Free Online Subtitle Converter
Convert subtitle files between SRT, VTT and ASS formats in milliseconds. Auto-detects the input format, preserves timestamps and Unicode — runs entirely in your browser, no upload, no signup.
Features
Every Common Subtitle Format
SRT, VTT and ASS — auto-detected on upload, freely converted between any pair. No manual parsing, no broken timestamps.
SRT (SubRip)
The desktop standard used by Premiere, DaVinci Resolve, VLC and most editing software.
VTT (WebVTT)
The web standard for HTML5 video — required by every modern browser-native player.
ASS (Advanced SubStation Alpha)
The styled-subtitle format used by anime fansubs, MKV releases and Aegisub workflows.
Accurate & Lossless
Millisecond-precise timestamp conversion and full Unicode support. Your subtitles come out exactly as they went in — only the wrapper changes.
Timestamp Precision Preserved
Comma vs dot vs hundredths — the converter handles every format's quirks without losing a single millisecond.
Full Unicode Support
Chinese, Japanese, Korean, Arabic, Thai, emoji — every character is preserved byte-for-byte.
Auto Format Detection
Drop any subtitle file and we detect SRT, VTT or ASS automatically — no need to label it.
100% Private & Free
Your subtitles never leave your device — everything runs as plain JavaScript inside the browser tab.
Zero Server Upload
Files are read, parsed, converted and written back entirely on your own machine.
Instant Download
Conversion completes in milliseconds — click and the new subtitle file is ready.
Works Everywhere
Any modern browser — desktop or mobile. Chrome, Firefox, Safari, Edge.
FAQ'S
Frequently Asked Questions
Ask us anything!
Convert Your Subtitles Now
Free, private and instant. No signup, no upload, no watermark — drop a subtitle file and download the converted version in seconds.