Convert TTML to DFXP Online Free
Convert W3C TTML subtitle files to DFXP format for compatibility with legacy broadcast delivery systems and professional subtitle tools. ChangeThisFile handles the conversion server-side.
By ChangeThisFile Team · Last updated: March 2026
ChangeThisFile converts TTML to DFXP on a secure server. Upload your TTML subtitle file and it is re-encoded as DFXP for legacy broadcast systems and professional subtitle tools. Files are auto-deleted after conversion. Free with no signup required.
Convert TTML to DFXP
Drop your TTML file here to convert it instantly
Drag & drop your .ttml file here, or click to browse
Convert to DFXP instantly
TTML vs DFXP: Format Comparison
Key differences between the two formats
| Feature | TTML | DFXP |
|---|---|---|
| Standard body | W3C Timed Text Working Group | Industry EBU/SMPTE distribution profile |
| Version support | TTML 1.0, TTML 2.0 | TTML 1.0 subset |
| Namespace | W3C ttml namespace | Older TTAF exchange namespace (varies) |
| Modern tool support | High — current broadcast systems | Moderate — legacy systems |
| Feature set | Full W3C spec including TTML 2 | Distribution-focused subset |
| Validation | W3C TTML validator | DFXP/TTAF schema |
| Best for | Current streaming delivery | Legacy broadcast tool compatibility |
When to Convert
Common scenarios where this conversion is useful
Submitting to legacy broadcast systems requiring DFXP
Some older broadcast delivery systems and subtitle management tools still require DFXP with legacy namespace declarations. Converting modern TTML output to DFXP ensures compatibility with these systems.
Round-tripping between subtitle vendors
One subtitle vendor may deliver TTML while another tool in the workflow requires DFXP. This converter normalizes the format for interoperability between tools in a mixed professional environment.
Archiving current TTML in a legacy-compatible format
Organizations maintaining long-term subtitle archives may need DFXP copies for compatibility with older retrieval and playback systems alongside modern TTML masters.
How to Convert TTML to DFXP
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1
Upload your TTML file
Drag and drop your TTML subtitle file onto the converter, or click browse to select it. The file is transferred over an encrypted connection.
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2
Server-side conversion
The server parses the TTML XML, extracts cue timing and text, and re-encodes as DFXP with appropriate namespace declarations for professional delivery system compatibility.
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3
Download the DFXP
Save your converted DFXP file. The server copy is automatically deleted after processing.
Frequently Asked Questions
TTML is the W3C core specification; DFXP is an older distribution profile of TTML defined by the SMPTE/EBU for broadcast interchange. Both are XML formats; DFXP uses an older namespace convention and is limited to TTML 1.0 features.
Timing and text content are fully preserved. TTML 2.0-specific features not supported in DFXP are dropped. The conversion is a namespace and schema normalization.
Some legacy EZTitles, Cavena, and Fab Subtitler versions, as well as certain broadcast content management systems, require DFXP with older namespace declarations rather than modern W3C TTML.
Yes. Files are transferred over HTTPS and automatically deleted from the server after the DFXP is ready for download.
The output DFXP uses standard W3C TTML namespace with DFXP-compatible structure. If your legacy tool requires the older TTAF namespace specifically, you may need to manually update the namespace declarations.
TTML files are XML text and typically compact. The 50 MB server limit is not a concern for subtitle files.
Yes. ChangeThisFile supports DFXP to TTML conversion for round-tripping between formats.
DFXP uses HH:MM:SS.mmm for begin and end attributes on each p element, same as TTML.
IMSC-1 is a Netflix-specific TTML profile. The converter extracts cues from any valid TTML XML. IMSC-1 specific metadata in the tt element head is preserved in the DFXP output where compatible.
Yes. The output is well-formed XML that passes any XML parser. For DFXP-specific validation, use the W3C TTML validator or a DFXP schema validator.
Related Conversions
Need to convert programmatically?
Use the ChangeThisFile API to convert TTML to DFXP in your app. No rate limits, up to 500MB files, simple REST endpoint.
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