AVI to MP4 Converter
Convert old AVI videos into modern MP4 files that play everywhere, in your browser. Your files are never uploaded to our servers. ToolkitPoint processes them on your own computer, so confidential documents stay with you.
Processed in your browser. Your files are not uploaded.
How to use AVI to MP4 Converter
- This page presets the output container to MP4.
- Add your AVI file (or several for a batch).
- Read the per-file plan: it says whether each stream is copied or re-encoded and which devices will play the result.
- Optionally change resolution, quality or audio settings, then start the conversion.
- Download the MP4 file, or all results as a ZIP.
What AVI to MP4 Converter does
Convert old AVI videos into modern MP4 files that play everywhere, in your browser.
Most media work stays in browser memory. Heavy converters lazy-load a local WebAssembly engine only after processing starts. For AVI to MP4 Converter, the operation is specifically to convert old AVI videos into modern MP4 files that play everywhere, in your browser.
Worked example
An old camcorder clip family.avi (Xvid video, MP3 audio, 640 x 480, 90MB) becomes family.mp4 with H.264 video and AAC audio, which plays on a phone, a smart TV and in web browsers. The resolution is kept; it is never enlarged.
When AVI to MP4 Converter is the right tool
- Rescuing old camera and phone videos stored as AVI.
- Making downloaded AVI files play on mobile devices.
How to verify the result
Play the beginning and end of the output, confirm duration and format, and check lip-sync or audio quality where relevant. The final AVI to MP4 Converter output should visibly match this goal: Convert old AVI videos into modern MP4 files that play everywhere, in your browser.
Important limitations
Large media jobs can be slow or run out of browser memory. Keep the tab open and use desktop software for very large or production-critical files. This matters here because AVI to MP4 Converter is designed to convert old AVI videos into modern MP4 files that play everywhere, in your browser, not to repair unrelated source problems.
A free AVI to MP4 Converter alternative
People looking for AVI to MP4 Converter often compare products such as CapCut, Kapwing, VEED. ToolkitPoint is not affiliated with those services. This page keeps convert old avi videos into modern mp4 files that play everywhere, in your browser free and available without an account; features, limits, and policies on other products can change, so compare their current product pages before choosing.
Last updated: September 27, 2026
Frequently asked questions
Why convert AVI at all?
AVI is an old container, often holding DivX, Xvid or MJPEG video that phones and browsers do not play. MP4 with H.264 plays almost everywhere.
Will the video look worse?
The video is re-encoded, which is lossy, but at the default quality the result is usually indistinguishable from the old source, and often smaller.
Can it fix the aspect ratio of old videos?
The converter keeps the source proportions and never enlarges the picture. You can choose a lower resolution to save space, but it does not stretch or crop.
Is there a size limit?
The first conversion downloads about 32 MB of processing code; videos over 250 MB are rejected because the browser must hold them in memory.
Is it private?
Yes. Your videos are processed on your computer only.