Subtitle Time Shifter

Upload a subtitle file and move every timestamp forward or backward by milliseconds or seconds to fix sync problems.

Drop your .srt or .vtt file here

Your subtitles are shifted locally in your browser. No upload required.

Time shift in milliseconds

Use positive numbers to delay subtitles, such as 1500 for 1.5 seconds later, or negative numbers to show them earlier, such as -500 for 0.5 seconds earlier.

Quick shifts:

Subtitles shifted successfully!

Shift summary
  • Processed subtitles: 0
  • Applied offset: 0 ms
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Create subtitles directly from a video?

Upload your video and automatically create SRT, VTT, or burned-in subtitles when you do not yet have a matching subtitle file.

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Why are my subtitles out of sync?

Subtitles can go out of sync when the video frame rate differs from the subtitle file, or when the video was edited after the subtitles were created. A simple time shift is usually enough when the delay is the same throughout the whole video.

How to sync SRT and VTT files

To fix a sync problem, open your video in VLC, YouTube Studio, or your editing software. Pause on a clearly spoken word, note the video timestamp, and compare it with the start time of the matching subtitle. The difference is your offset.

Calculate the offset: a practical example

The fastest way to find the right value is to compare the video time with the subtitle time. If a word is spoken at 01:05.500 in the video but the matching subtitle starts at 01:03.000, the subtitles appear 2.5 seconds too early.

Word heard in the video at
01:05.500
Subtitle starts at
01:03.000
Offset to enter
+2500 ms

Calculation: 01:05.500 minus 01:03.000 = 2,500 milliseconds. Because the subtitle appears too early, it needs to move later: +2500 ms.

How to use positive and negative time shifts

A positive value makes subtitles appear later. A negative value makes subtitles appear earlier. If you are unsure, start with a small value such as +500 ms or -500 ms and check the preview.

Problem Input Example Result
Subtitles appear too early +1500 ms 00:00:10,000 → 00:00:11,500 All subtitles are shown later.
Subtitles appear too late -800 ms 00:00:10,000 → 00:00:09,200 All subtitles are shown earlier.

Time Shifter or FPS Converter: which tool do I need?

A Time Shifter is made for a constant offset. If the subtitles are off by about the same amount at the start, middle, and end, a simple shift is enough. If the error grows over time, it is usually a frame-rate issue.

Situation Symptom Right tool
Constant offset Subtitles are about 2 seconds early or late throughout the video. Subtitle Time Shifter
Drift over time The beginning is correct, but by the end the subtitles are several seconds off. Subtitle FPS Converter

What happens to negative timestamps?

When you pull subtitles far forward, some cues may mathematically start before 00:00:00. Because negative timestamps are not valid in SRT or VTT, the tool offers two safe options.

Examples for VLC, YouTube, and Premiere Pro

The Time Shifter is useful whenever a finished subtitle file is generally correct but appears too early or too late in the video.

VLC / local players

If subtitles are consistently offset in VLC, measure the delay in the player and write that correction permanently into the SRT or VTT file.

YouTube uploads

If YouTube subtitles start at the wrong time after upload, correct the file with a fixed offset before uploading it again.

Premiere Pro

If an imported SRT no longer matches after a video edit, shift the subtitle file before import or fine-tune it in your editing timeline.

Safe and private

This Subtitle Time Shifter processes SRT and VTT files entirely in your web browser. Your files are never uploaded to our servers, so your subtitle data stays private.

Check the timing precisely after shifting

A global time shift fixes constant sync problems. If individual subtitles are still too long, too short, or awkwardly cut, open the file in Subvideo.ai Studio and review timing, text length, and readability directly on the video.

Check timing in Studio

How to shift subtitle timing

1

Upload subtitle file

Choose a SubRip (.srt) or WebVTT (.vtt) file from your device.

2

Set the offset

Enter the sync offset in milliseconds: positive to delay subtitles, negative to show them earlier.

3

Apply and download

Apply the time shift and download the corrected subtitle file.

Frequently asked questions

What is subtitle time shifting?

It means moving all subtitle timestamps forward or backward so they line up with the audio in the video.

How do I fix subtitles that appear too late?

Enter a negative value, such as -1500 ms, so the subtitles appear earlier on screen.

Does this work with both SRT and VTT?

Yes. It supports SubRip (.srt) and WebVTT (.vtt) files and keeps the correct millisecond separator for each format.

Are my files protected?

Yes. The time shift happens locally in your browser, without uploading your file to a server.

How do I calculate the right offset?

Compare the moment a word is heard in the video with the start time of the matching subtitle. If the word is at 01:05.500 and the subtitle is at 01:03.000, the offset is +2500 ms.

What happens if subtitles end up before 00:00:00?

You can either clamp those blocks to 00:00:00 or remove them. Clamping is safer if you do not want to lose text; removing is cleaner when the blocks are completely before the video starts.

When do I need an FPS Converter instead of Time Shift?

If the offset grows across the video, a fixed shift is not enough. The video and subtitle frame rates probably differ, so you should use the Subtitle FPS Converter.