How to repair broken video files, by symptom

Sound plays, screen is black

Most often it’s a codec your player doesn’t support, usually HEVC. Try VLC. If VLC shows the picture, install the HEVC extension (Windows) or convert to H.264. If VLC is also black, the video track may be damaged or missing from the index. See our black screen page.

Picture plays, no sound

Check whether the audio is in a format your device doesn’t handle (PCM in a MOV, for example). If the audio track is listed but silent, the index for it may be broken, and a remux often fixes it. See video no sound.

Stuck at 0:00 or won’t open

This is the missing-index case: the recording was interrupted before it finished. Rebuild the index, ideally using a good clip from the same camera. See the moov atom explained.

Freezes partway, or skips

The file is truncated or has damage in the middle. Save what plays with a remux, or re-encode to smooth over glitches. See damaged MP4 repair.

Plays fine but won’t import into an editor

Editors are pickier than players. Variable frame rate from phones and screen recorders trips up Premiere and some versions of DaVinci Resolve. A remux with -movflags +faststart sometimes helps. Converting to a constant frame rate fixes it reliably.

Not sure which one you have?

Open it in our repair tool. The free diagnosis names the problem, and the preview shows you the fix before you pay.

Broken how? Five common situations

“Broken” covers a lot of ground. Before trying a fix, match your situation to one of these, because each has its own best repair.

The video won’t open at all. Players show an error, or nothing happens when you double-click.

The video opens but shows no picture, only sound, or only a picture with no sound.

The video plays but stops early, jumps, or freezes partway.

The video plays but looks broken: blocks, smears, green or pink screens, stuttering.

The video plays fine on one device and not at all on another.

The video won’t open at all

Check the file size and try VLC. If VLC opens it, the file is fine and your usual player is the problem. If VLC can’t, the file’s structure is broken.

For MP4 and MOV files, a broken structure almost always means a missing index after an interrupted recording. Rebuilding the index brings the full video back losslessly. For MKV and WebM, a remux usually fixes it. For AVI, VLC’s built-in index repair or a remux works.

If the file is zero bytes or a tiny fraction of the expected size, it isn’t repairable; look for the original.

Sound but no picture, or picture but no sound

Sound with a black picture usually means the player can’t decode the video codec. HEVC (H.265) is the usual suspect on Windows, AV1 on older devices, and ProRes on most non-Apple players. Try VLC, which includes software decoders for all of them.

If VLC also shows black, the video track may be missing its codec setup data. That happens when an index is rebuilt without the right information. Rebuilding again with a reference clip from the same camera supplies the missing setup and usually brings the picture back.

Picture with no sound is often an audio codec issue, such as PCM, AC-3, or Opus audio in an MP4 that the player doesn’t support. Re-encode just the audio: ffmpeg -i in.mp4 -c:v copy -c:a aac out.mp4. If the audio track is missing entirely, the repair didn’t recover it; try a rebuild with a reference clip.

Stops early, jumps, or freezes

If the video always stops at the same point, the index only covers part of the file. Check whether the file size is much larger than the playable length suggests. If so, rebuilding the index from the raw data recovers the rest.

If the video jumps forward, a section of data may be missing, from a damaged card sector or a fragmented recovery. Nothing can restore it, but a clean remux makes the jump smooth rather than crashing the player.

If the picture freezes while sound continues, the video frames in that section are damaged or missing while audio survives. Cutting the section or re-encoding to conceal it are the options.

Blocks, smears, and coloured screens

These are the visible signs of damaged frame data. They usually appear suddenly, spread across the picture, and clear up at a scene change or after a second or two, when the next keyframe arrives.

If the problem appears in many places throughout the video, the storage is probably failing. Copy everything off the card or drive and replace it.

A full green or pink screen for the whole video is different: it usually means the decoder is using the wrong settings, often after a repair with an incorrect reference file. Re-run the repair with a reference recorded at exactly the same resolution, frame rate, and colour profile.

Works on one device, broken on another

This is almost never file damage. It is codec or format support. A phone records 10-bit HEVC with HDR; an older laptop or TV can’t decode it. A Mac records ProRes; a Windows PC lacks the codec. A screen recorder writes MKV; QuickTime refuses MKV.

Solutions: install a capable player such as VLC or MPV; install missing codecs (the HEVC Video Extensions on Windows); or convert the video to a widely supported format, 1080p H.264 with AAC audio in an MP4. Conversion re-encodes and slightly reduces quality, so keep the original.

Repairing broken videos with one tool

If you’d rather not diagnose by hand, our repair page inspects the file, picks the right fix, and shows you a free 15-second preview of the result. It handles missing indexes, broken headers, and timing problems in MP4, MOV, and related formats. If the preview looks good, unlock the full file for $9/month or $29/year.

For more detail on specific formats, see fix a corrupted video. For damage grading and what to expect, see damaged MP4 repair.

Free tools for repairing broken videos

VLC Media Player: plays almost everything, rebuilds AVI indexes on the fly, and can convert broken files with its Convert/Save feature. The first thing to install.

FFmpeg: the command-line Swiss army knife. Remuxes, fixes timestamps, extracts streams, and checks for errors. Most other tools use it internally.

MKVToolNix: the best tool for MKV and WebM files. Its MKVToolNix GUI can remux broken MKVs and fix headers.

untrunc: rebuilds missing MP4 and MOV indexes using a reference file. Excellent for interrupted phone and camera recordings.

HandBrake: a friendly re-encoder. Useful as a final step to turn a repaired file with odd timing into a clean, compatible MP4.

MediaInfo: shows detailed information about any video file, helpful for checking codecs and comparing broken and reference files.

Repairing a broken video step by step with FFmpeg

1. Inspect: ffprobe -hide_banner broken.mp4. Note any errors.

2. Remux: ffmpeg -i broken.mp4 -c copy -movflags +faststart remux.mp4. If it succeeds, test the result.

3. Skip errors: ffmpeg -err_detect ignore_err -i broken.mp4 -c copy skip.mp4. Use if the remux stops at damaged data.

4. Fix timing: ffmpeg -fflags +genpts -i broken.mp4 -c copy timing.mp4. Use if the video plays at the wrong speed or has a wrong duration.

5. Re-encode: ffmpeg -i broken.mp4 -c:v libx264 -crf 18 -c:a aac reencoded.mp4. Use as a last resort for damaged frames or incompatible codecs; it takes longer and slightly reduces quality.

If step 1 says the moov atom is missing, none of these will work. You need an index rebuild instead; see how to fix corrupted MP4 files.

Repairing broken videos with HandBrake

HandBrake reads anything FFmpeg can read and writes clean MP4 or MKV files. It is a good fix for videos that play but behave oddly: wrong rotation, variable frame rate causing sync drift, unusual codecs, or broken timing.

Open the video, choose the Fast 1080p30 or HQ 1080p30 preset, set Framerate to Same as source with Constant framerate selected, and start the encode. The result is a widely compatible file with regular timing.

HandBrake can’t open a video with a missing index, though. For those, repair first and then use HandBrake for any final clean-up.

Repairing broken videos online

Online repair saves installing anything, but choose carefully. Check that the service shows you a preview before paying, explains what it does with your files, and deletes them after processing. Avoid services that ask you to install a browser extension or a downloader.

Our repair page processes MP4 and MOV files on your device where possible and on our servers otherwise, shows a free 15-second preview of the repaired video, and charges only if you unlock the full file: $9/month or $29/year.

Which broken videos can’t be repaired

Files with no video data, such as zero-byte files or files full of zeros. Files encrypted by ransomware, which need a backup or the decryption key. Files overwritten by other data. Files on physically destroyed media, which need a recovery lab first.

Everything else is worth a try. Even heavily damaged videos often yield usable sections. See damaged MP4 repair for what to expect at each level of damage.

Broken videos on phones

On iPhone, a video that shows a spinner or an exclamation mark in Photos usually hasn’t finished downloading from iCloud. Connect to Wi-Fi, keep the phone charged, and wait. If it still fails, check iCloud.com in a browser; if the video plays there, download it to a computer.

On Android, a video that won’t play in Gallery may play in VLC for Android or Google Photos. If none play it, and the file size looks right, it was probably interrupted during recording and needs an index rebuild on a computer or through the repair page.

Videos received in chat apps are copies. If a received video is broken, ask the sender to send it again rather than repairing the copy.

Broken videos from old tapes and DVDs

Digitised home videos, captured from VHS, MiniDV, or DVD, often come as AVI, MPG, or VOB files. Broken captures usually have timing problems or missing indexes rather than damaged frames. A remux to MKV or MP4 usually fixes playback: ffmpeg -i capture.avi -c copy capture.mkv.

DVD VOB files that won’t play individually can usually be joined and remuxed: ffmpeg -i "concat:VTS_01_1.VOB|VTS_01_2.VOB" -c copy movie.mpg. Scratched DVDs need a ripping tool with error tolerance, such as ddrescue on the disc, before any file repair.

MiniDV captures in DV AVI format are very robust because every frame is independent. Damaged frames simply drop out without affecting the rest.

Repairing broken videos for uploading

YouTube, Vimeo, and social platforms reprocess everything you upload, so they tolerate many minor problems. But a missing index, broken timestamps, or a truncated file can make uploads fail or produce a video that stops early.

Repair the file first, then do a final check: play it start to end, confirm the duration, and confirm audio sync. If the platform still rejects it, re-encode with HandBrake’s Fast 1080p30 preset, which produces files that every platform accepts.

Your options in one place

For a quick, guided repair, use the repair page: a free 15-second preview shows the result, and full files unlock for $9/month or $29/year. For full control, use the free tools and steps on this page. For background on why MP4s break, read what the moov atom is.

Fix order that saves time

Check the player before the file. Check the copy before the original. Remux before rebuilding. Rebuild before re-encoding. Re-encode only when frames are damaged or the format is incompatible. Following this order means you always try the fastest, most lossless fix first and only escalate when you need to.

Common symptoms of a broken video and what they mean

A video that will not open at all usually has a missing or damaged header or index. A video that opens but shows the wrong duration has an index that does not match the data. A video with sound but a black picture often has a video track problem or an unsupported codec. A video that freezes at the same moment every time has a damaged region at that point. Grey or green blocks indicate damaged frames.

Each symptom suggests a different fix: rebuild the index, correct the duration, convert the codec, or cut around the damaged region. Matching the fix to the symptom avoids wasted effort.