Add your SRT file
Drop one or more .srt 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.
SRT to TTML
Converting a .srt file to .ttml 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 SRT 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 SubRip subtitles to Timed Text Markup Language
Converting a .srt file to .ttml extracts the document's content from its office package into a portable form. A .srt file is a SubRip subtitle document: numbered cues with start and end timestamps and plain caption text. It is the most common caption sidecar for video players, editors, and streaming toolchains that need a simple, widely understood text format.
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. For this route the practical draw is a real published standard with formal profiles rather than a de facto convention and expresses styling, layout, and regions that plain caption formats cannot — balanced against far more verbose than SubRip or WebVTT for the same cues, which is worth knowing before you commit a large batch.
Why convert SRT to TTML?
The practical trigger for this conversion is usually a mismatch: with .srt, no standard support for advanced styling, voices, or regions. Switching to .ttml buys you a real published standard with formal profiles rather than a de facto convention, which is why it is the better fit for delivering captions to broadcast and streaming platforms that mandate a TTML profile. Because the conversion runs locally, trying it costs nothing but a few seconds of compute on your own machine.
SRT vs TTML at a glance
| Aspect | SubRip subtitles (.srt) | Timed Text Markup Language (.ttml) |
|---|---|---|
| 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 | cues are blocks of an index, a timecode arrow line (HH:MM:SS,mmm --> HH:MM:SS,mmm), one or more text lines, and a blank separator | the root <tt> element declares the TTML namespace and optional ttp: parameters such as frameRate, tickRate, and timeBase |
| Strongest at | delivering captions alongside MP4 or MKV downloads | delivering captions to broadcast and streaming platforms that mandate a TTML profile |
| Weak spot | no standard support for advanced styling, voices, or regions | far more verbose than SubRip or WebVTT for the same cues |
Pick TTML as the output
Select .ttml in the output menu next to each file. The menu only offers targets this engine can genuinely produce, so if TTML 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 TTML file. Outputs keep the original filename with the .ttml extension.
SRT to TTML questions, answered
Will converting SRT to TTML lose quality?
There is no visual quality to lose — srt is text-oriented and ttml 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 SRT files here?
Yes — the .srt 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 TTML file work?
Broadcast and streaming toolchains — including the DFXP, SMPTE-TT, EBU-TT, and IMSC profiles — read and write TTML, and caption editors such as Subtitle Edit export it. Browsers do not. Novus Convert parses TTML locally with document types and external entities refused outright, resolves all five time-expression shapes, and converts to any of the twelve timed-text targets.
Will the TTML file be bigger or smaller than my SRT?
It depends on the content: the root <tt> element declares the TTML namespace and optional ttp: parameters such as frameRate, tickRate, and timeBase. Convert one representative file first and compare before batch-processing a large set.
Can I convert TTML back to SRT?
Yes — the reverse route exists as a separate tool. Bear in mind that round-tripping .srt → .ttml → .srt is not a perfect undo when any lossy step is involved; keep your original if fidelity matters.