SyncMySubsConvert EBU STL to SRT
Decode an EBU STL .stl file (EBU Tech 3264) into a readable, editable SRT. It reads the binary GSI header and each TTI block, pulling out the subtitle text and its in/out timecodes. Drop your STL below; it decodes in your browser, nothing is uploaded.
New to these formats? Broadcast caption formats explained →
Reads a standard EBU STL file's GSI header and TTI blocks (25 or 30 fps, Latin/ISO 6937 text). It decodes the subtitle text and in/out timecodes; teletext colours, boxing and exact positioning aren't carried into SRT. EBU STL is binary, so it must be dropped as a file, not pasted. (Some tools reuse .stl for the unrelated Spruce text format, which this doesn't read.)
Reading an EBU STL file
EBU STL (EBU Tech 3264) is a binary format, so you can't just open it in a text editor. It begins with a 1024-byte General Subtitle Information (GSI) block — frame rate, character table, subtitle counts and timecodes — followed by a 128-byte Text and Timing Information (TTI) block for each subtitle. This tool parses those blocks and reconstructs an ordinary SRT you can read and edit.
It reads the frame rate from the GSI header (25 or 30 fps) so the in and out timecodes convert correctly, decodes the ISO 6937 Latin text including its combining-diacritic accents, and joins multi-row subtitles with a line break. Comment blocks are skipped and multi-block (extended) subtitles are stitched back together.
Styling that STL can carry — teletext colours, boxing, exact positioning — has no standard SRT equivalent, so the tool keeps the text and timing and notes what it dropped. Need to write STL instead? SRT to EBU STL.
FAQ
Is this for EBU STL or the Spruce text .stl?
EBU STL (EBU Tech 3264) — the binary broadcast format with a GSI header and TTI blocks. The Spruce Subtitle File shares the .stl extension but is a different, text-based format; if the file isn't EBU STL the tool says so rather than producing garbage.
Why can't I paste the file?
EBU STL is binary, not text, so pasting it wouldn't survive. Drop the .stl file (or click to choose it) and the tool reads the raw bytes directly.
What gets converted?
The subtitle text and each subtitle's in and out timecodes, at the frame rate declared in the header. Teletext colours, boxing and precise positioning don't have an SRT equivalent and are left out — that's noted after each conversion.
Are accented characters handled?
Yes. The Latin ISO 6937 character table, including its combining-diacritic accents, is decoded, so European-language text and names come through. Anything outside the supported subset is shown as "?" and flagged.
Is my file uploaded anywhere?
No. The STL is parsed in your browser. Your file never leaves your device and no server is involved.