Video Format Converter
Convert videos between MP4, WebM, MOV, AVI, and MKV. Runs locally in your browser — no uploads.
Free Video Format Converter — Convert Videos Online
This tool converts video files between formats directly in your browser. Select your target format (MP4, WebM, MOV, AVI, or MKV) and quality level, then download the converted file. No software to install, no server uploads, and no watermarks.
MP4 and MOV use H.264 video with AAC audio. WebM uses VP9 video with Opus audio. AVI and MKV use H.264 video with AAC audio. Quality is controlled via CRF (Constant Rate Factor) values.
Features
- Five output formats — MP4, WebM, MOV, AVI, and MKV.
- Quality presets — High, Medium, or Low quality for each format.
- Automatic codec selection — the correct video and audio codecs are chosen based on the output format.
- Local processing — your video never leaves your device.
- Wide input support — accepts any video format as input.
How to Convert a Video
- Click the upload area or drag a video file into it.
- Select the output format: MP4, WebM, MOV, AVI, or MKV.
- Choose the quality level: High, Medium, or Low.
- Click Convert Video. The first use downloads the video processor (~31MB, cached afterwards).
- Download the converted file.
Privacy
Your video is processed entirely in your browser using WebAssembly. No video data or metadata is sent to any server. The converted file exists only in your browser memory until you download it or close the page.
Related Tools
- Video Compressor — reduce video file size online.
- Video Trimmer — cut and trim video clips in your browser.
- Video to GIF Converter — convert video to animated GIF.
Frequently Asked Questions
Is this tool free?
Yes. It is completely free with no file size limits and no signup required.
Does my video get uploaded?
No. Your video stays on your device. All conversion happens locally in your browser.
Which format should I choose?
MP4 is the most widely compatible format and works on all devices. WebM is ideal for web content and smaller file sizes. MOV is preferred for Apple devices. AVI and MKV are good for archival purposes.
What codecs are used?
MP4, MOV, AVI, and MKV use H.264 video with AAC audio. WebM uses VP9 video with Opus audio.
Why is conversion slow?
Video re-encoding is CPU-intensive. WebAssembly runs at near-native speed but converting a full video takes time. WebM conversion is typically slower than MP4.
Can I convert audio-only files?
This tool is designed for video files. For audio extraction, use the Video to MP3 Converter.