.mp4.avi
How to Convert MP4 to AVI
To convert MP4 to AVI, upload your MP4 above, select AVI, and download a legacy-compatible video for older systems. This is a niche conversion — the usual reasons are ancient media players, legacy digital signage, old embedded systems, or software from the 2000s that only accepts .avi. Expect larger files and no quality benefit; convert only when a legacy target requires it.
This page is part of the Video Converter hub, which covers every video format pair JoltFile supports.
In-browser video limit: 1 GB per file
Browser-based processing — your files never leave your device
Need files over 1 GB, batch conversion, or keyboard shortcuts?
JoltFile desktop appHow to convert MP4 to AVI in 5 steps
The whole process takes under two minutes and requires no software installation or account. Your original MP4 file is never modified.
Upload your MP4 file
Drag your .mp4 file onto the converter above, or click “Browse files” to select it from your device. Files are processed locally in your browser whenever possible — nothing is uploaded to a server.
Confirm the output format is AVI
The converter defaults to MP4 → AVI on this page. If you dropped in a different file type, set the target format to AVI (.avi) using the format menu.
Adjust quality settings
Pick a resolution and quality preset. 'High' keeps the source resolution and is visually transparent; lower presets shrink the file for messaging and email.
Convert the file
Click “Convert”. JoltFile processes the file and shows a progress indicator — most video conversions finish in a few seconds.
Download your AVI file
Save the converted .avi file to your device. The original MP4 file is never modified, and temporary data is discarded automatically.
What happens to quality when converting MP4 to AVI?
Video typically re-encodes to Xvid or keeps H.264 in an AVI wrapper (compatibility varies by player). AVI predates modern streaming features, so files often grow and some players won't handle H.264-in-AVI. Audio converts to MP3 or AC3. There is no quality upside — this conversion exists purely for legacy compatibility.
When should you convert MP4 to AVI?
- Playing video on legacy DVD/divx-era hardware players
- Feeding old digital signage and kiosk systems
- Supporting embedded devices with AVI-only firmware
- Meeting legacy software import requirements
MP4 vs AVI: format comparison
| Property | MP4 | AVI |
|---|---|---|
| File extension | .mp4 | .avi |
| Full name | MPEG-4 Part 14 | Audio Video Interleave |
| Compression | Lossy container (usually H.264/H.265) | Container (usually lossy codecs) |
| MIME type | video/mp4 | video/x-msvideo |
| Introduced | 2001, by MPEG | 1992, by Microsoft |
| Best for | Sharing, streaming, and uploading video anywhere | Legacy footage archives; convert to MP4 for any modern use |
About the MP4 and AVI formats
What is MP4? (MPEG-4 Part 14)
MP4 is the most universally supported video container format, standardized by MPEG in 2001. Almost always paired with H.264 or H.265 video and AAC audio, it plays natively on every modern browser, phone, TV, and social platform.
Strengths
- Plays on virtually every device and platform
- Excellent quality-to-size ratio with H.264/H.265
- Supports subtitles, chapters, and multiple audio tracks
- Required or preferred by every major social platform
Limitations
- Lossy — re-encoding always costs quality
- Not ideal for professional editing (intra-frame codecs win there)
- H.265 variants can fail on older hardware
What is AVI? (Audio Video Interleave)
AVI is Microsoft's legacy video container from 1992. It was the dominant PC video format of the 1990s and 2000s, so vast archives of older footage exist as .avi files — often with codecs (DivX, Xvid) that modern devices no longer ship.
Strengths
- Huge legacy archive compatibility
- Simple, well-documented structure
- Supports many codecs
- Still plays in VLC and most desktop players
Limitations
- No native support in modern browsers or phones
- Large files — predates modern compression
- No native support for modern features like chapters or streaming
MP4 to AVI conversion: your questions answered
Why would anyone convert MP4 to AVI in 2026?
Legacy hardware and software: old signage players, industrial embedded systems, 2000s-era editing tools, and some car head units only understand AVI. Outside those targets, there's no reason to — MP4 is strictly better.
Will the AVI file be bigger than the MP4?
Usually yes. AVI-era codecs compress less efficiently, and the container adds overhead. Expect 20–100% larger files at equivalent quality.
Which codec should the AVI use?
Xvid is the safest choice for old hardware players. H.264-in-AVI works on PCs with VLC but defeats the purpose on legacy devices, which often can't decode it.
Is it free to convert MP4 to AVI with JoltFile?
Yes. JoltFile's free tier covers everyday MP4 to AVI conversions with no account and no watermarks. Higher file-size limits and batch processing are planned for the upcoming Pro tier.
Is my MP4 file private when I convert it?
Yes. JoltFile is designed around browser-based processing: whenever technically possible your file is converted locally on your own device and never uploaded to a server. Files that do require server processing are encrypted in transit and deleted automatically after conversion.
FAQ provided by JoltFile.