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Subtitle Converter

Convert subtitles between SRT and VTT, shift their timing forward or backward, and fix frame rate drift to sync out-of-sync captions. Preview the parsed cues, catch format errors, and download the converted file.

Everything runs locally in your browser. Your data never leaves your device.

Format

Timing

Drop an .srt or .vtt file here, or click to browse
Cues3Ends at00:00:09.000

Cue preview

#StartEndText
100:00:01.00000:00:03.200Welcome back to the channel.
200:00:03.40000:00:06.000Today we are converting subtitles. Multi-line cues stay intact.
300:00:06.50000:00:09.000<i>See you in the next one.</i>

Next steps

Keep going. These tools open with your result loaded in.

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About the Subtitle Converter Tool

This tool converts subtitle files between SRT and WebVTT and fixes their timing. Paste the subtitles or drop in a .srt or .vtt file, and the format is detected automatically with a manual override when detection guesses wrong. The parsed cues show as a preview table with any format errors called out per cue.

The timing toolbox covers the two ways subtitles go out of sync. A constant shift moves every cue forward or backward, for subtitles that are simply offset. A linear correction stretches or compresses the timing, either from two anchor points or from a frame rate preset like 23.976 to 25 fps, for subtitles that drift further off the longer the video runs.

What you can do

  • Convert SRT to VTT and VTT to SRT.
  • Shift all subtitle timings forward or backward to fix an offset.
  • Fix progressively drifting subtitles with a two-anchor linear correction.
  • Correct framerate drift with presets like 23.976 to 25 fps.
  • Preview every cue with its timing and catch format errors per cue.
  • Renumber cues sequentially and download the result with the right extension.

How to use the Subtitle Converter

  1. 1Paste your subtitles, or drop a .srt or .vtt file onto the input.
  2. 2Check the detected source format and pick the target, or leave both on auto to flip the format.
  3. 3Fix the timing if needed: shift by a constant amount, or use a linear correction for drift.
  4. 4Review the cue preview and the conversion notes, then copy or download the result.

What survives the conversion

SRT and VTT share the basics, cues with start and end times and text, but each has features the other lacks. Converting to SRT drops VTT-only extras like cue position settings and voice tags, and converting to VTT translates what has a counterpart. The tool never drops anything silently: every removed or translated feature is listed in the conversion notes, so you know exactly what changed.

Offset or drift

Subtitles that are wrong by the same amount everywhere just need a shift, for example 2 seconds earlier because the video has a different intro. Subtitles that start fine and get worse over time have a speed mismatch, usually because the subtitles were made for a version of the video running at a different frame rate. For those, give the linear correction two anchor points, the time a line has now and the time it should have, near the start and near the end, or pick the matching frame rate preset. Cues in between are corrected proportionally.

Where the subtitles come from

SRT is the format most download sites and editors produce, while browsers and HTML video players only accept WebVTT, which is the most common reason for this conversion. The output keeps multi-line cues and simple styling tags intact. If the subtitles belong to a video you are editing anyway, the Video Trimmer and Video Converter handle the video side.

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