MP3 Converter
FFmpeg Online — Run FFmpegin Your Browser
Turn any video or audio file into an MP3 right in your browser: MP4, MOV, M4A, WAV, FLAC and more. Nothing is uploaded.
Convert, compress, trim, and process video & audio locally. Files never leave your device. No signup. The real FFmpeg.- 100% private — nothing is uploaded
- Free, no account
- Real FFmpeg — any command runs
MP3 Converter — tool
Loading the tool…
What this does
Turn any video or audio file into an MP3 right in your browser: MP4, MOV, M4A, WAV, FLAC and more. Nothing is uploaded. It runs the real FFmpeg, compiled to WebAssembly, right inside your browser — nothing is installed, no account is needed, and your files are never uploaded to a server.
The FFmpeg command
This is the exact command the tool runs for you. Copy it to run the same conversion with FFmpeg on your own machine.
ffmpeg -i input.mp4 -vn -c:a libmp3lame -b:a 192k output.mp3Convert any file to MP3
Add a video or an audio file and the tool saves its sound as an MP3. From a video (MP4, MOV, MKV, WebM, AVI and more) the picture is dropped and the sound track is kept. From audio (M4A, WAV, FLAC, OGG, AAC and more) the sound is re-encoded as MP3.
Because this is the real FFmpeg, it reads the same files the FFmpeg command line does. If a file has no sound track, the tool tells you instead of making an empty MP3.
Choosing a bitrate
Bitrate sets the quality and the size of the MP3. Keep the 192 kbps default for music; for speech, 96 or 128 kbps is plenty and makes much smaller files. A higher bitrate can't add quality the original file didn't have.
| Bitrate | Size per minute | Good for |
|---|---|---|
| 96 kbps | ≈ 0.7 MB | Speech, voice notes |
| 128 kbps | ≈ 1 MB | Podcasts, lectures |
| 192 kbps (default) | ≈ 1.4 MB | Music, most uses |
| 256 kbps | ≈ 1.9 MB | Music from a high-quality source |
MP3 here is constant bitrate, so size depends only on bitrate and length.
Your files stay on your device
Most online MP3 converters upload your file to their server, convert it there and send it back. This one doesn't: FFmpeg runs inside your browser tab, so the file never leaves your computer or phone and there is no upload to wait for.
Converting an MP3 to another format
To go the other way, choose another conversion in the tool, or open one of the MP3 conversions listed on this page: MP3 to WAV, OGG, M4A or FLAC.
Same commands. No limits.
Test in your browser free — run at scale on Rendi's FFmpeg API. n8n, Zapier & Make integrations.
Frequently asked
Which files can I convert to MP3?
Most video and audio files: MP4, MOV, MKV, WebM and AVI videos, and M4A, WAV, FLAC, OGG and AAC audio. It's the real FFmpeg running in your browser, so it reads the same formats the FFmpeg command line does.
Can I convert a YouTube link to MP3?
No. The tool converts files on your device and doesn't download anything from the internet. If you have the file and the right to use it, add the file instead.
Does converting to MP3 lose quality?
A little, because MP3 is a compressed format. From WAV or FLAC you get a file several times smaller with a loss most people can't hear at 192 kbps. From a file that is already compressed, like M4A or the sound in an MP4, it's a second compression step; at 192 kbps or higher the difference is hard to hear.
Is this MP3 converter free?
Yes. There is no account, no sign-up and no limit on how many files you convert. Nothing is installed either: it runs in your browser.
Is it really private?
Yes. FFmpeg runs entirely in your browser via WebAssembly. Your files are never uploaded, streamed, or seen by any server — including ours.
What's the file size limit?
Around 2 GB, and it's a browser limit rather than ours. WebAssembly can only address so much memory, so the whole job has to fit in the tab. Lightweight operations that copy streams instead of re-encoding (trimming, remuxing, stripping the audio track) work on files right up near that ceiling, because the file is read in place instead of being copied into memory. Full re-encodes need room for the input, the output, and working memory at once, so their practical ceiling is lower — lower still on phones. For anything bigger, the exact same command runs with no size limit on the Rendi API.
Does it work on my phone?
Yes. It's a web page, so it opens in Safari or Chrome on a phone the same way it does on a laptop: nothing to install, and your files still never leave the device. The layout is built for touch, and the Run button stays pinned to the bottom of the screen while you work. What changes on a phone is memory — there's much less of it, so the size limits are halved: the tool stops at files over about 1 GB, and it refuses re-encodes over 500 MB instead of letting the tab crash mid-run. Trimming, remuxing and extracting audio stay cheap, so those are the jobs a phone handles best. For a long video or a heavy encode, send the same command to the Rendi API; that works from a phone just as well.