Turn AVI files into WebM
Turn your AVI into a WebM. WebM is the usual choice for HTML5 video where licence-free delivery is required. 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 WebM to AVI
How to convert AVI to WebM
- 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 WebM, or add more files and do the whole set in one go.
Why convert AVI to WebM
- 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 a WebM first.
- Completely royalty free.
- Noticeably smaller than MP4 at the same visual quality.
- Video that needs a transparent background on a web page.
- AVI: no browser plays AVI, so web use always needs a conversion.
AVI compared with WebM
How the two formats differ on the things that decide whether a conversion is worth making.
| Property | AVI | WebM |
|---|---|---|
| File extension | .avi | .webm |
| Compression | Lossy or lossless | Lossy |
| Transparency | No | Yes |
| Typical file size | Depends on mode | Smaller |
| Browser support | No browser support | All current browsers |
| Introduced | 1992 | 2010 |
| Developed by | Microsoft | |
| Standard | Proprietary | Open |
Quality and what changes
WebM 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 WebM limitation to keep in mind: slower to produce than an MP4 of the same clip.
Questions about AVI to WebM
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 a WebM. 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 WebM 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.