What this is for
Plenty of useful sound ends up trapped inside a video: a recorded lecture or class, a talk you filmed on your phone, your child's school performance, a song you sang at a family function, an interview, or a voice message someone sent as a video. Saving the sound on its own gives you a file that is a fraction of the size, plays in any music app, and can be listened to with the screen off. Please only extract sound from videos you made or have the right to use.
MP3 or M4A
- MP3 is the universal choice. Every phone, computer, car stereo, smart speaker and website plays it.
- M4A (AAC) is the format iPhones and Apple Music use, and the same kind of sound most phone videos already contain. It sounds slightly better than MP3 at the same size, and it is the only option that can copy the original sound without any conversion.
Choosing a bit rate
The bit rate decides how much detail is kept and how big the file is. As a guide:
| Bit rate | Good for | Size per minute |
|---|---|---|
| 128 kbps | Speech, lectures, podcasts | About 1 MB |
| 192 kbps | Music for everyday listening | About 1.4 MB |
| 256 kbps | Music on good headphones | About 1.9 MB |
| 320 kbps | The most MP3 allows | About 2.4 MB |
A higher number cannot add quality the video did not have. Phone videos usually carry sound at roughly 128 to 256 kbps, so going to 320 kbps mostly makes a larger file.
The "Original" setting: instant and lossless
Most iPhone and Android videos store their sound as AAC, which is exactly what an M4A file holds. Choose M4A and the "Original" quality, and the sound is lifted out of the video without being converted at all. It takes a moment even for an hour-long recording, and the result is identical to the sound in the video. If the video's sound turns out to be something else (Opus in many WebM files, for example), it is converted to AAC at 192 kbps instead, and the result tells you which happened.
Only need part of it?
Save the whole sound first, then cut out the part you want with the audio cutter, which can also make it a ringtone. Or trim the video first with the video trimmer. To change an existing sound file from one format to another, use the audio converter. Details stored in the video, such as where it was filmed, are not copied into the sound file.
The engine behind this tool
Video and sound are processed by FFmpeg, the open-source engine behind most of the world's video software, compiled to run inside your browser as ffmpeg.wasm. It is downloaded from this site (about 31 MB) the first time you use a video or audio tool, and your browser keeps it for next time. FFmpeg and ffmpeg.wasm are free software, licensed under the GNU General Public License version 2 or later; their source code is at github.com/ffmpegwasm/ffmpeg.wasm.