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AVI to MP4 (H.264) - Online Video Converter
Convert AVI to MP4 (H.264) online. Private, client-side - no uploadrequired. Batch conversion, quality presets, codec control.
Convert AVI to MP4 (H.264)
Drop AVI video here or click to select
AVI
MP4 (H.264) (H.264 / AAC)
About AVI to MP4 (H.264)
AVI wraps aging codecs such as DivX, so MP4 moves the picture to H.264 with AAC sound.
Why convert AVI to MP4 (H.264)?
- Smaller files with MP4 lossy compression.
- Keep animation and transparency where supported.
- Private, no upload - runs in your browser.
AVI vs MP4 (H.264)
| Animation | Yes | Yes |
|---|---|---|
| Transparency | No | No |
| Compression | lossy | lossy |
| Typical use | AVI is Microsoft's 1992 RIFF container, often holding DivX or DV video. | MP4 pairs H.264 video with AAC audio in the ISO base media container. |
When not to convert AVI to MP4 (H.264)
- Skip MP4 for archival masters: lossy compression discards detail, so keep the AVI original.
- Keep a master copy: repeated exports stack small losses, so archive AVI before batch MP4 shares.
Limits
Starting point: AVI - AVI is Microsoft's 1992 RIFF container, often holding DivX or DV video. Old codecs inside may need transcoding before modern players open them. H.264 has no alpha channel, so transparency is dropped. Encode MP4 (H.264 / AAC) from AVI at a bitrate near the source, and confirm the audio track before converting.
How conversion works
Conversion runs entirely in your browser with FFmpeg WASM. Files never leave your device.
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FAQ
How do I convert AVI to MP4 (H.264)?
Drop your AVI file onto this page, choose quality and codec settings, then click Convert. The result downloads as MP4 (H.264) instantly. All processing runs in your browser.
What codec is used for MP4 (H.264)?
The default codec for MP4 (H.264) is H.264 / AAC. You can change the video and audio codec in Advanced mode.
Why does AVI to MP4 take a while?
Old codecs like DivX must fully decode before H.264 re-encodes.
Does AVI to MP4 keep audio?
Yes; MP3 or PCM tracks re-encode to AAC by default.
How do you store my files?
We do not store any processed videos. All conversion happens entirely in your browser using FFmpeg WASM.