Free browser tool
Bring an AVI up to date
Drop an AVI in and get an MP4 that plays on a phone, in a browser and in every editor. It converts in this tab.
- No sign up
- Nothing uploaded
- No queue
- Up to 300 MB a file
Drop a AVI in
Drag a file onto this panel or open one. It is converted to MP4 in this tab, on your own machine, and never uploaded.
Why an AVI has to be re-encoded
An AVI is a container from 1992, and what is usually inside it is DivX or Xvid. An MP4 cannot hold either. So unlike a MOV, which is normally rewrapped in a second, an AVI is decoded frame by frame and encoded again as H.264 with its audio re-encoded to AAC.
That takes about as long as the clip itself on a current laptop, because the encoder is WebAssembly running on one thread. A three minute dash cam clip is a few minutes. An hour of footage is better converted on your machine with ffmpeg or Handbrake.
The file usually gets smaller
H.264 is two codec generations ahead of what your AVI is carrying, so the same picture needs roughly half the bits at the same quality. CRF 23 is the setting used here, which is the one people use for delivery rather than for archiving.
Where AVI files come from
Dash cams, old camcorders, security recorders, capture software from the DVD era, and downloads from the 2000s. They play in VLC and almost nowhere else: no phone decodes DivX, no browser plays an AVI, and most editors will not import one.
It stays on your machine
Old AVI files are usually personal footage, and most converters that rank for this phrase upload yours to a server. This page runs ffmpeg in the tab, so the file is converted on your own processor and never sent anywhere.
How it works
Converting in 3 steps
- Drop the AVI inA dash cam clip, an old camcorder file, a DivX download, a capture from screen recording software from the DVD era.
- ConvertThe video is re-encoded to H.264 and the audio to AAC, because an AVI almost never holds either already.
- DownloadThe MP4 is usually smaller than the AVI it came from, and it plays everywhere the AVI did not.
What it does
Free, and still worth using
Play it on a phone at last
AVI is a container from 1992, usually holding DivX or Xvid. No phone plays it and no browser plays it. H.264 in an MP4 plays on everything made this century.
Usually come out smaller
DivX and Xvid are two codec generations behind H.264, so re-encoding at CRF 23 typically lands at half the size with no visible difference.
Edit it afterwards
Premiere, Resolve, Final Cut and every browser editor take H.264 MP4 without arguing. Most of them will not import an AVI at all.
Convert it without sending it anywhere
Old AVI files are usually personal footage. This page converts yours in the tab, on your own processor, and uploads nothing.
On a Mac, the editing is already done
Prequel records your screen at its full resolution, then opens an editor with the zooms already placed, your camera framed and a background applied. Export one MP4 at up to 4K.
No credit card required
- Zooms placed on every click
- Camera shaped, sized and framed
- Background, padding and shadow
- Microphone and system on separate gains
- Cursor smoothed and resized
More tools
The rest of them
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Any video in, an MP3 out, converted in the tab rather than on a server.
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Free MP4 to MP3 converter
An MP4 in, the audio out as an MP3, converted in the tab.
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Free MOV to MP4 converter
QuickTime in, MP4 out, rewrapped rather than re-encoded wherever it can be.
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Free MOV to MP3 converter
A QuickTime recording in, its audio out as an MP3.
FAQ
Codecs, size and how long it takes
Why does an AVI take longer to convert than a MOV?
Because it has to be re-encoded rather than rewrapped. An AVI holds DivX or Xvid, which an MP4 cannot carry, so every frame is decoded and encoded again as H.264. A MOV usually already holds H.264 and is just put in a new box.
Will the MP4 look worse than the AVI?
Barely, and often better per megabyte. It is re-encoded at CRF 23, a delivery-quality setting, and H.264 is two generations ahead of the codec your AVI is in. A second encode always costs something; at this setting it is hard to see.
Why is the MP4 smaller?
H.264 compresses far better than DivX or Xvid at the same quality, so the same picture needs fewer bits. Halving the size is normal.
How long will it take?
Roughly the length of the clip on a current laptop, sometimes longer, because the encoder is WebAssembly on a single thread. A three minute dash cam clip is a few minutes; an hour-long file is better converted on your machine.
Is my file uploaded?
No. ffmpeg runs in this tab and the AVI never leaves your computer. There is no queue and no link waiting in an inbox.
What size can I convert?
Up to about 300 MB. The AVI, the MP4 and the encoder share the tab's memory, and that is where a long transcode starts failing part way through.
My AVI will not open. What now?
A few AVI files hold codecs this build does not carry, usually something proprietary from a camera. VLC will play almost anything and can export an MP4, and the file stays on your machine either way.
Does the audio survive?
Yes. Whatever the AVI holds, usually MP3 or AC-3, is re-encoded to AAC at 160 kbps inside the MP4.