Convert AVI to MP4 — Free Online Converter
Convert AVI files to MP4 format instantly. Free online converter with no watermark. Compatible with all devices and platforms.
Conversion settings — add a file to adjust
About AVI files
AVI is a Microsoft container from the early 1990s. Old digital cameras, webcams and home video archives often use it, frequently with older codecs such as MPEG-4 Part 2 (DivX or Xvid) or Motion JPEG.
AVI files tend to be large and many modern phones, browsers and editors refuse them. Converting to MP4 gives you a smaller file in H.264 that plays almost everywhere.
How we convert AVI to MP4
- Always re-encoded
- AVI is not in our copy-only set, so every AVI is re-encoded. This also means the old codec inside is replaced by a modern one.
- Video
- H.264 High profile, CRF 23, preset medium, 8-bit 4:2:0 color for wide player support.
- Audio
- AAC at 192 kbps.
- Frame size
- Kept from the source. Odd widths or heights are padded by one pixel, because H.264 needs even numbers.
Common problems and fixes
The converter says the AVI is corrupt.
Old AVI files from failing drives or interrupted captures are often truncated. Try another copy of the file, or copy it again from the original disc or card.
The MP4 looks soft compared to the AVI.
Pick the High preset. It encodes at CRF 18, which keeps more detail at the cost of a larger file.
The converted video is still large.
Pick 720p or the Low preset. Old AVI captures are often in low resolution already, so check the source size first.
About AVI to MP4 Conversion
AVI (Audio Video Interleave) was once the dominant video format on Windows computers, but today's devices and platforms prefer the more efficient MP4 format. Converting AVI to MP4 modernizes your video collection, dramatically reduces file sizes, and ensures compatibility with smartphones, tablets, smart TVs, and streaming platforms.
Our AVI to MP4 converter uses advanced encoding to transform your legacy AVI files into modern, web-ready MP4 videos. The process preserves your video's visual quality while taking advantage of MP4's superior compression technology. Most conversions achieve 40-60% file size reduction without visible quality loss.
Why Convert AVI to MP4?
AVI files served Windows users well for decades, but the format shows its age when compared to modern alternatives. AVI lacks native support for streaming, often contains outdated codecs that modern devices can't decode, and produces unnecessarily large files. Converting to MP4 solves all these problems.
MP4's H.264 codec delivers the same visual quality as AVI's older codecs at a fraction of the file size. A 2GB AVI file might become an 800MB MP4 with identical quality. This compression efficiency means faster uploads, less storage consumption, and smoother playback on mobile networks.
Modern platforms overwhelmingly prefer MP4. YouTube, Vimeo, Facebook, and Instagram all recommend MP4 uploads. Smart TVs and streaming devices like Roku and Fire TV handle MP4 natively. Even Windows 11 plays MP4 more efficiently than AVI.