HLS / SSAI Inspector
Inspect a publisher HLS stream for SSAI ad breaks. Paste an m3u8 URL to see CUE-OUT/IN, DATERANGE and SCTE-35 markers, ABR ladders, and play the stream with breaks marked on the timeline.
Some CDNs block hotlinking. Set this to the publisher page/site URL if analyze returns HTTP 403.
Ready — paste a publisher m3u8 URL.
Stream summary
Stream info
Inferred from the playlist and URL. HLS rarely includes channel/EPG titles — that usually lives on the publisher site.
Subtitles
Download merges subtitle segments into one .vtt. Live streams export the current window only.
ABR variants
How it works
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1. Paste the publisher m3u8
Use the master or media playlist from the site / SSAI CDN (not a VAST creative URL).
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2. We fetch & parse
The server downloads the playlist (and top ABR variants), then extracts CUE-OUT/IN, DATERANGE, SCTE-35 and discontinuities.
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3. Play with markers
HLS.js plays the stream; ad breaks are drawn on the progress bar. Enable proxy if the CDN blocks browser CORS.
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4. Download subtitles
If the master lists WebVTT tracks (#EXT-X-MEDIA TYPE=SUBTITLES), download a merged .vtt file.
FAQ
What is SSAI?
Server-Side Ad Insertion mixes ads into the publisher video stream on the server. The player often sees a single HLS playlist; ad breaks may be signaled with CUE-OUT/IN, DATERANGE or SCTE-35 tags.
Why are there no ad markers?
Some SSAI vendors splice ads without exposing HLS cue tags (“opaque” SSAI). Markers may also appear only on certain media playlists, or only in the live window you fetched.
Is this the same as the VAST Tester?
No. VAST Tester validates ad tags and creatives. This tool inspects the publisher HLS stream for SSAI break signals and playback.
Can I download subtitles?
Yes when the master playlist exposes WebVTT via #EXT-X-MEDIA TYPE=SUBTITLES. Closed captions embedded in video (CEA-608/708) are not exported as a separate file.