your video ads are compliant and error-free.

Ad Me In
Read guide

Frequently Asked Questions

What is a VAST tester?

A VAST tester is a tool that lets you simulate how a video player would process your VAST XML ad tag, helping you validate creatives, tracking, and delivery.

How can I test interactive video ads?

You can test interactive video ads using our video ad tester, which simulates the ad playback environment to ensure your interactive video creatives function correctly. Interactive video ads are often VPAID, SIMID and SHARC formats.

What is video ad pod?

A video ad pod is a group of video ads or a collection of ads that are played sequentially within a single ad break. This allows for multiple ads to be shown to the viewer in a single viewing session. Pods are generally scheduled to play at the beginning (pre-roll), in the middle (mid-roll), or at the end (post-roll) of the content.

How can I test a multi-VAST tag or VMAP tags?

You can test a multi-VAST tag or VMAP tags by using our VAST tester, which supports both formats and provides detailed validation results.

How do I test a VAST tag online?

Simply paste your VAST tag URL into our VAST tester online, and it will load the ad response, show the video playback, and report any issues.

What errors can a VAST tester detect?

Our tester checks for XML validation issues, missing creatives, wrapper problems, tracking errors, and more.

Is this VAST tester free?

Yes, our VAST tester is completely free to use.