AVI to MP4 Converter
Bring old AVI videos up to date. AVI files from digital cameras, early phones, DivX and Xvid encoders or screen capture software are converted to H.264 MP4, which plays on every modern device and is usually much smaller.
- Files stay on your device
- No sign-up
- Free to use
Conversion
Quality
Processing happens on your device with FFmpeg. Keep this tab open; long or high-resolution videos can take several minutes.
How to use AVI to MP4
- Drop an AVI file onto the upload area.
- Keep Compatible to convert to H.264 and AAC, the safest choice for AVI files.
- Choose a quality level and, for large files, an optional maximum resolution.
- Select Convert to MP4 and download the converted video.
AVI to MP4 features
Handles legacy codecs
Reads AVI files using DivX, Xvid, MJPEG, DV, Cinepak and other codecs common in older files.
Modern H.264 output
Converts to the codec supported by every current phone, browser and TV.
Smaller files
H.264 is far more efficient than many older AVI codecs, so files often shrink considerably.
Audio converted too
MP3, PCM and other AVI audio formats become AAC, kept in sync.
Fast option for H.264 AVIs
If an AVI already contains H.264, it can be remuxed without quality loss.
Private
Converted entirely in your browser.
When to use AVI to MP4
- Converting home videos from early 2000s digital cameras.
- Playing DivX and Xvid films on smart TVs and phones.
- Uploading old screen recordings or game captures to modern platforms.
- Shrinking large MJPEG camera clips for storage.
- Preparing archive footage for editing software.
AVI to MP4 FAQ
Why do my AVI files not play on my phone?
AVI is an old container that often holds codecs phones and browsers do not support, such as DivX, Xvid or MJPEG. Converting to H.264 MP4 solves this.
Will converting improve the quality?
No. Conversion keeps the existing quality as closely as possible but cannot add detail lost in the original encoding.
Why is my MP4 smaller than the AVI?
Modern codecs compress far more efficiently. Camera AVI files using MJPEG store each frame as a separate JPEG and can shrink to a fraction of their size.
My AVI is interlaced. Does that matter?
Old camcorder footage is sometimes interlaced, which can show comb-like lines on motion. The picture is converted as is; a dedicated deinterlacing step in a video editor gives the best results for such footage.
What if the video has no sound after conversion?
Some AVI files use rare audio codecs. If the sound is missing, the original audio could not be decoded; try converting the file with a desktop tool such as HandBrake.
A short history of AVI
Audio Video Interleave was introduced by Microsoft in 1992 for Video for Windows. It was simple and flexible: almost any codec could be placed inside, with audio and video chunks interleaved so they could be read together. That flexibility made it the default format for PC video for well over a decade, and for early digital cameras and DivX and Xvid encoded films.
The same flexibility is now the problem. AVI predates features that modern players rely on, such as reliable support for B-frames, variable frame rates and streaming. Many files use codecs that phones, browsers and TVs never supported. A player may open the file and show only sound, or nothing at all.
Converting to H.264 inside MP4 replaces both layers with a modern equivalent. H.264 is far more efficient than MPEG-4 Part 2 codecs like DivX and Xvid and dramatically more efficient than MJPEG, so converted files are often smaller while looking the same.
If you are digitising an archive, keep the original AVI files alongside the converted MP4s. Storage is cheap, and originals may be useful if better tools for restoration or upscaling become available.