Online Video Converter
Convert video between MP4, MOV and MKV in your browser. A free online video converter that turns MKV to MP4, AVI to MP4, MOV to MP4 and more. No upload, no signup.
Drop your video here
or click to select a file
Supports MP4, MOV, MKV, WebM, AVI, FLV, WMV and more (up to 500MB on desktop, 100MB on mobile)
How It Works
1. Upload your video
Pick any video file. MP4, MKV, AVI, MOV, WebM and more all work, and it stays on your device.
2. Pick a format
Choose MP4 for the widest compatibility, or MOV or MKV.
3. Download
Save your converted video and you are done.
Popular video conversions
Supported video formats
Sondra reads MP4, MOV, MKV, AVI, WebM, FLV, WMV, M4V and 3GP files, so you can convert almost any video you have. Drop it in and pick the format you want.
For the output you can choose MP4 for the most compatible file that plays everywhere, or MOV and MKV when you need those containers. Common conversions like MKV to MP4, AVI to MP4, WebM to MP4 and MOV to MP4 are quick and keep your video looking sharp.
Convert video to MP4 and other formats, free
Sondra is a free online video converter that works entirely in your browser. Change MKV to MP4, AVI to MP4, or MOV to MP4 so your video plays on phones, TVs and social platforms. No account, and nothing is uploaded.
When the source and target already use compatible codecs, Sondra just rewraps the file, which is instant and keeps the exact same quality. Otherwise it re-encodes with H.264, the most widely supported video codec, always using a pixel format that plays everywhere. It all runs locally with FFmpeg, so your video never leaves your device.
Because the conversion happens in your browser, nothing is uploaded and there is no queue. It works on any device with a modern browser, with no signup needed.