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⏱️
⏪

Fix Subtitles That Lag the Audio

Advance subtitles that appear after the dialogue.

Nid oes angen mewngofnodiMae ffeiliau'n aros yn breifat

Drop a subtitle file (or paste below)

SRT, VTT, SBV, LRC, ASS, SSA, TXT dim cyfyngiad maint ffeil

Pori ffeiliau
0s

Positive delays the subtitles (use if they appear too early); negative advances them (if they lag the audio).

💡 Fixes subtitles that are out of sync — shift everything earlier or later, and correct frame-rate mismatches with the speed factor. The format is detected and preserved. Everything runs in your browser.

subtitles tips

⏪

If captions trail the speech, use a negative shift (e.g. −2s) to bring them earlier.

🎯

Find the delay by noting when a line is said vs when the caption appears, then shift by that amount.

🧪

Timings are clamped so nothing goes below 0:00.

🔒

Runs locally in your browser.

Sut Mae'n Gweithio

1
Dewiswch Ffeil
Drop your file into the tool above. It stays entirely on your device — nothing is sent to any server.
2
Proses
The tool processes your data instantly in your browser using JavaScript. No server, no waiting.
3
Lawrlwythwch
Get your result instantly. Nothing is stored after you leave the page — complete privacy.

Pam defnyddio ein un ni?

✓Hollol rhad ac am ddim - dim costau cudd, byth
✓Nid oes angen cyfrif, e-bost na mewngofnodi
✓Nid yw ffeiliau byth yn gadael eich dyfais
✓Dim cyfyngiadau maint ffeil o gwbl
✓Dim dyfrnodau ar unrhyw allbwn

Also check out…

⏩

Fix Subtitles That Appear Too Early

Delay subtitles so they line up with later audio.

🎞️

Fix Frame-Rate Subtitle Drift

Correct subtitles that slowly drift out of sync ov

✂️

Resync Subtitles for a Different Cut

Shift subtitles to match a version with a differen

🔤

Resync SRT, VTT, or ASS Subtitles

Shift timing in whatever subtitle format you have.

Cwestiynau Cyffredin

Back to Subtitle Shifter / Resync