SUB to SRT converter

Turn .sub subtitle files into SRT, the format almost every player and editor supports. Works with MicroDVD and SubViewer files, converted on your device.

Only used if the file doesn't state its own.
    Original
    Original
    Result
    Result

    Three kinds of .sub file

    Type Looks like Timing Supported
    MicroDVD {250}{300}Hello there Frame numbers Yes
    SubViewer 00:00:10.00,00:00:12.00 then text Times Yes
    VobSub Binary, with an .idx file Pictures from DVDs No (needs OCR)

    The converter detects which kind you have automatically.

    How to convert SUB to SRT

    1. Choose the frame rate of the video the subtitles are for. 23.976 is right for most films and series.
    2. Choose your .sub files or drop them on the box above.
    3. Download the .srt files and check the timing against your video.

    Formatting

    MicroDVD line breaks, written as |, become real line breaks. A line starting with / is italic and becomes <i>…</i>. Other MicroDVD style codes in braces, such as colour and font, are removed because SRT doesn’t support them. SubViewer [br] line breaks are converted too.

    Why convert to SRT

    SRT is the most widely supported subtitle format: VLC, Plex, smart TVs, YouTube and every major video editor accept it. Many newer players no longer read MicroDVD files, or read them with the wrong timing because they guess the frame rate.

    Fine-tuning the sync

    If the subtitles are only slightly early or late by the same amount throughout, the frame rate is right and the offset is the problem. In VLC, press H to make subtitles appear later or G to make them appear earlier while the video plays, in steps of 50 milliseconds. Subtitle editors such as Subtitle Edit can then shift the whole SRT permanently.

    If the difference grows over the course of the film, the frame rate is wrong instead: convert again with another frame rate.

    Privacy

    Subtitle files are converted in your browser and never uploaded.

    Questions

    Why does a SUB file need a frame rate?

    MicroDVD .sub files time each subtitle by video frame number, not by seconds. Frame 250 is 10 seconds into a 25 fps video but about 10.4 seconds into a 23.976 fps one. Choose the frame rate of the video the subtitles belong to; if the file states its own rate, that is used instead.

    How do I find my video's frame rate?

    In VLC, open the video and choose Tools › Codec Information. On Windows, right-click the file, choose Properties › Details. Films and series are usually 23.976 fps, European TV 25 fps, American TV 29.97 fps.

    The subtitles drift out of sync. What's wrong?

    The frame rate doesn't match the video. If subtitles appear gradually earlier or later as the video goes on, convert again with a different frame rate, usually switching between 23.976 and 25.

    Can it convert VobSub .sub files with an .idx file?

    No. VobSub files, ripped from DVDs, store subtitles as pictures, not text. Turning them into text needs OCR, which this tool doesn't do, and you'll see a message saying so.

    Last reviewed 8 November 2026