Copy or convert
Most MP4 and MOV videos, including phone recordings, store their sound as AAC. Saving it as M4A, which is AAC in an audio container, can copy the stream as it is: instant and with no quality loss. Any other format means decoding and encoding the audio, which is still quick but is a conversion.
Converting a lossy AAC track to a lossless format like WAV or FLAC does not bring back lost detail. It only makes the file larger. Choose WAV or FLAC when an editing app needs it.
Which format
| Format | Type | Best for |
|---|---|---|
| MP3 | Lossy | Plays everywhere, music players, car stereos |
| M4A (AAC) | Lossy | Apple devices, often a lossless copy from MP4 |
| WAV | Uncompressed | Editing software, about 10 MB per minute in CD quality stereo |
| FLAC | Lossless compressed | Archiving a lossless source, smaller than WAV |
| OGG (Vorbis) | Lossy | Games, some web and Android uses |
| Opus | Lossy | Speech at low bitrates, voice notes |
Bitrates that make sense
- 320 kbps MP3: the maximum; useful only when the source is high quality music.
- 192 kbps: a good default for music.
- 128 kbps: fine for most listening, podcasts and lectures.
- 96 kbps or less: speech and voice notes, especially with Opus.
A higher bitrate cannot exceed the quality of the source. If a phone video's audio is AAC at 128 kbps, a 320 kbps MP3 of it will be larger without sounding better.
After extracting
Audio CutterCut the part you want, add fades, and save it as MP3 or an iPhone ringtone.Reduce Background NoiseLower steady hiss and hum in a lecture or interview.Audio ConverterChange the sample rate, channels or format of the extracted file.For more audio work, such as EQ, batch conversion or longer editing, our sister site Aback Audio has a full set of browser-based audio tools.
Common problems
- The audio is quiet. Phone videos recorded at a distance often are. Normalise the loudness after extracting, rather than pushing the bitrate higher.
- There is background music under a voice. A basic noise filter will not remove music. The AI Vocal Remover separates voice and music when you need only one of them.
- The file will not play in an old car stereo. Use MP3 at 44.1 kHz stereo, the most widely supported combination.
- You only need part of it. Cut the section afterwards rather than extracting the whole file again.
Questions
How do I convert MP4 to MP3?
Open Extract Audio, drop in the MP4, choose MP3 and a bitrate (192 kbps is a good default), and download. It runs in your browser.
Is extracting audio lossless?
It can be. Choosing M4A for a video with AAC audio copies the stream exactly. Other formats convert the audio, which is near transparent at sensible bitrates.
What if the video has no sound?
Some videos have no audio stream at all, such as many screen recordings. The tool will tell you there is no audio to extract.
Can I extract audio from a video with several audio tracks?
The first audio track is extracted, which is usually the main language. Video Info lists every track in the file.
Is the video uploaded?
No. Extraction runs in your browser and the file never leaves your device.