Tool
VAST Inspector
VAST Inspector
Test and debug VAST tags with full XML inspection, playback simulation, and real-time event tracking—all in one tool. Built for QA teams and video operations specialists, this tool uses the Google IMA SDK to simulate real-world playback and surface issues in tag structure or delivery. Paste your VAST tag to view formatted XML, preview creative playback, and monitor SDK events like load, start, and complete in real time. It’s ideal for troubleshooting wrappers, verifying third-party tags, or confirming tracking pixels. Everything runs client-side for speed and privacy during development and testing.
Load a video tag and preview its structure and playback signals in one place.
How it works
The VAST Inspector allows QA teams to simulate video tag playback using the Google IMA SDK and see errors, tracking events, and inline XML content instantly.
Use it to analyze VAST tags or URLs, validate versions, and inspect wrapper chains before ad delivery.
What you can do with it
- Saves time debugging broken tags and playback issues.
- Gives visual insight into VAST macros and third-party calls.
- Emulates playback behavior in a clean testing environment.
Common tasks
- Confirm a tag resolves and plays as expected.
- See wrapper depth and tracking events quickly.
- Share a clean breakdown with teammates.
Quick steps
- Paste a VAST URL or raw XML into the editor.
- Click 'Inspect' to launch a simulated player with event tracking.
- Review impressions, errors, quartiles, and XML structure side-by-side.
Before you start
- Paste a VAST URL or XML.
- Use an example if you want to test the UI.
What you get
- Parsed XML with key fields summarized.
- Event log showing playback and errors.
Common pitfalls
- Private URLs may fail if they require auth.
- Some tags block automated requests.
Tips for best results
- Include the full URL (with https://) for best results.
- If a fetch fails, confirm the endpoint is publicly reachable.
- Some hosts block automated requests; try a different URL if needed.
Accuracy & limitations
- Outputs are deterministic and based only on the input you provide.
- When official specs exist, the tool favors strict parsing over guesses.
- URL-based tools can vary by region, cache, or upstream availability.
- Always validate critical outputs in your production systems before launch.
Trust & quality
- Validates against published IAB specs when available.
- Surfaces wrapper depth, errors, and playback signals clearly.
Who it is for
- QA and support teams validating outputs before launch.
- Analysts and operators who need fast clarity on raw data.
- Engineers and technical writers documenting system behavior.
When to use this tool
- You need a quick answer without scripting or a full IDE.
- You want a repeatable, shareable output for teammates.
- You are troubleshooting inconsistent or malformed input.
Quick checklist
- Input is complete and copied in full.
- Output matches expectations and no errors are shown.
- Share or export the result if you need to keep a record.
Frequently asked questions
Is it free to use?
Yes. Core tools are free and accessible without signup.
Does it upload my data?
This tool makes server-side fetches to the URLs you provide so results can be rendered. We do not store the fetched content beyond the request.
What if I spot a bug?
Please reach out via the Contact page with a reproduction example.
Does it make network requests?
Yes, only when you provide a VAST URL for analysis.
Which VAST versions are supported?
VAST 2.x through 4.x with automatic detection.
Why might schema validation fail?
Macros or strict XSD constraints can fail in some environments.
Helpful links
Standards & references
Official specs that inform how this tool interprets data.