Corrupted Video Repair
Rebuild a broken, unplayable MP4 or MOV.
Runs entirely in your browser — nothing you enter is uploaded, logged, or tracked.
When a recording is interrupted — the camera dies, the phone crashes, the card is pulled — the file often loses its “index” (the MP4 moov atom) and becomes an unplayable blob even though the actual footage is still inside it. This tool rebuilds that index using a healthy reference clip recorded on the same device and settings, then writes out a fixed, full-resolution file. It runs entirely in your browser; the video never leaves your device.
Diagnostic
✓ Repaired
Also export a smaller version (optional)
Re-encodes the repaired video to a smaller file (the full-resolution download above is always lossless and unchanged). Uses your browser's encoder — speed and format depend on the browser.
Frequently asked questions
What corruption does this fix?
The common, recoverable kind: a video that won’t open because its index/header (the MP4 “moov” atom) is missing or truncated — typically when a recording was cut off mid-capture. The footage (“mdat”) must still be intact.
Why do I need a second, working video?
A reference clip from the same camera and settings carries the codec parameters and track layout the broken file lost. The tool copies that structure to rebuild the broken file’s index. This is the same technique as the open-source tool “untrunc”.
Is my video uploaded?
No. Both files are read and rebuilt entirely in your browser; nothing is sent to a server.
What if it can’t fix my file?
It shows an honest diagnostic of what it found in both files instead of producing a broken output. Some corruption (a damaged mdat, overwritten bytes, an unsupported codec) can’t be recovered this way.
What formats are supported?
MP4 and MOV (ISO base-media files) with H.264/H.265 video and AAC audio — what almost every phone and camera records.