Mediamorphy is a free online converter that runs entirely inside your web browser. It's built on ffmpeg compiled to WebAssembly, so the same engine that powers professional video tools works right on this page — your files stay on your computer from start to finish. That makes it fast for small and medium files, and completely private: there are no uploads, no accounts, and no waiting in a queue.
Convert between popular video formats like MP4, WebM, AVI, MOV and MKV, turn a clip into an animated GIF, or extract and convert audio to MP3, WAV, OGG, M4A and FLAC. You can resize video, adjust quality with a simple slider, change the frame rate, mute the audio track, tune volume and bitrate, or trim to just the part you need.
No. Conversion happens locally in your browser using WebAssembly. Your file is never sent to us or anyone else, which is why it also works if you go offline after the page has loaded.
Yes. It's free to use with no sign-up. The site is supported by unobtrusive ads so we can keep it running.
Video output: MP4, WebM, AVI, MOV, MKV and GIF. Audio output: MP3, WAV, OGG, M4A and FLAC. Most common input formats are accepted, and you can convert a video directly into an audio-only file to extract its soundtrack.
There's no fixed limit, but because everything runs in your browser the whole file is loaded into memory, and the WebAssembly engine can address at most about 2 GB. In practice it works best for files up to roughly 1 GB; much larger files may fail to convert on many devices, so a desktop app is a better choice for those. The first conversion also downloads the converter (about 30 MB), which your browser then caches for next time.
Browser-based conversion is single-threaded and limited by available memory. Closing other tabs, using a desktop browser, or trimming the file first can help. Some unusual or DRM-protected inputs may not be supported.