KiiMix Subtitle format converter
Convert SRT, VTT, ASS or SSA subtitles to the format your player or editor requires. The result keeps subtitle text and timing; complex styles and positioning are removed.
How to use
- 1Add SRT, VTT, ASS or SSA files to the workspace; each batch accepts up to 10 files.
- 2Choose SRT, VTT or ASS output. If the preview looks garbled, select the file and change its input encoding.
- 3Click Process all, check the result, then download it from the file list or preview with the original base name and a new extension.
Specifications and output
This tool changes the subtitle file format without changing the language or deliberately shifting the timing. It is suitable when you already have a subtitle file and need a different format for another application. Keep the source file if its appearance matters.
| Input formats | SRT, VTT, ASS and SSA |
|---|---|
| Output formats | SRT, VTT or ASS, encoded as UTF-8 |
| File and batch limits | 2 MB per file; up to 10 files per batch |
| Text and timing | Basic text and timing are kept; ASS output has 10 ms precision |
| Styles and layout | Inline formatting and positioning are removed; ASS uses a default style |
Choose the format required by your player or editor
Check the receiving application’s subtitle requirements before converting. A different extension alone does not change a file’s format: the converter reads its timed entries and writes a new SRT, VTT or ASS file. The original file is left unchanged.
Converting ASS to SRT or VTT removes fonts, positioning, layers and animation. ASS-to-ASS conversion also rebuilds the file with a default style, so it is not a way to preserve an existing ASS design.
Check the input encoding when characters look wrong
A subtitle’s format and character encoding are separate. An SRT file can contain UTF-8, GBK or another encoding, and an incorrect choice can produce readable timestamps but garbled dialogue. Select that file and try GB18030 for GBK text, Big5 for traditional Chinese, or UTF-8/UTF-16; changing the output format alone will not fix the input decoding.
Common questions
Will conversion change when subtitles appear?
The converter keeps the parsed start and end times and does not synchronize subtitles to a video. SRT and VTT output keep millisecond timing, while ASS output is written at 10 ms precision. If dialogue is already early or late, changing the file format will not correct it.
Can I convert several files at once?
Yes. Add up to 10 files; each file must be no larger than 2 MB. The output format applies to the batch, while input encoding can be changed separately for each file. A failed file does not prevent the others from producing results.
Will conversion overwrite or upload my original?
No. Decoding and conversion run in your browser, and the download is a separate file with the original base name and a new extension. The page does not modify the source file or save it to an account. Download your results before closing or reloading the page.
Subtitle formats and encoding guide →