How to open a subtitle file online
Three steps, a few seconds, no software.
Open your .SUB file
Drop it on the box, choose it from your device, or paste its text straight in.
View every line
See the start, end, duration and reading speed of each line, with any problems flagged.
Preview, fix, convert
Play the lines over your video, shift the timing, then download in the format you need.
What is a .SUB file?
Timed text that appears on top of a video.
A SUB file stores movie subtitles as plain text, either in MicroDVD format (frame numbers in braces) or SubViewer format (timecodes). To use it, give it the same name as the video and put both in the same folder; VLC loads it automatically. To convert to the more compatible SRT, use the free Subtitle Edit. If your SUB came with a .idx file, it is a different binary format (VobSub) and will not show readable text.
Programs that open .SUB files
| Full name | MicroDVD / SubViewer Subtitle File (text-based movie subtitles) |
|---|---|
| Developer | N/A (community/de facto formats: MicroDVD by the MicroDVD player team; SubViewer by SubViewer) |
| First released | late 1990s - early 2000s (DivX/MicroDVD era of PC video) |
| Category | Text & Code |
| MIME type | text/plain |
Related viewers
Every viewer is free to use.
Frequently asked questions
Is my .SUB file uploaded?
No. The file is read by your browser. If you preview with a video, the video is also played locally.
My .SUB file is out of sync. Can I fix it?
Yes. If they're early or late by a fixed amount, enter the difference in milliseconds and click Shift. If they drift more and more over time, the frame rate is wrong: use Change FPS (for example 25 → 23.976).
Why are some characters broken (é, ł)?
Older subtitles are often saved in a regional encoding like Windows-1250. We detect it automatically and every download is saved as UTF-8, which works everywhere.
What do the warnings mean?
Overlap: two lines on screen at once. Too fast: more than 20 characters per second. Too short: under 0.83 s. Long line: over 42 characters. 3+ lines: too much text at once.
Can I convert ASS to SRT?
Yes. Italic, bold and underline are kept; positioning and karaoke effects are dropped because SRT can't store them.
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