Subtitle Sync

Fix out-of-sync subtitles in seconds. Shift the entire file by ±N milliseconds, anchor the first and last cue to known timestamps for linear stretch, or rescale by frame rate. SRT, VTT, ASS, SBV, LRC.

Try the one-click demo

We synthesise a 5-second preview video and pair it with a subtitle that's deliberately 1 second early — so you can experience the off-by-one and the fix in one click.

Optional: video for live preview

optional

Subtitle file

Quick presets:

Tip: subtitles ahead of the speech? Use a negative offset to push them back.

Upload a subtitle (or try the demo) to enable these controls — adjustments preview live in the panel on the right.

What You Can Do With It?

Fix Global Subtitle Offset

When subtitles are consistently early or late, apply a global time shift in one click

Sync Downloaded Subtitles

Re-align subtitle files found online to match your local video timing

Align Translated Subtitles

Sync translated subtitle timestamps to match the original subtitle track

Fix Post-Edit Timing

Re-sync subtitle timelines that shifted after video editing or trimming

Fine-Tune Specific Segments

Adjust individual subtitle segments separately to fix localized timing drift

Calibrate Multilingual Tracks

Align subtitle timelines across multiple language files so all versions stay in sync

How To Use?

1

Upload Subtitle File

Upload the subtitle file that needs timing adjustment

2

Adjust Time Offset

Enter a global time shift or adjust specific segments individually

3

Export Synced Subtitles

Download the subtitle file with corrected timestamps

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Free online subtitle converter: turn SRT into VTT for HTML5 video, convert ASS subtitles to SRT for any player, batch convert dozens of files at once. Runs entirely in your browser — files never leave your device.

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Subtitle Crop

Crop subtitle bands from movie or TV screenshots and stack them into one vertical long image. Drag anchors on the first frame, align row order with per-segment previews, preview the full stitch, then download—all in your browser. Great for language study, dialogue archives, and meme frames.

View more

Frequently Asked Questions

If subtitles are uniformly N seconds early or late everywhere — use whole-file offset. If they start fine but drift further off as the movie goes on — use anchor first & last (linear stretch). The anchor mode handles 'wrong frame rate' subtitles perfectly.

Encountered other problems or suggestions? Have a bug or suggestion? Drop us an email.

Email Us

Out-of-Sync Subtitles: The 4 Most Common Causes in 2026

Downloaded subtitles that don't match the video are an eternal pain. MeTool's subtitle sync tool targets the pure-timing-mismatch family of problems (which is 80%+ of real-world cases) — no re-transcription, no AI re-alignment needed, fixed in seconds.

The four common causes and their fixes:

  1. Uniform delay or advance (most common, ~60% of cases) — every cue is 2.3 seconds late. Use "whole-file offset" with -2300 ms.
  2. Video has its intro removed — subs are early at the start, eventually drift in sync. Use whole-file offset with a negative value.
  3. Subtitles based on PAL 25 fps but your video is NTSC 23.976 fps (~25% of cases) — fine at the beginning, drifts further off as the movie goes on. Use "frame-rate convert" 25 → 23.976.
  4. OCR subtitles with irregular drift (~10% of cases) — extracted from hardsubs, head and tail drift by different amounts. Use "anchor first & last" — calibrate the first and last cue to their correct times; everything between is interpolated linearly.

Anything more complex (speech rhythm completely mismatched with the subtitles) needs a proper subtitle editor for line-by-line re-alignment, which is outside this tool's scope.

Why "Anchor First & Last" Is the Most Underrated Mode

Most subtitle sync tools only offer "whole-file shift," but a class of mismatch problems shift can't fix: opening lines are aligned, by 30 minutes the gap is 5 seconds, by 60 minutes it's 10 seconds.

This progressive drift usually comes from:

  • Subs based on the PAL 25 fps version, video is NTSC 23.976 fps (~4.3% speed difference)
  • Video has been speed-adjusted in an editor without re-syncing the subs
  • OCR'd subs where head-to-tail error accumulates

What's needed here is linear stretching, not a shift: pull the first cue to position A, pull the last cue to position B, and let everything between scale proportionally. That's exactly what MeTool's "anchor first & last" does.

Practical tip: play the video, find the real timestamp of the first spoken line (e.g. 00:00:08,500) and the last (e.g. 01:32:15,200), and put those in the "should appear at" fields. The whole file calibrates in one pass — far more accurate and far faster than tweaking line by line.

Frame-Rate Conversion: The Underused Fix for "Wrong-Cut" Subtitles

The same film exists in different frame rates by region: PAL 25 fps in Europe, NTSC 23.976 fps in North America, theatrical DCP at 24 fps. When subtitle frame rate doesn't match video frame rate, you get linear drift — the longer the runtime, the worse the end-of-movie offset.

Classic example: subs from a fansub site labeled "BluRay 24 fps" played against your "WEB-DL 23.976 fps" rip. The 0.024/24 ≈ 0.1% per-frame difference sounds negligible, but for a 2-hour movie that's an 8-second cumulative error — subs end up 8 seconds ahead of the speech.

MeTool offers seven common frame-rate presets: 23.976, 24, 25, 29.97, 30, 50, 60. Identify your subs and your video's frame rates:

  1. Subtitle frame rate: from the file name (e.g. The.Movie.2024.1080p.BluRay.x264-RARBG.srt implies 23.976 or 24) or the source site's notes
  2. Video frame rate: any media inspector — macOS Get Info, MediaInfo, VLC's "Codec Information"

For "subs 25 fps, video 23.976 fps", set source = 25 and target = 23.976. Every cue's time gets multiplied by 25/23.976 ≈ 1.0427, stretching the file to compensate for the too-fast subs.

Preserving Complex ASS Styling While Fixing Timing

ASS is beloved by fansub groups because it carries full styling: custom fonts, colored outlines, animations, karaoke highlights, positioning tags like \\pos, fade tags like \\fad. A tool that wipes that styling while "fixing the timing" effectively throws away hours of fansub work.

MeTool's subtitle sync handles ASS surgically: only the Start and End fields of each Dialogue line are recomputed; [Script Info], [V4+ Styles], [Fonts], [Graphics] all pass through verbatim. Style definitions, font tables, PrimaryColour, Outline color, KaraokeTimer, override tags — every byte is preserved.

Which means you can confidently:

  • Apply a whole-file offset to a finished fansub ASS
  • Frame-rate convert an ASS that contains OP/ED karaoke effects (e.g. BluRay subs onto a WEB rip)
  • Anchor-align hardsub-OCR'd ASS that you've manually styled

Original styling stays 100% intact — only the timing changes. SRT/VTT/SBV/LRC don't carry styling, so this section is specific to ASS.