Add your TTML file
Drop one or more .ttml files onto the converter above, or browse for them. They load into browser memory only — nothing is uploaded, so there is no size-based pricing and no server queue.
TTML to VTT
Converting a .ttml file to .vtt extracts the document's content from its office package into a portable form. Free, private, and validated — the file never leaves your browser.
Private for supported formats — processed in your browser
Runs on your deviceConvert supported files
Drop TTML files here
Batch files can each use a different output. Nothing uploads for local conversions.
Working inputs include camera RAW, browser-local audio/video, PDF, CBZ/CBR comics, office documents, ebooks, markup, 3D models, structured text, images, and archives.About converting Timed Text Markup Language to WebVTT subtitles
Converting a .ttml file to .vtt extracts the document's content from its office package into a portable form. A .ttml file is a Timed Text Markup Language document: an XML vocabulary in which each <p> element carries begin and end (or dur) attributes plus the caption text. It is the W3C standard that broadcast and streaming systems use as their interchange format for captions and subtitles.
A .vtt file is a WebVTT caption document: a WEBVTT header followed by timed cues for HTML5 video and audio. It is the web-native caption format browsers expect for the track element. For this route the practical draw is first-class support in modern browsers and richer cue settings than SubRip — balanced against some legacy desktop players prefer .srt and mishandle WebVTT settings, which is worth knowing before you commit a large batch.
Why convert TTML to VTT?
The practical trigger for this conversion is usually a mismatch: with .ttml, far more verbose than SubRip or WebVTT for the same cues. Switching to .vtt buys you first-class support in modern browsers, which is why it is the better fit for captioning HTML5 video with the track element. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
TTML vs VTT at a glance
| Aspect | Timed Text Markup Language (.ttml) | WebVTT subtitles (.vtt) |
|---|---|---|
| Format type | Text-based — characters and structure, so there is no visual quality loss | Text-based — characters and structure, so there is no visual quality loss |
| How it stores data | the root <tt> element declares the TTML namespace and optional ttp: parameters such as frameRate, tickRate, and timeBase | files begin with WEBVTT and optional metadata headers before the first blank line |
| Strongest at | delivering captions to broadcast and streaming platforms that mandate a TTML profile | captioning HTML5 video with the track element |
| Weak spot | far more verbose than SubRip or WebVTT for the same cues | some legacy desktop players prefer .srt and mishandle WebVTT settings |
Pick VTT as the output
Select .vtt in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if VTT is selectable, the route is real and validated.
Convert on your device
Press Convert. The package is unzipped in memory and its XML content parsed locally; nothing is uploaded.
Verify and download
Each result is signature-checked before the download unlocks, so a failed encode can never masquerade as a valid VTT file. Outputs keep the original filename with the .vtt extension.
TTML to VTT questions, answered
Will converting TTML to VTT lose quality?
There is no visual quality to lose — ttml is text-oriented and vtt is text-oriented, so the question is structural fidelity. Text, ordering, and basic structure are preserved; complex layout, embedded objects, and styling beyond the target's model are simplified.
Is it private to convert TTML files here?
Yes — the .ttml file is processed inside your browser tab and never uploaded. The package is unzipped in memory and its XML content parsed locally; nothing is uploaded. Close the tab and the file is gone from memory.
Where will the VTT file work?
Chrome, Firefox, Safari, and Edge render .vtt through HTML track elements. Professional editors and many downloadable players also import it, though SubRip remains more common in older desktop workflows.
Will the VTT file be bigger or smaller than my TTML?
It depends on the content: files begin with WEBVTT and optional metadata headers before the first blank line. Convert one representative file first and compare before batch-processing a large set.
What happens to the metadata in my TTML file?
In .ttml, styling, layout, and region definitions are read past rather than applied: timing and text convert, presentation does not, and no external resource is ever fetched. Re-encoding through the browser pipeline does not carry embedded metadata into the output, which doubles as a privacy scrub — check the exported file if you specifically need tags preserved.
Can I convert VTT back to TTML?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .ttml → .vtt → .ttml is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.