SRT to ASS converter
Convert SRT subtitles to ASS. Drop in a file or paste the text — the conversion runs inside your browser and nothing is sent to a server.
SRT vs ASS
The most widely supported subtitle format: VLC, Premiere Pro, DaVinci Resolve, PowerDirector and virtually every player read it. Each cue is a number, a `HH:MM:SS,mmm --> HH:MM:SS,mmm` line, the text and a blank line. Milliseconds are separated with a comma. ASS, by contrast: The staple of anime fansubs and karaoke typesetting, edited in Aegisub and burned in with mpv, MPC-HC or ffmpeg. It has [Script Info], [V4+ Styles] and [Events] sections. Dialogue lines carry override tags such as {\an8} and use \N for line breaks, with centisecond precision.
How to use it
Choose a subtitle file or paste the text, then press Convert. Files saved as Shift_JIS or UTF-16 are detected and decoded automatically, and the output is always UTF-8. You can pick CRLF or LF line endings so the file opens cleanly in Windows editors too.
What changes in the conversion
A [Script Info] block and a Default style (Arial 48px, 1920x1080 play resolution) are generated for you, and line breaks become \N. Open the result in Aegisub to refine the styling.
Frequently asked questions
Are my subtitle files uploaded anywhere?
No. The conversion runs as JavaScript inside your browser, so the file contents never cross the network. That matters for subtitles, which are effectively the script of a video that may not be public yet. The page also keeps working offline once loaded.
Is it free? Do I need an account?
It is completely free with no sign-up and nothing to install. There are no conversion limits and no file-size cap beyond your browser memory.
Can it read a file that shows up as gibberish?
Yes. Shift_JIS, EUC-JP, UTF-16 and UTF-8 with a BOM are detected automatically. If you already pasted garbled text, load the original file in the Fix subtitle encoding tool instead.
Will the timings drift?
No. Times are held as whole milliseconds internally and rendered in the ASS notation on output. ASS and LRC store centiseconds, so the final millisecond digit is truncated by the format itself.