Subtitle Converter

Subtitle files come in many dialects: SRT from download sites, WebVTT for web players, ASS from fansub editors such as Aegisub, SMI (SAMI) files that Korean players have used for decades, SBV from YouTube Studio, frame-based MicroDVD .sub files, and LRC lyrics. This converter reads all of them, works out the format and the text encoding by itself, and writes the one your player, editor or upload form expects. Several files can be converted at once, and nothing leaves your browser.

How to use this tool

1. Choose one or more subtitle files, or paste the subtitles into the box.
2. Pick the format to convert to.
3. For MicroDVD .sub files, enter the video's frame rate; for Korean SMI files with two languages, pick the language class.
4. Copy the converted text, or download the files (several come as one ZIP).

Formula

Every format → list of cues (start, end, text) → the chosen format

Times are kept to the millisecond where the format allows it: ASS stores hundredths of a second, LRC hundredths, MicroDVD whole frames (time × frame rate, rounded). SAMI has no end times, so a cue lasts until the next sync; LRC lines last until the next line. Italic, bold and underline survive between SRT, WebVTT, ASS and SAMI; positions survive only as "top of the screen" ({\an8} in SRT and ASS, line:0 in WebVTT). Colours, fonts and karaoke effects are dropped.

Example

An ASS line Dialogue: 0,0:00:02.50,0:00:04.00,Default,,0,0,0,,{\i1}Hello{\i0}\Nthere becomes the SRT cue 00:00:02,500 --> 00:00:04,000 with "<i>Hello</i>" and "there" on two lines. Converted to MicroDVD at 25 fps, the same cue is {63}{100} — 2.5 × 25 = 62.5 frames, rounded to 63, and 4.0 × 25 = 100.