Video Converter

Convert MP4 ↔ WebM in your browser - private, no upload.

Drop video files here or click to browseWebM, MP4, MOV, AVI, MKV

About this tool

Which video formats does it convert between?
MP4 (H.264) to WebM (VP8/VP9), and WebM to MP4. These are the two formats needed for universal browser video support.
Is video processing done in the browser?
Yes. The converter uses FFmpeg compiled to WebAssembly. Your video files never leave your machine.
How long does conversion take?
Conversion is CPU-bound and depends on video length and resolution. A 1080p 5-minute video takes roughly 2–5 minutes in the browser.
Is there a file size or length limit?
No enforced limit, but very large files (1 GB+) may exhaust browser memory. For large files, a desktop tool like Handbrake will be more reliable.

Related tools

Caffeine Clock

When will your coffee actually wear off?

☕

Caffeine Clock

When will your coffee actually wear off?

Open →

Character Counter

Count characters, words, sentences, paragraphs, and estimate reading time.

#

Character Counter

Count characters, words, sentences, paragraphs, and estimate reading time.

Open →

Clipboard Manager

Save, search, and organize text clips in your browser.

📋

Clipboard Manager

Save, search, and organize text clips in your browser.

Open →

Decision Flow

Build a yes/no troubleshooting tree and share it as a link.

🌿

Decision Flow

Build a yes/no troubleshooting tree and share it as a link.

Open →
View all tools →