AVI to MP4 Converter
Convert AVI videos to MP4 in your browser. MP4 is ideal when you need sharing, uploading, and everyday video playback, while AVI is better known for still appears in older Windows and camera exports.
- Files never uploaded
- Instant, on-device
- Free & no sign-up
Drop AVI files here, or browse
AVIMP4 · files stay on your device
up to 150 MB per file · up to 20 files per batch
How to convert AVI to MP4
- Step 01
Add your AVI file
Drop one or many AVI files onto the converter, or browse from disk. Stay within the on-device size limits shown under the drop zone — oversized files are rejected so your tab does not freeze.
- Step 02
Encode locally
Press Convert and let the in-browser media engine transmux or re-encode to MP4. Larger clips take longer because your CPU does the work.
- Step 03
Download MP4
Save the finished MP4 file when encoding completes. Multi-file jobs download together as a ZIP.
Why convert AVI to MP4
AVI shows up in older cameras and Windows archives. MP4 brings that footage into phones, browsers, and editors that abandoned AVI years ago.
When to use this tool
- You dug up legacy home videos that will not play in modern apps.
- You need to upload old footage to a platform that lists MP4 only.
- You are consolidating an archive onto contemporary devices.
Good to know
- Ancient codecs inside AVI may fail if the browser engine cannot decode them.
- Expect longer processing for hour-long tapes digitized at high bitrate.
- Compare a short sample first if the AVI uses an unusual FourCC.
- Browser limit: about 150 MB per video and up to 10m long, with at most 20 files per batch.
- Need a bigger file? For 1 GB films, long recordings, or 4K masters, use HandBrake, FFmpeg, VLC, or your editor’s export. Those tools stream from disk and handle large media far better than a browser tab.
File size limits for AVI to MP4
Browser limit: about 150 MB per video and up to 10m long, with at most 20 files per batch.
Why there is a limit
Video encoding runs in WebAssembly inside your browser. The whole clip is loaded into memory, so multi‑hundred‑MB or hour-long files often freeze tabs — limits keep encodes practical without a server.
If your file is too large
For 1 GB films, long recordings, or 4K masters, use HandBrake, FFmpeg, VLC, or your editor’s export. Those tools stream from disk and handle large media far better than a browser tab.
AVI to MP4 FAQ
Common questions about converting AVI files to MP4.
Is this AVI to MP4 converter free?
Yes. Browser Convert does not charge for AVI → MP4, add watermarks, or require an account.
Why is the first AVI to MP4 conversion slower?
The browser loads a local media engine so encoding can happen without a server. After that warm-up, subsequent AVI → MP4 jobs on the same visit are typically snappier.
Will audio stay in sync when converting AVI to MP4?
Normal clips keep audio aligned. Damaged sources or unusual codecs can fail to decode — try a short sample if a long archive misbehaves.
Is AVI to MP4 conversion private on Browser Convert?
Yes. Your AVI video is processed in the browser. We do not upload the file to convert it, which is the main difference from typical online converters.
Are there file size limits for AVI to MP4?
Yes. Browser Convert accepts about 150 MB per video and clips up to 10m, with up to 20 files queued at once. Video encoding runs in WebAssembly inside your browser. The whole clip is loaded into memory, so multi‑hundred‑MB or hour-long files often freeze tabs — limits keep encodes practical without a server. If your file is larger, For 1 GB films, long recordings, or 4K masters, use HandBrake, FFmpeg, VLC, or your editor’s export. Those tools stream from disk and handle large media far better than a browser tab.
Can I convert several AVI files to MP4 at once?
Yes. Queue up to 20 AVI files and convert them in one pass. When finished, download the batch as a ZIP. Very large batches may need to be split so your browser stays responsive.