Video Converter Online
Convert videos between MP4, WEBM, MOV, MKV, AVI, GIF, MP3 audio and custom formats.
Method and limitations reviewed August 3, 2026. Browser-first, no login required.
Converts many media inputs to MP4, WebM, MOV, MKV, AVI, GIF, MP3 or a custom extension. Codec support depends on the browser FFmpeg build and available memory.
Your data is processed in your browser and not uploaded.
About this tool
What this tool does
The video converter provides explicit presets for common containers and a custom-extension option. It is designed for short browser-based jobs where keeping media local matters more than server-scale speed.
How the result is produced
- The source is processed with FFmpeg WebAssembly in a browser worker.
- Presets cover MP4, WebM, MOV, MKV, AVI, GIF and audio-only MP3 output.
- Selected quality and bitrate settings are converted into encoder options supported by each preset.
- The result is exposed as a local downloadable file after FFmpeg finishes.
Good uses
- Converting short clips for browser or editing compatibility
- Creating a GIF or extracting MP3 audio from supported video
- Testing container changes without uploading private media
How to verify the result
- Play the entire result and check audio synchronization.
- Confirm resolution, orientation and duration after conversion.
- Test the output in the exact app or platform where it will be used.
Known limitations
- A file extension does not guarantee every codec is supported inside that container.
- Long 4K clips can be impractical in a browser because memory is limited.
- Conversion speed depends heavily on device CPU and the selected codec.