Free Media Converter — MP4, WebM, MOV, MP3, GIF (Browser, ffmpeg.wasm)

How to convert video and audio formats in your browser

Drop your file. Drag and drop any video or audio file. First use loads ffmpeg.wasm (~25 MB, cached after).
Pick output format. Select MP4 (most compatible), WebM (smallest, modern web), MOV (Apple), or audio MP3/AAC/OGG/WAV.
Set quality / bitrate. Pick a video bitrate (1 Mbps low / 4 Mbps standard / 8 Mbps HD) or audio bitrate (128 / 192 / 320 kbps).
Convert and download. Click Convert. Processing time scales with file size — typically 0.5–2× real-time.

Convert iPhone MOV to MP4 for sharing on Windows

Re-encode a large MKV to WebM for web embedding

Convert AAC podcast files to MP3 for legacy players

Extract MP3 from a video file (or use the Audio Extractor)

Convert WAV recordings to OGG for smaller storage

Are my files uploaded?

No. Conversion runs entirely in your browser via ffmpeg.wasm. Files never leave your device.

What formats are supported?

Anything ffmpeg supports: MP4, WebM, MOV, AVI, MKV, FLV, 3GP for video; MP3, AAC, M4A, OGG, WAV, FLAC, OPUS for audio.

How big a file can it handle?

No hard limit, but >2 GB files may run out of browser memory on weaker devices.

Why is conversion slow?

ffmpeg.wasm runs at 30–70% of native ffmpeg speed because it uses WebAssembly. For huge files, use desktop ffmpeg.

Will quality drop?

Lossy → lossy re-encoding always loses some quality. Pick high bitrate to minimize loss.

Does it work on mobile?

Yes on modern iPhones (iOS 16+) and Android with 4 GB+ RAM. Older devices may run out of memory.

More free, in-browser tools from the Video & Audio set — every one runs locally, with no sign-up and no upload.