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Caption Converter

Caption formats should not cost you an afternoon. Convert between SRT, WebVTT and TTML, pull a plain transcript out, and find the overlaps and unreadable cues before your LMS does.

Free · No account · Your files never upload

Drop a caption file, or paste it below

Files are read in your browser. Nothing is uploaded.

What this does

Reads SRT, WebVTT and TTML, works out which one you gave it, and writes any of them back out, or strips the timings entirely for a plain transcript. It also checks the file while it is in there: overlapping cues, cues out of order, cues with no duration, and text moving too fast to read.

When you’d reach for it

Your vendor delivered SRT and the player wants VTT. An LMS rejects a file with no useful error message. You need a readable transcript for the accessibility pack, or to hand narration text to a translator. Or a caption file works in one player and silently fails in another, and you need to know what is actually wrong with it.

About the reading-speed check

Captions are flagged above twenty-one characters per second, which is a common upper limit for adult audiences; broadcast and accessibility guidance generally sits between fifteen and twenty-one. Going over does not break anything technically. It just means some viewers cannot finish the line before it disappears, which is the failure nobody reports and everybody experiences.

Your file stays with you

Everything happens in your browser. The file is read from your disk, converted in the page, and offered back as a download. Nothing is sent anywhere, which matters when the captions belong to a client’s unreleased course.

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