Convert AVI to MP4
Convert an AVI into an MP4 right here on the page. AVI is an older Windows video file. The practical difference is that the result opens anywhere, which AVI files do not. Your file never leaves your computer.
Need the other direction? Convert MP4 to AVI
How to convert AVI to MP4
- 1 Drop your AVI .avi file onto the page, or click to browse for it.
- 2 Set the quality, or leave the default, which keeps the file small without anything showing.
- 3 Convert. The work happens on your own machine, so how long it takes depends on your computer and the file.
- 4 Download the MP4, or add more files and do the whole set in one go.
Why convert AVI to MP4
- An AVI will not open in a browser, so anything going onto a web page, into a document or into a message has to become an MP4 first.
- Plays on effectively every device, browser and TV made this century.
- Plays without draining the battery, because devices handle it natively.
- Streaming delivery with progressive download or HLS.
- AVI: no browser plays AVI, so web use always needs a conversion.
AVI compared with MP4
How the two formats differ on the things that decide whether a conversion is worth making.
| Property | AVI | MP4 |
|---|---|---|
| File extension | .avi | .mp4 |
| Compression | Lossy or lossless | Lossy |
| Typical file size | Depends on mode | Smaller |
| Browser support | No browser support | Every browser |
| Introduced | 1992 | 2001 |
| Developed by | Microsoft | ISO/IEC MPEG |
| Standard | Proprietary | Open |
Quality and what changes
MP4 stores the same content under a different set of rules, so what matters here is compatibility rather than picture quality. Convert once from the best source you have rather than through a chain of intermediate files.
- One MP4 limitation to keep in mind: fussy about subtitle tracks and unusual audio tracks.
Questions about AVI to MP4
Is my AVI file uploaded anywhere?
No. The whole thing runs inside the browser tab you already have open. Your AVI is read straight from your own disk, converted on your machine and handed back as an MP4. Nothing is sent anywhere, nothing is stored and there is no account.
Is there a file size limit?
There is no server-side limit because no server sees the file. The real ceiling is your device memory, since the input and the output both have to fit in the tab. A few hundred megabytes is usually fine on a desktop machine and considerably less on a phone.
Can I convert several AVI files at once?
Yes. Add as many as you like and they are processed one after another, then offered as separate MP4 downloads or as a single ZIP. Speed depends on your own processor rather than on a queue.
Does the converter work offline?
Yes, after the page has loaded once. The engine is cached by the browser, so you can disconnect, reload and keep converting. That falls out of doing the work locally rather than being a separate mode you switch on.