Subtitle Converter With Encoding and Timing Repair

The file was not UTF-8. Subtitle files carry no declaration of their own encoding, and older ones almost never are: Russian .srt files are typically windows-1251, Polish and Czech windows-1250, French and Spanish windows-1252, Chinese Big5 or GBK. Any program that reads such a file as UTF-8 mangles every non-ASCII letter. Here the encoding is worked out from the bytes and shown in the Encoding block; if the letters still look wrong, switch it by hand and the preview updates at once, so you can see which one is right.

MicroDVD (.sub), Spruce STL and Apple ITT store frame numbers rather than time, so they cannot be read without a frame rate. Some files declare it on the first line as {1}{1}23.976, and that is used when present. When it is absent, open the Frame rate block and choose: 23.976 for most modern releases, 25 for European broadcast versions. The same block prints the moment the last cue lands on — compare it with the length of your video and you will know immediately whether the rate is right.

Italics, bold, underline and color carry over. What does not is everything SRT has no room for: on-screen position and alignment (beyond top/bottom, which survives into VTT and TTML), fonts and sizes, karaoke timing, effects, and the vector sign-typesetting lines — those are dropped whole, because their "text" is drawing coordinates rather than words. The line under the format grid lists the losses before you download rather than after.

Usually the format is not the problem. Check in this order: the filename matches the video up to the extension (Movie.mkv and Movie.srt; a language suffix such as Movie.en.srt is fine); the file is saved as UTF-8 — that is the Encoding block here, and very old TVs sometimes need the "UTF-8 + BOM" variant; the file actually contains cues, which the counter above the format grid reports; and the timecodes are neither reversed nor overlapping, which the Clean-up block repairs. For the video tag on a website the format has to be VTT specifically — browsers do not read SRT.

YouTube accepts SRT, SBV and VTT — use SRT. Premiere Pro, DaVinci Resolve and Vegas work with SRT. Final Cut Pro expects .itt, the Apple profile, which is written against the frame rate of your project, so that rate has to be chosen. For the video tag on a website, VTT. For streaming platforms and broadcasters, DFXP or TTML. The "Where are these subtitles going?" row on the first screen sets the format for you.

It is reading speed — how many characters a second the viewer has to get through. Seventeen characters per second for adult content and thirteen for children's comes from the Netflix style guide the industry generally follows, along with 42 characters per line and no more than two lines. Character-based languages are measured against a different limit, because one character there carries roughly a word. The "Fix the timings" button lengthens cues into the silence around them but never touches the words: shortening a translation is the translator's job, not a program's.