TTML to STL Subtitle Converter
Convert TTML cue timing and text into Spruce-style text STL entries.
Drag & drop your TTML file here
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Supports .ttml, .itt, .xml files up to 50 MB
Free Online TTML to STL Converter
This converter reads <p> cues from a TTML document and writes text-based Spruce STL output. Timing is quantized to a 29.97 fps frame grid, line breaks become vertical-bar separators, and common inline TTML tags are removed. Each output cue contains a start time, end time, and text.
TTML to STL Code Syntax & Structure Inspection
Side-by-side code inspection illustrating header definitions, timestamp syntax, and cue payload formatting
TTML vs STL Technical Specifications
TTML
TTML (Timed Text Markup Language) is an XML subtitle format. This converter looks for <p> elements with begin and end, or begin and dur, timing attributes, and accepts second-based or clock-valued timing. Cues without a begin attribute are skipped.
STL
This output is text-based Spruce STL, not binary EBU STL. The file includes generator comments followed by start time, end time, and text entries. Timing uses SMPTE-style HH:MM:SS:FF values at 29.97 fps, and display line breaks are represented with vertical bars.
Format Differences
Conversion Troubleshooting & Gotchas
Practical solutions for player compatibility, character encoding, and timing synchronization
Subtitle timing drifts or appears out of sync on media players
Video files frequently differ in framerate (e.g., 23.976 fps vs 25 fps). If the timing drifts steadily, use our Subtitle Sync tool to adjust the global offset or framerate stretch.
Characters appear as garbled symbols or question marks (Mojibake)
Legacy files saved in Windows-1252, Shift-JIS, or GBK may render incorrectly. Our exporter standardizes output to clean UTF-8. Use our Subtitle Encoding Converter if the source file is corrupted.
Overlapping captions when multiple speakers talk simultaneously
Different formats handle overlapping dialogue differently. If your target player cannot render stacked cues cleanly, open the file in our Subtitle Editor to adjust individual cue timings.
Video editing software (Premiere, DaVinci, Final Cut) rejects the file
Professional NLE software enforces strict syntax rules. Our converter eliminates malformed line breaks and non-standard tags, producing clean, standardized files.
Features
Why Convert?
Common Use Cases
Text STL Preparation
Create text-based Spruce-style STL entries from supported TTML cues.
Line-Break Conversion
Convert TTML line breaks into STL vertical-bar separators.
Timing Conversion
Move begin and end values into frame-grid SMPTE-style timecodes.
Related Formats
How It Works
- 1
Select or drop a TTML file.
- 2
The parser extracts <p> text and timing attributes.
- 3
Common inline tags are removed and line breaks are retained.
- 4
Timing is converted to SMPTE-style frame timecodes.
- 5
Each cue is written as start, end, and pipe-separated text.
More Subtitle Tools
Frequently Asked Questions
No. The output is text-based Spruce STL with start, end, and text entries. Binary EBU STL is not generated.
Times are quantized to a 29.97 fps SMPTE-style frame grid. TTML millisecond precision may be adjusted to the nearest supported frame representation.
Yes. There is no registration or watermark, and conversion happens in your browser.
TTML line breaks are written as vertical-bar separators in the STL text field.
No. Common inline tags are removed and no TTML styling or metadata is mapped.
No. Processing stays in your browser and the subtitle file is not uploaded.
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