In Shotcut, subtitles usually drift out of sync because of when you created them, not how. The official Shotcut User Guide names the cause in a single sentence, and once you have read it the fix stops being a setting to hunt for and becomes a change in the order you work.
What actually breaks subtitle sync
Shotcut's Subtitles panel attaches subtitle items to the timeline, not to individual clips. The User Guide is explicit about both the restriction and what follows from it:
"Subtitles can only be added to the Timeline. They can not be added to the playlist or clips. We recommend to save subtitle editing until the timeline editing is complete because moving or cutting clips on the timeline will break the subtitle synchronization."
Read the second half again, because it is the whole answer: moving or cutting clips on the timeline will break the subtitle synchronization. The guide does not present that as an edge case or a bug. It is the documented consequence of editing the timeline after your subtitles exist.
That also explains the shape people describe. Sync is fine at the head of the video and gets steadily worse further in, because the offset accumulates from every second you added or removed earlier in the edit.
The guide also describes where the track sits and how multiples behave: "After the subtitle track is created the subtitle track area will appear in the timeline above the top video track. Multiple subtitle tracks can be added. But only the currently selected subtitle track is shown in the Subtitle Panel and the Timeline." If you corrected timings and the panel still shows the old ones, confirm which subtitle track is currently selected — only that one is displayed. For reference, the guide notes "The Subtitles Panel was added in Shotcut 24.08", so on older builds the panel is not there at all.
The fastest fix: change the order you work in
Because the cause is a workflow problem, the fix is a workflow rule:
- Finish the timeline completely first — every cut, trim, ripple delete, reorder and clip swap.
- Then create or import the subtitle track.
- Treat any later timeline edit as a reason to re-check sync, since the guide says that is precisely what breaks it.
If you are already past that point and have both subtitles and a re-edited timeline, the practical route is to take the subtitles out of Shotcut, fix the timing in a plain text editor, and bring them back. The guide confirms both directions: "Subtitles can be exported to a file. Subtitles are exported in SRT format." Import is broader — "Supported subtitle import formats include: SRT, VTT, ASS, and SSA."
There is a trap on the way back in, and it is the second most common sync complaint. The guide states: "Subtitles are imported at the current cursor position." It then adds that you should be sure to place the cursor before importing subtitles from a file. If your entire subtitle file lands with a constant offset — everything late by the same amount, no drift — that is almost always this, not the clip-editing cause above. Move the playhead to the start of the timeline and import again.
Once the SRT timings are right, you do not have to rebuild the whole Shotcut project just to see them on the picture. You can burn a corrected SRT straight onto the video here:
Try it right here
Runs in your browser. Your file is not uploaded anywhere.
This runs in your browser, so the video and the subtitle file stay on your machine. It is also the quicker path when the only thing left to do is a hardcoded caption layer — see burn subtitles to video for the standalone tool.
Other causes, in order of likelihood
Non-integer project frame rate. Shotcut's release notes record "Fixed Subtitles works incorrectly after a couple of minutes with non-integer frame rates." as of Release 25.01.25. The symptom is distinctive: the first minute or two look fine, and it falls apart after that. If you are on a build older than that release and your project runs at a broadcast rate such as 30000/1001, update before you spend an evening nudging timings.
Variable frame rate source footage. The guide has a whole section on this and describes the symptoms directly: "Sometimes users report that Shotcut is not frame accurate. For example, they split a clip on a certain frame, but then later the split is not where they expected it... Also, sometimes people report that the audio and video out not in sync." To identify it: "If the clip frame rate does not match a standard frame rate, then it is probably VFR. If Shotcut is able to detect a VFR clip, it will add a "(variable)" tag after the frame rate. But Shotcut can not always detect VFR clips." The remedy the guide gives is "The best way to edit VFR clips is to convert them to a fixed frame rate", and its first step is to set Settings > Video Mode yourself — the guide specifically says not to use Automatic.
Automatically generated subtitles starting early. If the track came from Speech To Text rather than a file, the guide lists this under known quirks: "Subtitle items sometimes start earlier than expected. Timing is provided by the model and tool, and we lack the skills and resources to improve this." That is Shotcut telling you the early starts are expected behaviour from the model, so budget time to nudge the in-points by hand.
Sub-frame level errors. The release notes record "Fixed off-by-one frame errors in subtitle bar in Timeline and Subtitle Burn In video filter." as of Release 26.8.1. A single frame is not what anyone means by "out of sync" in conversation, but if you are matching captions to a hard cut it matters — and it is worth ruling out before assuming your own timings are wrong.
Exporting a marker range. The release notes also record "Fixed using Export > From > Marker with subtitles creates a bad output (broke in v24.08)." as of Release 24.11.17. If your bad output only appears when exporting a range marker rather than the full timeline, check your version against that release.
How to tell it worked
Scrub to the end of the timeline, not the start — accumulated drift is invisible in the first thirty seconds and obvious in the last. Check one subtitle near the beginning, one in the middle and one at the end. If all three land, the offset is gone rather than merely moved.
FAQ
Why do my Shotcut subtitles drift further out as the video goes on? Because you edited the timeline after adding them. The user guide states that moving or cutting clips on the timeline will break the subtitle synchronization, and the error compounds with every edit earlier in the sequence.
My whole subtitle file is late by the same amount — is that the same problem? Probably not. A constant offset with no drift points at the import position: subtitles are imported at the current cursor position, so the playhead was not at the start when you imported. Reposition it and import again.
Can Shotcut export my corrected subtitles as WebVTT? No. The user guide says subtitles are exported in SRT format, while import accepts SRT, VTT, ASS and SSA. If you need VTT for the web, convert the exported SRT afterwards with SRT to VTT.
My subtitles are in sync in the preview but missing from the export. That is a different failure. The guide says subtitles will be embedded in the output file if the file format supports it, and lists MKV, MOV and MP4 as formats that commonly support subtitles. For a hardcoded overlay instead, the Subtitle Burn-In filter "can only be added to the Timeline Output" — adding it to a clip is the usual reason it appears to do nothing. See Shotcut export failed for the wider export troubleshooting path.
Does re-importing the SRT re-sync everything automatically? Only if the timings in the file are already correct for the current timeline. Shotcut places the items where the file says, at the cursor — it does not re-align them to your clips.
Fix the timeline first, subtitles second, and most of this never happens. When the timing is already right and you only need the captions rendered onto the picture, do it in the browser instead of rebuilding the project — the full set is at all Clapr tools, and more Shotcut troubleshooting lives in the fix guides.
Quotations above are from the official Shotcut User Guide (June, 2026) and the Shotcut release notes, as captured in September 2026. Release-note entries describe what changed in that version — check the current official documentation for the state of your build.
