How do I sync subtitles that are a few seconds off?

Measure the gap at the first spoken line, then apply that as a single time shift to every subtitle. If a line should appear at 00:05 but shows at 00:07, shift everything by -2 seconds. One offset fixes the whole file when the delay is constant.

Why do my subtitles start in sync but drift later?

Drift usually means a frame-rate mismatch between the subtitle file and your video (for example 23.976 fps vs 25 fps). A single shift won't fix it. Align the start first, then apply a second, smaller shift to the later section until the end matches too.

Can I sync subtitles without uploading my video?

Yes. SubtitleShift runs entirely in your browser, so your subtitle file and video never leave your device. That makes it faster and more private than tools that upload your files to a server.

What file format do I need?

SubtitleShift works with SRT (SubRip) files, the most common subtitle format. SRT files are supported by YouTube, VLC, Plex, Kodi and virtually every media player.

Do I need to install anything?

No. There's nothing to download or install. Open the editor, drop in your SRT file, adjust the timing and export. It works in Chrome, Firefox, Safari and Edge.

How to Sync Subtitles to Video (Fast, No Upload)

To sync subtitles to a video, measure how far off the timing is, then shift every subtitle by that amount so the text lines up with the audio. In SubtitleShift you drop in your SRT file, enter a time offset (like -2 or +1.5 seconds), apply it, and export a corrected file. The whole process runs in your browser and usually takes under a minute.

Quick version: find the delay at the first spoken line, enter it as a shift (negative if subtitles are late, positive if early), apply, then re-check near the end before exporting.

Why are my subtitles out of sync?

Before you fix the timing, it helps to know which kind of sync problem you have, because each is fixed differently. Most out-of-sync subtitles fall into one of two buckets.

Constant offset: every line is late (or early) by the same amount. This is the most common case and the easiest to fix with a single shift.
Progressive drift: the subtitles start roughly aligned but slowly fall out of sync, usually because the file was timed for a different frame rate than your video.
Edited-video mismatch: you trimmed an intro or cut a scene after the subtitles were made, so everything after the cut is off.

How do I sync subtitles to a video step by step?

1. Load your subtitle file

Open the SubtitleShift editor and drag your .srt file into the upload area, or click to browse. Your subtitles appear in a list with their timestamps and text. Nothing is uploaded to a server, so even unreleased or confidential content stays on your machine.

2. Measure the delay

Play your video and watch the first clear line of dialogue. Note the time the words are actually spoken versus the timestamp on the matching subtitle. The difference between those two numbers is your offset. If a line spoken at 00:05 is captioned at 00:07, your subtitles are 2 seconds too late.

3. Apply the time shift

In the Timestamp Shifter, enter the offset. Use a negative number to pull late subtitles earlier and a positive number to push early subtitles later. Apply the shift and every timestamp moves by exactly that amount. You can undo and try a different value until the opening line snaps into place.

Use millisecond precision when you need it. Values like -1.850 or +0.250 seconds are the difference between "close enough" and perfectly natural-feeling captions.

4. Check the end for drift

Once the start looks right, jump to the last quarter of the video and check a line there. If it's still aligned, you had a simple constant offset and you're done. If the end has slipped out of sync again, you're dealing with drift, which the next section covers.

5. Export the fixed file

When the timing holds up across the video, click Export. You get a clean SRT with UTF-8 encoding that works in VLC, YouTube, Plex, Kodi and any standard player. Keep your original file too, so it's easy to start over if you want to try different values.

How do I fix subtitles that drift over time?

Drift means the offset isn't constant, so a single shift can't fix the whole file. The practical approach is to correct it in two passes. First, shift the file so the very first line matches. Then measure how far off a line near the end is, and apply a second, smaller shift to bring the tail into line. Repeat with progressively finer adjustments until both ends and the middle all match.

If you know both frame rates involved, drift is predictable: subtitles timed for 23.976 fps played against 25 fps run gradually fast. Correcting the start and then nudging the end usually gets you close enough that no viewer will notice.

How do I sync subtitles after editing a video?

If you cut footage after the subtitles were created, calculate how much you removed and shift by that amount. Trim 5 seconds off the intro and every subtitle needs a -5 second shift. For a cut in the middle, only the lines after the cut are affected, so shift that range rather than the whole file.

Removed the intro: apply a negative shift equal to the seconds you cut.
Added an intro or logo: apply a positive shift for the new lead-in time.
Mid-video cut: shift only the subtitles that come after the edit point.

The fastest way to sync your subtitles

You don't need to install software or hand-edit timestamps in a text editor. Drop your SRT into SubtitleShift, shift the timing until the opening line matches, check the end, and export. It's private (nothing leaves your browser), free to start, and takes about a minute for most files.

Sync your subtitles now