What you should know
AVI to MP4 modernises an old video without changing its content. AVI files accumulated since the 2000s mostly contain DivX, Xvid or MPEG-4 Part 2, which recent devices increasingly refuse.
Re-encoding is therefore the rule, with a clear benefit: at comparable visual quality, MP4 is often two to three times lighter than an old AVI.
Strengths
- Makes otherwise inaccessible videos readable on current devices
- Greatly reduces size at comparable quality
- Enables streaming playback on the web
- Opens the door to editing in modern software
Limitations to know
- Mandatory re-encoding, with loss on an already compressed source
- AVI files with exotic codecs may fail
- Multiple tracks and old subtitles are poorly handled
- Output quality cannot exceed the source
When to use it
Convert your AVI archives when you need to watch them on a recent device, share them or edit them. Keep the original AVI if you are only archiving and disk space is not an issue.
Quality, size and compatibility
Start from the best available copy and choose a reasonable bitrate: aiming too low produces blocks in fast motion, too high inflates the file with no visible benefit.
Frequently asked questions
- Can every AVI be converted?
- The vast majority, yes. Failures involve very rare codecs or damaged files that even FFmpeg cannot fully decode.
- Does conversion improve the quality of an old AVI?
- No: it only preserves it as well as possible. Re-encoding repairs neither noise, nor blur, nor artefacts already present in the source.