FileFix vs MP4Box for corrupted MP4 repair.
Try MP4Box first when it can import the damaged file and write a clean container. In our testing on real-world corrupted videos, FileFix fully repaired about half; MP4Box remux more often produced a partial result than a full repair.
Try FileFix freeWhat the test found
| Approach | Full repair | Partial repair | Failed repair |
|---|---|---|---|
| FileFix | over half | almost none | about a third |
| MP4Box remux | fewer than 1 in 10 | about a third | over half |
Source: our test of real corrupted videos, Jul 29, 2026. Each cell is the share of test files fully repaired, partially repaired, or not repaired, rounded into plain words.
Try the free tools first
Import into a new MP4 container
MP4Box -add broken.mp4 -new repaired.mp4When the free tool is the right answer
Try the free option when
- Use MP4Box when it can parse the input and the job is to place readable tracks into a new MP4 container.
- It is free and runs locally on your computer.
Try FileFix when
- Try FileFix when MP4Box cannot import the damaged file or when you want a free watermarked preview before deciding whether to pay.
Neither option can rebuild footage that was never written.
Repair guides
Questions
Yes. If MP4Box can read the tracks, writing them into a new container is a useful free first step.
No. The command imports readable tracks into a new MP4 container rather than asking you to choose new video and audio codecs.
See what's recoverable.
Preview the repaired video before you decide.