Resync subtitles to the audio when a simple shift does not fix them
Subtitles that start in sync and slowly drift, or that come from a release with different cuts, cannot be fixed by moving everything a few seconds. Upload the video or audio with the SRT or VTT and each cue is timed again from the speech, with its text and line breaks left alone. Files of up to 10 minutes are free in full; a longer one costs $5, paid once.
- SRT, VTT, ASS, SBV or LRC in; SRT and VTT out
- Cue text and line breaks unchanged, only start and end times replaced
- Each cue timed on its own, so growing drift and changed scenes are both handled
- Video or audio up to 6 hours per job, 12 on Unlimited
- No audio at hand? Fix Subtitle Sync can shift, stretch or convert the frame rate
Why a fixed offset is not enough
The subtitle delay in a player, or any offset tool, moves every cue by the same amount. That works when the whole file is early or late by one margin. It fails when the gap grows over time, which usually points to a frame-rate mismatch, or when it jumps at certain moments, which means your copy is a different cut: a longer intro, a removed recap, an extra scene.
Stretching repairs steady drift but not jumps. Resyncing makes no guess about the pattern. Speech recognition finds when each word is spoken in your copy, and every cue is matched to the words it contains, so it lands where its line is said whether the error was half a second or a whole scene.
Resync or shift: which one you need
- Same delay from start to finish: a shift in Fix Subtitle Sync is quicker and needs no video upload
- Gap growing at a steady rate, for example 25 against 23.976 frames per second: Fix Subtitle Sync can stretch or convert the frame rate without audio
- Gap changing at scene cuts, or subtitles from another release: resync from the audio here
- No idea why it is off: resync here, check the free part, and compare
What changes in your file
Only the times. The words of every cue, how they are split across lines and their order stay as they were. Styling tags, such as italics or ASS positioning, are not carried over, because the result is plain SRT or VTT. Cues come back in order, never overlap, and each stays on screen long enough to read.
A cue for something not spoken in your copy, such as dialogue from a scene this version lacks, has no speech to land on and gets squeezed next to the cues around it. Captions for on-screen signs and notes like [door slams] have the same problem. Delete such cues first if you know where they are.
The language has to match the audio
Resyncing compares the words in each cue with the words that are spoken, so the subtitles must be in the language of the soundtrack. A translated SRT has nothing to match against. For a translation that drifts, resync the original-language subtitles first, or use a shift or stretch in Fix Subtitle Sync. Timing in Amharic, Tigrinya, Somali, Dari, Kurdish, Burmese and Pashto comes from a general AI model and is less exact.
How the tool works, what it costs and how your files are handled is on the Sync Transcript to Audio page; prices for every tool are on the pricing page.
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Questions and answers
Can ChatGPT fix my out-of-sync subtitles?
If you know the offset, a chat assistant can add or subtract it from every timestamp in a short file, and that often works. It cannot watch the video, so it cannot find where a cut changes the gap, and with a full-length SRT it tends to stop partway or alter lines. Resyncing here gives every cue a time taken from the audio.
Can I resync subtitles from another release of the same film?
Yes, as long as the dialogue is the same. Scenes that exist only in your copy simply end up without cues. Cues for scenes your copy does not have should be removed first.
Do the subtitles have to be in the spoken language?
Yes. The cue text is matched to the words in the audio, so a translated file cannot be resynced this way. Use Fix Subtitle Sync for an offset or stretch instead.
Will my line breaks stay the same?
Yes. Each cue keeps its text split exactly as in your file; only the start and end times are new. Formatting tags are dropped.
How much does resyncing cost?
A video of up to 10 minutes is resynced free in full. A longer one, such as a feature film or an episode, is $5 once for up to 6 hours. Unlimited costs $19 a week and covers up to 12 hours per job.
Is my video shared anywhere?
No. Only you can open the job. The file is sent to an AI model provider only to be processed and is not used to train models. Jobs started without an account are deleted after 7 days, and you can delete one yourself at any time.