How to fix a corrupted iPhone video
Most iPhone videos that "won't play" are not corrupted: they are still in iCloud, or the computer lacks an HEVC decoder. Check those first. A video that is genuinely broken, because the phone shut down, the camera app crashed or storage filled up during recording, usually has all its frames but no index. Rebuild that index with a five-second reference video recorded on the same iPhone with the same format, resolution, frame rate, lens and HDR setting. The FixMP4 repair tool does this in your browser, with a free preview, and never uploads your video.
Quick triage
| Symptom | Real cause | Fix |
|---|---|---|
| Photos: "error loading a higher quality version" | Original not downloaded from iCloud | Good Wi-Fi, free iCloud space, retry; check iCloud.com |
| Plays on iPhone, not on Windows | HEVC codec missing on PC | VLC, or install HEVC support; or use Most Compatible |
| Black picture with sound in an editor | HEVC or Dolby Vision unsupported by the editor | Update the editor or transcode |
| 0:00 duration everywhere, large file | Missing index | Rebuild the index (below) |
| Tiny file (a few KB) | Nothing recorded | Not repairable |
| Copy is broken, original fine | Interrupted transfer | Copy again with Keep Originals |
Our blog post iPhone video corrupted after recording explains each case in depth.
Why iPhone recordings lose their index
The Camera app writes a QuickTime MOV file: HEVC (High Efficiency) or H.264 (Most Compatible) video plus AAC audio, sometimes with extra metadata tracks. Frames are written as they are captured; the moov atom, which lists every frame's position and timing, is written at the end. A sudden shutdown from a dead battery or overheating, an app crash, a forced restart or a full storage stops the recording before that happens. Third-party apps such as streaming, filmmaking and dashcam apps are more often affected than Apple's Camera app.
Getting the original file
- Mac: Image Capture over a cable; keep originals.
- Windows: Photos app import or the DCIM folder in File Explorer. On the iPhone set Settings, Photos, Transfer to Mac or PC to Keep Originals, so the phone does not transcode during transfer.
- Third-party apps: use the app's export or the Files app.
Recording the right reference
| Setting (Settings, Camera) | Match it |
|---|---|
| Formats: High Efficiency or Most Compatible | Required |
| Record Video: resolution and fps (e.g. 4K at 60) | Required |
| Lens used (0.5x, 1x, 2x/3x/5x) | Strongly recommended |
| HDR Video (Dolby Vision) | Required |
| Action mode, Cinematic, Slo-mo, Time-lapse | Use the same mode |
| Same iPhone model and iOS version | Recommended |
| Same app (for third-party recordings) | Required |
Five seconds is plenty. See how to choose a reference file.
Rebuild the index
- Open the repair tool on a computer (large files are easier there).
- Drop the broken MOV and the reference.
- Watch the free preview. Blocks or smeared colour mean the reference does not match; record another.
- Export the full file with a subscription.
What is supported
| iPhone recording | Result |
|---|---|
| HEVC or H.264 video from Camera | Recovered |
| Dolby Vision HDR | Recovered as HEVC; HDR metadata may be simplified |
| Slo-mo and Time-lapse | Recovered as normal-speed video at the recorded frame rate |
| Cinematic mode | Recovered as normal video, no editable depth |
| ProRes and ProRes Log | Not supported |
| Spatial video | Not supported |
| Screen recordings | Usually recovered (H.264/HEVC) |
Audio only? Voice Memos are easier
If your broken recording is a Voice Memo rather than a video, you usually do not need a reference at all. See fix a corrupted Voice Memo.
Large 4K and long recordings
A minute of 4K at 60 fps HEVC can be 400 MB or more. The browser reads the file straight from disk, so size is not a problem, but make sure you have at least as much free space as the original for the export. Keep the broken original until you have checked the full export from start to finish.
Why not use an online converter?
Converters and online "repair" sites that upload your file need a readable index too, so a file without one fails there in the same way. Uploading private family videos to an unknown server is also a risk. A local index rebuild avoids both.
How the rebuild works on an iPhone MOV
The broken file still contains the HEVC or H.264 frames and the AAC audio, interleaved in chunks inside the media data. FixMP4 walks through that data, recognises where each video frame starts by its NAL unit structure, measures each AAC audio frame by parsing it, and separates the two streams. It then takes the parameter sets (resolution, profile, frame structure) from your reference video, computes timestamps and the reordering needed for B-frames, marks keyframes for seeking, and writes a fresh index. The video frames themselves are not re-encoded, so quality is identical to the original recording.
Common mistakes
- Using a reference recorded on a different iPhone model, or after changing Formats from High Efficiency to Most Compatible.
- Repairing a transcoded copy (for example one sent through a messaging app) instead of the original from the phone.
- Clearing Recently Deleted while the broken original is still in it.
Prevention
- Keep 10 GB or more free before long 4K recordings.
- Avoid recording in direct sun or while fast-charging in a hot car.
- Charge before important events; cold weather drains batteries quickly.
- Update iOS and recording apps.
- For third-party apps, stop recording before switching away.
Related guides
FixMP4 compared with other options
| Feature | FixMP4 | Desktop repair suites | untrunc (CLI) | VLC |
|---|---|---|---|---|
| Runs where | Browser, on your device | Desktop app | Command line | Desktop player |
| Keeps your file on your device | ✓ | ✓ | ✓ | ✓ |
| Nothing to install | ✓ | ✕ | ✕ | ✕ |
| Rebuilds a missing MP4/MOV index | ✓ | ✓ | ✓ | ✕ |
| Preview of your own repaired file before paying | ✓ | Trial (varies) | Free tool | n/a |
| Voice Memos / AAC without a reference | Usually | Varies | ✕ | ✕ |
| Formats beyond MP4/MOV/M4A | ✕ | ✓ | Many (FFmpeg) | Plays many |
Frequently asked questions
Why does my iPhone video not play?
Often because the original is still in iCloud or the computer lacks an HEVC decoder. If it shows 0:00 on every device and the file is large, the index is missing and can be rebuilt.
What reference video do I need for an iPhone repair?
A few seconds recorded on the same iPhone with the same format (High Efficiency or Most Compatible), resolution, frame rate, lens and HDR setting.
Can FixMP4 repair iPhone ProRes videos?
No. ProRes and spatial videos are not supported. HEVC and H.264 recordings are.
Will location and date be restored?
Not always. Metadata stored only in the lost index cannot be recovered, but the video and audio can.