Subtitle Converter
Convert subtitles between SRT, WebVTT and ASS, and shift their timing to fix out-of-sync captions.
Free · No upload · 100% on your device
Subtitle Converter
Choose subtitle files, or drop them here.
SRT, WebVTT, ASS · No size or length limit. Nothing is uploaded.
100% on your device
How to use Subtitle Converter
- Choose your subtitle files, or drop them on the page.
- Pick the settings in the side panel.
- Select “Convert subtitles”. The first use downloads the video engine once.
- Download the result. Your original file is left unchanged.
Private by design. Your files are processed in this browser tab and are never uploaded to KittySuite.
About Subtitle Converter
Use a positive shift when the captions appear too early and a negative one when they appear too late, in seconds (0.5 is half a second). Styling that one format does not support, such as ASS colours in SRT, is dropped.
Processing happens in this tab with FFmpeg compiled to WebAssembly; your files are never uploaded. The first video or audio tool you use downloads the 10 MB engine once and keeps it cached for next time. Long or high-resolution videos take longer than on a desktop editor, especially on phones, where files are processed one at a time to stay within memory. Keep the tab open until the download appears.
Subtitle Converter: frequently asked questions
How do I convert SRT to VTT?
Choose the subtitle file, pick WebVTT and convert. You can also convert to SRT or ASS.
How do I fix subtitles that are out of sync?
Enter a shift in seconds: positive when captions appear too early, negative when they appear too late. 0.5 is half a second.
Is styling kept?
Only what the target format supports. ASS colours and positions, for example, are dropped when saving as SRT.
Can I convert several files?
Yes. Add a batch; each file is converted with the same settings.