Getting the Audio Out of a Video File
A lecture, an interview, a podcast recorded on video: often the picture is incidental and only the sound is worth keeping. Extracting the audio produces a file a fraction of the size that plays on anything, and it can be listened to without a screen.
This tool pulls the audio track out of a video and saves it as M4A, which carries AAC audio. Despite the tool name, the output is M4A rather than MP3, the two are equivalent in practice, and M4A is generally the more efficient of the pair.
How to Extract Audio from Video
The only real decision is the bitrate, and speech needs far less of it than music.
- Drop the video file onto the box above. MP4, WebM, MOV, AVI and MKV are all accepted.
- Choose the bitrate. 128 kbps is plenty for lectures, interviews and podcasts; 192 or 256 kbps is worth it for music.
- Start the extraction. Longer videos take proportionally longer, since the audio has to be decoded and re-encoded.
- Download the resulting M4A file. It plays in every modern music app, phone and car system.
- If you need MP3 specifically for an old device that will not read M4A, convert the result with a desktop tool, the two formats are close cousins and the conversion is straightforward.
Why M4A Rather Than MP3
M4A is a container holding AAC audio, and AAC is the successor to MP3, it produces better sound at the same bitrate, particularly below 128 kbps. It is the format used by Apple Music, YouTube and most streaming services, and it plays natively on every phone, laptop and modern car stereo.
MP3 remains more universal in the strict sense, because a device from 2005 will play it and might not play M4A. That is the only real advantage it retains. The reason this tool produces M4A is that AAC encoding is built into the browser, while MP3 encoding is not, and the libraries that add it carry licence terms this site does not accept.
Bitrate for Different Content
What each setting produces for an hour of audio, and what it suits.
| Bitrate | Size per hour | Good for |
|---|---|---|
| 64 kbps | ~29 MB | Speech only, where size matters most |
| 96 kbps | ~43 MB | Podcasts, lectures, audiobooks |
| 128 kbps | ~58 MB | The general default, comfortable for speech |
| 192 kbps | ~86 MB | Music, live recordings |
| 256 kbps | ~115 MB | Music where quality is the priority |
For a two-hour lecture the difference between 96 and 256 kbps is around 145 MB, and there is nothing audible in it for a single voice. Match the bitrate to the content rather than defaulting to the highest option.
What Extraction Cannot Improve
The audio can only be as good as the track inside the video. If the video was compressed for streaming, its audio has already been through a lossy encoder, and re-encoding at a high bitrate stores that result more faithfully without recovering anything. Choosing 256 kbps for a video whose audio was 96 kbps produces a larger file and identical sound.
The tool also works with files on your device rather than with links. Downloading video from a streaming service is generally against its terms of use and often against copyright law, and this tool has no way to fetch a URL in any case. Use it for your own recordings and for material you are entitled to keep.