Can I test raw VAST XML without hosting it?

Yes. Switch to Paste XML — the document is handed to the SDK through AdsRequest.adsResponse. VMAP as a pasted string is not reliably supported by the SDK; test VMAP by URL instead.

What do the error codes mean?

Codes 100–901 come from the IAB VAST specification (for example 303 means no ad after the wrapper, i.e. no fill). Codes 1000+ are IMA-specific, such as 1009 empty response or 1012 network error. The Error tab explains each one with likely causes and fixes.

Why does the player start muted?

Browsers only allow autoplay with sound after a user gesture, and the SDK reports the muted state to the ad server via setAdWillPlayMuted. You can unmute in the control bar or in the settings; the tool also fills [VPMUTE] and vpmute= macros accordingly.

Do VPAID creatives work?

Yes when VPAID mode is ENABLED (secure iframe, the default) or INSECURE (friendly iframe, for debugging trusted creatives only). DISABLED skips VPAID media files, which is useful to confirm a tag has an MP4 fallback.

How is this different from Google's Video Suite Inspector?

It runs the same IMA SDK, but keeps the request settings, macro expansion, wrapper chain, error explanations, run history and exportable reports in one place, and hands the XML straight to the FizzKit VAST Inspector for structural checks.

VAST Ad Tester (IMA Player)

Paste a VAST/VMAP tag URL or raw VAST XML and run it through the Google IMA HTML5 SDK exactly as a production player would. The tool expands request macros, shows time-to-LOADED and time-to-STARTED, every ad getter (IDs, creative, media size and bitrate, skip offset, pod position, wrapper chain, Universal Ad IDs), quartile pixels as they fire, VMAP cue points, and a full event timeline in milliseconds. Fatal AdErrors and non-fatal LOG errors are explained with likely causes and fixes, and each run can be copied as a Markdown report or downloaded as JSON.

Runs in your browser, loads a third-party SDK

Open fullscreen to see the player and timeline side by side

loading SDK…

VAST / VMAP tag URL

Sample tags

Auto-fill macroscorrelator=→—

Final URL sent to the SDK

—

⌘ Enter runs · the SDK requests the tag from your browser

Player

640×360 · idle

Run a tag to start

Content plays muted; ads render in the overlay above it.

0:00 / 0:00content

Quartiles (from SDK events)

—

25%50%75%100%

Auto-scroll

Run a tag to see SDK events here, with milliseconds since the request.

Recent runs

No runs yet. The last 10 runs are kept in this browser.

The Google IMA HTML5 SDK is loaded from imasdk.googleapis.com and requests the tag directly from your browser — nothing is proxied through FizzKit, so what you see is what a real player sees (cookies excluded). Ad blockers usually break this tool. IMA SDK docs

VAST Inspector

Fetch or paste VAST 2/3/4 tags — follow wrapper chains, validate, ping pixels, and play media files.

VMAP Parser

Fetch or paste VMAP 1.0 manifests — timeline preview, resolve every AdTagURI to VAST, validate, and ping break trackers.

HLS m3u8 Parser

Fetch or paste HLS playlists — drill from master to variants, validate the ladder, HEAD-check segments, decode SCTE-35 cues.

OpenRTB Inspector

Validate & annotate OpenRTB 2.6 BidRequest and BidResponse JSON.

ads.txt / app-ads.txt Validator

Fetch any domain's ads.txt or app-ads.txt, validate it against the IAB 1.1 spec, follow SUBDOMAIN pointers, and cross-check every line against exchange sellers.json files.

How to use VAST Ad Tester (IMA Player)

1Pick a Google sample tag or paste your own VAST/VMAP tag URL (or switch to Paste XML and drop in a VAST document).
2Check the macro chips and final URL, then press Run or ⌘ Enter — the click doubles as the autoplay gesture.
3Watch the player, quartile bar and timeline; open the Ad tab for every SDK getter and the Wrappers tab for the redirect chain.
4If it fails, the Error tab shows the code, the SDK message and what usually causes it.
5Copy the Markdown report, download the JSON, or send the XML to the VAST Inspector.

About VAST Ad Tester (IMA Player)

VAST Ad Tester (IMA Player) is part of FizzKit — a collection of focused developer and ad-tech tools. This tool loads a third-party SDK in your browser; your input is sent only where that SDK needs it (for example, to the ad server you are testing).

Frequently asked questions

The IMA SDK loads from imasdk.googleapis.com and requests tags from pubads.g.doubleclick.net or your ad server directly in your browser. Ad blockers and privacy extensions block those hosts. Allow both hosts for fizzkit.net (or disable the blocker on this page) and press Retry.

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