Slimvid

Preset · AVI to MP4 · stays on device

Convert AVI to MP4 Online

Turn old camera and screen-recorder AVI files into an MP4 that phones and browsers can play.

Drop videos here, or click to browse

Up to 1GB each · MP4, MOV, WebM, MKV, AVI, WMV and 30+ more

Choose files

Processed locally in your browser. Nothing is uploaded.

Settings

Add a video and the settings for this tool appear here.

How it works

  1. 1Drop the .avi file.
  2. 2Leave the output on MP4.
  3. 3Convert and download a phone-friendly MP4.

Processed locally in your browser. Nothing is uploaded.

Processed locally in your browser. Files never leave your device. Up to 1GB — larger files go to the desktop app.

AVI is old. Players have moved on.

Camcorders, early screen recorders and a lot of scientific software still write AVI. iPhones, Chrome and Discord often refuse to play it.

AVI has no rotation metadata, so phone-adjacent footage can look sideways until we bake the rotation into the MP4. That is handled here.

Expect a transcode, not a remux. AVI codecs (MPEG-4 ASP, MJPEG, old Xvid) rarely drop straight into MP4. The hardware encoder does the work on this device.

What you get

Input
AVI
Output
H.264 MP4
Rotation
Baked in when needed

Three steps

How to convert AVI to MP4

No sign-up, no upload queue, no watermark. Everything happens on your device.

  1. 1

    Drop your file

    Drop the .avi file.

  2. 2

    Choose settings

    Leave the output on MP4.

  3. 3

    Download

    Convert and download a phone-friendly MP4.

Same job, other limits

Related size and platform pages

Convert MOV to MP4 OnlineTurn iPhone and camera MOV files into an MP4 that actually plays in browsers, Discord and slides.MOV → MP4Convert MKV to MP4 OnlineRemux a downloaded MKV into MP4 so phones, editors and chat apps will play it.MKV → MP4Convert WebM to MP4 OnlineTurn browser recordings and VP8/VP9 WebM files into MP4 for iPhone, Premiere and chat apps.WebM → MP4Convert MP4 to WebM OnlineMake a web-native WebM from an MP4 for HTML5 pages, Chrome recordings and lightweight embeds.MP4 → WebM

Keep going

Related tools

FAQ

AVI to MP4 FAQ

Desktop app

Files over 1GB? Take it to the desktop.

The browser version is perfect for everyday clips. When you need to crunch big footage or dozens of files, the desktop app does it faster on your own hardware.

Get early accessCompare web vs desktop
  • No file size limit — 4K, hour-long recordings, anything
  • Batch queues: drop a folder, apply one preset
  • Hardware-accelerated encoding (H.264 / H.265)
  • Works fully offline, same privacy guarantee