MP4 to M4A

How to save the sound from a video

1. Choose up to 3 videos, MP4, M4V, MOV, WebM or MKV, each up to 25 MB and 30 minutes long.
2. Leave M4A selected, or choose WAV for uncompressed sound.
3. Press Save the sound, then download each file, or all of them together as a ZIP: holiday-clip.mp4 becomes holiday-clip.m4a.

When it helps

A recorded talk, a lecture or a video message is often easier to keep as sound alone. The file is smaller, it plays with the phone’s screen off, and it goes into a music or podcast app. The picture is left out, and the sound is saved as its own file.

M4A or WAV

• M4A (AAC): when the video’s sound is already AAC, as in most MP4s and phone videos, it’s copied as it is. That’s quick, and nothing is lost. Other sound, such as a WebM’s Opus, is converted to AAC at 128 kbit/s.
• WAV: uncompressed, for editing apps that ask for it. It’s large, about 10 MB a minute, so WAV files here can be up to 10 minutes long.
• What you get: the whole of the sound, from start to end. The note under each result shows its length and says whether the sound was copied.

Why there’s no MP3

Browsers can’t make MP3 files themselves. The add-on MP3 encoders available for browsers are built on LAME, and its license, the LGPL, isn’t one this site uses in its tools. M4A does the same job: it plays on iPhones, Android phones, Macs and Windows PCs.

Which browsers work

Copying AAC sound into an M4A works in current Chrome, Edge, Firefox and Safari. Anything that converts the sound uses your browser’s own encoder. Chrome and Edge make AAC; Firefox can’t, so choose WAV there for a video whose sound isn’t AAC; Safari needs version 26 or later to convert sound.

Good to know

Your videos stay on your device: the sound is taken out in your browser, and nothing is uploaded. A video with no sound gets a message instead of an empty file. To cut the sound down afterwards, use Trim Audio; to change a sound file’s format, use the Audio Converter. To keep the video and drop its sound instead, use Mute Video.