Fix subtitles that are too fast or slow

If subtitles feel too fast or too slow, the first question is whether the whole file is offset by a fixed amount.

Quick answer

When every subtitle cue is consistently early or consistently late, a global time shift is usually enough.

Use the Subtitle Time Shifter or Subtitle Delay Fixer before assuming the file needs a full re-edit. If the problem grows over time, switch to the drift workflow instead of applying another delay.

What “too fast” or “too slow” usually means

People often describe sync problems in different ways:

• subtitles are too fast
• subtitles are too slow
• captions appear before the speech
• captions appear after the speech

Most of the time, they all point to the same underlying issue: the timestamps need to move earlier or later together.

Pick the right timing fix

What you see	What it usually means	Best first fix
Every caption appears before speech	Subtitles are early or ahead of audio	Add a positive delay to move all cues later.
Every caption appears after speech	Subtitles are late or behind audio	Add a negative shift to move all cues earlier.
The start is close but the end is wrong	Subtitle drift or frame-rate mismatch	Diagnose drift before using one global shift.
Only one scene is wrong	Timeline cut, removed intro, or inserted segment	Shift only that section with Partial Subtitle Shifter.

How to test the problem

Check three moments in the video:

1. near the beginning
2. around the middle
3. near the end

If the mismatch is about the same in all three places, use a global shift.

If the mismatch keeps growing, the file is drifting and needs more than one adjustment.

For a broader diagnosis, compare this guide with How to fix out-of-sync subtitles and Why subtitles drift out of sync.

Decide whether it is offset or drift

An offset problem is stable. A subtitle might appear 900 ms late at the start, middle, and end of the video. That is the easiest case because one global shift can repair the whole file.

A drift problem changes over time. The first cue might be close, the middle might be two seconds late, and the final cue might be five seconds late. That usually means the subtitle file was made for a different frame rate, a different edit, or a video with missing footage. Do not keep applying one global shift if the error keeps changing.

Step-by-step workflow

1. Measure whether subtitles are early or late.
2. Open the Subtitle Time Shifter.
3. Enter a negative value if captions need to move earlier.
4. Enter a positive value if captions need to move later.
5. Export the adjusted file and test again.

How to choose the shift value

Measure a cue against the spoken line it should match. The important part is the sign: positive values push captions later, while negative values pull them earlier. If the subtitle appears one second before the speech, use +1000 ms; if it appears one second after the speech, use -1000 ms.

After exporting, test at least three moments again. If the same amount is still wrong everywhere, adjust once more. If different parts are wrong by different amounts, use a partial shift or repair the edit-specific section separately.

Examples:

• Captions appear 800 ms before speech at the start, middle, and end: shift by +800 ms.
• Captions appear 1200 ms after speech at the start, middle, and end: shift by -1200 ms.
• Captions are close at 00:02:00 but 4 seconds late near the end: treat it as drift, not one delay.

When a global shift is not enough

A global shift only works when the same offset applies to the whole file. Stop and use a different workflow when:

• the beginning is fixed but the ending is still wrong
• the offset grows after every few minutes
• sync breaks immediately after a cut or removed segment
• the subtitle file was made for a different release of the video

Use Why subtitles drift out of sync for smooth timing drift, or Fix subtitle sync after a scene cut when the problem starts at one edit point.

Common mistakes

Adjusting line by line too early

Start with the global fix. Many “too fast” or “too slow” complaints are really just one offset problem.

Confusing delay with drift

If the error grows over time, a single shift will not hold.

Forgetting to re-test the end of the file

A file can look fixed in the first minute and still fail later.

When to use a partial fix instead

If the beginning and ending are correct but one scene is wrong, use How to shift only part of a subtitle file instead of moving the whole file. That workflow is safer after scene cuts, removed intros, inserted sponsor segments, or edits where only the middle of the timeline changed.

Related guides

• How to fix subtitle delay
• How to fix out-of-sync subtitles
• Fix subtitle sync after a scene cut
• Why subtitles drift out of sync

Related tools

• Subtitle Time Shifter
• Subtitle Delay Fixer
• Fix Out-of-Sync Subtitles
• Partial Subtitle Shifter