MP4 to WebM Converter
Convert MP4 to WebM. Batch-ready, stays in your browser.
Drop files here
or click to browse · paste from clipboard
Accepts .MP4 · Up to 1,000 files
How it works
Drop your files
Drag and drop, click to browse, or paste from clipboard. Up to 1,000 files at once.
Choose settings
Adjust quality, format, and other options to match your needs.
Click Convert
Everything runs in your browser via WebAssembly. MP4 to WebM Converter happens locally — no server involved.
Download
Download files individually or grab all at once as a ZIP.
Frequently asked questions
WebM is the preferred video format for web delivery — it uses VP9 video and Opus audio, both open and patent-free. Chrome, Firefox, and most Android devices play WebM natively. If you're preparing video assets for a web application or need an open-format alternative to MP4, WebM is the target.
VP9 encoding (the video codec inside WebM) is computationally intensive — significantly slower than H.264 at equivalent quality. A 5-minute 1080p file can take 2–5 minutes in the browser. This is a VP9 limitation, not a tool limitation.
No. Safari and iOS do not support WebM playback. If you need cross-device compatibility, stay with MP4. WebM is best for web applications where you control the browser environment or are targeting Chrome/Firefox users.
Yes, but process them in smaller batches if the files are large — VP9 encoding is RAM-intensive and converting many large files simultaneously may exceed available memory.
Never. Conversion runs entirely in your browser using WebAssembly. Your files do not leave your device.