About SubTrans
SubTrans is a free online tool for fast and easy subtitle file conversion. It supports various subtitle formats including SRT, SMI, VTT, ASS/SSA, SUB (MicroDVD), and SUP (Blu-ray PGS), and can be used directly in your web browser without any installation.
- Format Conversion — Convert between SRT, SMI, VTT, ASS, and SUB
- Encoding Conversion — Auto-detect and convert UTF-8, EUC-KR
- Sync Adjustment — Adjust subtitle timing in milliseconds
- Search/Replace — Plain text and regex support
- Time Range Extract — Extract specific time segments
- Multi-file Merge — Combine multiple subtitle files into one
- Translation — Translate subtitles using Google Translate API
- Blu-ray PGS OCR — Extract text from SUP image subtitles
Basic conversion tasks (format conversion, encoding, sync adjustment, search/replace) are processed entirely in your browser. Files are never sent to any server, ensuring complete privacy. Only SUP OCR and translation features use server communication, and all data is immediately deleted after processing.
SubTrans is an open-source project. You can find the source code on GitHub.