Fix Subtitles Online: SRT & VTT Errors, Timing and Overlaps
Upload a messy subtitle file. Get it back clean and correctly timed.
Upload an SRT or VTT file and get it back with overlaps, reading speed and line length fixed. Check it free first.
Supports SRT and VTT up to 20 MB. Your original file is never changed.
Free account, no card needed
Before
2 00:01:18,000 --> 00:01:18,400 The captions still overlap on the second line and run past the line limit.
After
2 00:01:18,000 --> 00:01:21,200 The captions still overlap on the second line.
What's wrong with your subtitles?
Find the problem you can see, then go straight to the tool that fixes it. The fixer on this page handles timing and layout; the other tools are free, need no account and run in your browser.
Captions overlap, lines run too long, or captions go by too fast to read
This page fixes these. Upload the file above: overlaps are ended, lines are re-wrapped to 42 characters, and fast captions get more time. To measure without changing the file:
The file won't load, or only some captions show
Usually a timing line in the wrong format, a missing blank line or broken cue numbers. Repair the structure in one click.
Letters show as é, ’ or gibberish like Ïðèâåò
The file was saved in a different text encoding. Detect it, preview the fix and save as UTF-8.
Every caption is early or late, or drifts further out of sync
A delay moves every caption by the same amount. A drift needs a stretch from one line near the start and one near the end.
You only want overlaps trimmed, with nothing else changed
Safe overlaps are trimmed in one click; the rest are explained so you can decide.
The SRT won't import into Premiere Pro
Find the exact line that breaks the import and fix it.
CapCut captions blink or overlap after re-import
Close the tiny gaps between captions and trim overlaps.
Your editor or player needs another format
Convert the file first, then fix it here.
Not sure what's wrong?
Check every line first. Each problem is listed with its line number, and nothing is changed until you choose to fix it.
What it fixes and what stays manual
The subtitle fixer handles timing and layout. Upload an SRT or VTT file and the fixer repairs errors like these. Fix timing and line breaks are on by default.
Overlapping cues
A cue that runs into the next one is ended before the next one starts. This happens only when Fix timing is on.
Cue timing
A cue that ends at or before its start is given an end time after it. With Fix timing on, you can also move every cue earlier or later by a fixed number of milliseconds.
Line breaks
Text is re-wrapped at word boundaries onto at most two lines. A cue that still does not fit is split into more cues.
Long lines
Lines are kept to 42 characters. A single word longer than that stays as it is and is reported.
Reading speed
Cues faster than 20 characters per second get more time where the next cue allows it, up to 10 seconds per cue.
What stays manual: wording and translation errors. The fixer does not check whether the words or the translation are right; the optional grammar fix corrects spelling, grammar, casing and punctuation, not meaning. Anything it cannot repair safely is listed with where it is, for you to fix by hand.
Every check and fix, with its threshold and source
Is it free?
Guest: Check any SRT or VTT file without an account. A free account shows what we found and lets you fix and download. Free account: See every finding, fix the file, and download each fixed file up to 2 times. Free SRT and VTT downloads include two short VideoText watermark cues, one at the start and one after the last cue. Each fix counts toward your free plan's daily allowance. Pro: No watermark, cue editing, and PDF and Word export. No daily cap; a fair-use pause applies after 60 uploads in a minute. Pro is $14.99/month or $120/year, and regional prices can differ.
Tested on 11,597 injected defects
Evaluated on 2,000 synthetic subtitle files containing 11,597 injected defects. The VideoText subtitle engine detected all injected defects and produced compliant output for 99.2% of files containing repairable defects. DOI 10.5281/zenodo.23701131
A reproducible benchmark published by VideoText on Zenodo, not an independent peer review. Where a defect could not be repaired safely, the fixer left it and reported it.
How to fix a subtitle file
4 steps
1. Upload SRT or VTT
Up to 20 MB. Checking is free.
2. See what's wrong
Overlaps, reading speed, cue length and line length, counted and listed.
3. Fix
Choose what to repair. Fixing needs a free account.
4. Download
Your fixed file, plus anything that still needs a person, listed with where it is.
What the subtitle fixer repairs
6 capabilities
Overlaps
Cues that start before the previous one ends.
Reading speed
Cues faster than 20 characters per second get more time where the next cue or a verified video duration allows it, capped at 10 seconds. Extending the last cue without a video is reported for you to check.
Line length
Re-wraps lines to 42 characters at word boundaries.
Timing shift
Move every cue earlier or later by milliseconds.
Grammar and fillers (optional)
AI spelling, casing and punctuation fixes, and optional filler-word removal.
Scene cuts
With the source video, flags cues that cross a camera cut.
Real example
Real before and after. 2 examples
Cue 1 was a single 93-character line and cue 2 ran 0.4 s into cue 3. VideoText re-wrapped every line to 42 characters or fewer at word boundaries and ended cue 2 at 9.900 s so it no longer overlaps. The wording was not changed. The report listed 10 automatic fixes.
Source clip: NASA ScienceCasts, public domain. NASA does not endorse VideoText.
Real output · overlap and line length fixed
2 00:00:06,400 --> 00:00:10,400 study it from orbit, and ultimately bring back a sample for lab testing. 3 00:00:10,000 --> 00:00:12,480 a laboratory study on Earth.
2 00:00:06,400 --> 00:00:09,900 study it from orbit, and ultimately bring back a sample for lab testing. 3 00:00:10,000 --> 00:00:12,480 a laboratory study on Earth.
Cue 2 now ends at 9.900 s instead of running into cue 3; lines are wrapped at 42 characters.
Real output · overlap, long line and fast cue fixed
1 00:00:01,000 --> 00:00:05,000 Welcome back. Today we fix a subtitle file with a few problems. 2 00:00:04,600 --> 00:00:06,500 This cue starts before the last one ends. 3 00:00:07,000 --> 00:00:07,500 This line is far too fast to read. 4 00:00:09,500 --> 00:00:11,500 The last cue is fine.
1 00:00:01,000 --> 00:00:04,500 Welcome back. Today we fix a subtitle file with a few problems. 2 00:00:04,600 --> 00:00:06,650 This cue starts before the last one ends. 3 00:00:07,000 --> 00:00:08,700 This line is far too fast to read. 4 00:00:09,500 --> 00:00:11,500 The last cue is fine.
Run with the default settings (Fix timing and line breaks on). Cue 1 ran 0.4 s into cue 2; it now ends at 4.500 s, and its 63-character line is wrapped at a word boundary. Cue 3 showed 34 characters for 0.5 s (68 characters per second); it now ends at 8.700 s, which brings it to 20. Cue 2 (21.6 characters per second) now ends at 6.650 s. The wording was not changed.
Who uses the subtitle fixer
QC before delivery, After translation, Inherited files
QC before delivery
Clear overlap and reading-speed failures before a client or platform does.
After translation
Translated lines run longer; fix reading speed and line length afterwards.
Inherited files
Repair subtitle files from other tools or vendors.
Frequently asked questions
12 questions
What does a subtitle fixer do?
It repairs overlapping cues and cue timing, gives cues faster than 20 characters per second more time where the next cue allows, and re-wraps text onto at most two lines of 42 characters, splitting a cue that still does not fit. Optional AI fixes correct spelling, grammar and punctuation and remove filler words. Anything it cannot repair safely is listed with where it is, for you to fix by hand.
How do I fix an SRT file online?
Upload the SRT, review what the check found, choose the fixes and download the fixed file. Checking is free without an account; a free account shows the findings and lets you fix and download.
How do I fix overlapping subtitles in an SRT file?
Upload the file and run the fix. Overlapping cues are separated so only one shows at a time.
Why do my subtitles overlap?
A cue's end time runs past the next cue's start, which often happens after editing, merging files or automatic timing. With Fix timing on (the default), each such cue is ended before the next one starts.
Can I check my file before fixing it?
Yes. Checking is free and never uses an import. It lists every issue without changing the file; sign in with a free account to see the results.
What does it change, and what does it leave alone?
It changes timing and line breaks to fix the issues you choose. Your wording changes only if you turn on grammar fixes or filler-word removal.
How do I fix subtitles that are out of sync by a fixed amount?
Use the timing shift to move every cue by a number of milliseconds (negative is earlier).
What reading-speed and line-length rules does it use?
20 characters per second (the same default as the reading-speed checker), 10 seconds maximum per cue, and 42 characters per line. 17 and 21 remain comparison presets on the reading-speed checker. This is not a Netflix, BBC, or EBU certification.
Does it work with VTT files?
Yes, SRT and VTT up to 20 MB.
Is the subtitle fixer free?
You can check any SRT or VTT file without an account. With a free account you see every finding, fix the file, and download each fixed file up to 2 times; free downloads include two short VideoText watermark cues, and each fix counts toward your free plan's daily allowance. Pro removes the watermark and adds cue editing and PDF and Word export.
What's the difference from the Subtitle Validator?
The validator checks SRT and VTT files in your browser and repairs only problems with one correct answer, in SRT files. The fixer also re-breaks lines and fixes timing and reading speed, and needs a free account to see results.
Has the subtitle fixer been tested?
Yes. In a reproducible benchmark of 2,000 synthetic SRT files with 11,597 injected defects, it detected every defect and produced compliant output for 99.2% of files with repairable defects. It is published by VideoText on Zenodo (DOI 10.5281/zenodo.23701131), not independently peer reviewed.
Next steps for your subtitles
- Translate subtitlesAnother language with the same timing.
- Style and burnBurn the fixed captions into your video.
- Subtitle ValidatorCheck a file without changing it.
- Shift subtitle timingPure offset fixes.
- Fix SRT FileFile won't load or shows half the captions? Repair its structure, free.
- Fix Subtitle EncodingGarbled letters like é or Ïðèâåò? Save the file as UTF-8, free.
Fix your subtitle file
Check it free, then fix overlaps, reading speed and line length.
Upload SRT to Fix