Article
How to Extract Audio From a Video (MP3, M4A, OGG or WAV — and What Bitrate)
Extracting audio is easy; format and bitrate are where quality is lost. The one rule that matters, and when MP3, M4A, OGG or WAV is the right choice.
You have a lecture recording, an interview, a podcast episode you filmed, or a track you want off a video. You need the audio and none of the picture.
The extraction itself is trivial. The two decisions that follow — which format and which bitrate — are where most people quietly throw away quality, or waste a large amount of space for none.
1. The rule that matters most
You cannot add quality that was never there.
The audio inside your video is already compressed. A typical MP4 carries AAC at somewhere between 96 and 256 kbps. If you extract that to a 320 kbps MP3, you do not get 320 kbps of quality — you get the original, slightly degraded by a second round of lossy compression, in a file two or three times larger than it needed to be.
Extracting at a bitrate above the source is pure waste. When in doubt, match roughly what the source has, or go one step below it.
2. Choosing a format
| Format | Codec | Use it when |
|---|---|---|
| MP3 | MP3 | You want it to play on absolutely anything — car stereos, old players, cheap hardware |
| M4A | AAC | Apple devices, or when you want better quality per byte than MP3 |
| OGG | Opus | Best quality per byte of the four; web and modern apps |
| WAV | PCM | Uncompressed. Feeding the audio into an editor |
A detail worth knowing: most MP4 files already contain AAC audio. Extracting to M4A therefore keeps the same codec family, which means less degradation than converting to MP3. If universal compatibility is not your priority, M4A is technically the better choice.
MP3 remains the default recommendation anyway, for one unglamorous reason: it plays everywhere, and “works on the thing my dad has in his car” beats a marginal quality gain in most real situations.
Opus is genuinely the most efficient of the four — 96 kbps Opus is comparable to 128 kbps MP3 — but player support is patchier outside browsers and modern apps.
WAV is uncompressed and enormous: roughly 10 MB per minute in stereo. It is the right answer only when the audio is going into an editor for further work, where you do not want a lossy generation before you have even started.
3. Choosing a bitrate
| Content | Bitrate | Notes |
|---|---|---|
| Speech, lecture, interview | 96–128 kbps | Transparent for voice. Files stay small |
| Podcast with music beds | 128–192 kbps | Safe middle ground |
| Music, general listening | 192 kbps | Transparent on almost all equipment |
| Music, archiving | 256–320 kbps | Only if you may re-encode later |
192 kbps is the right default for almost everyone. Above that, the returns are small enough that most listeners on most equipment cannot identify the difference in a blind test — while the file keeps growing.
For speech specifically, 128 kbps is genuinely transparent, and a two-hour lecture at 128 kbps is around 115 MB instead of 172 MB at 192.
4. Extracting audio, step by step
Our MP4 to MP3 converter runs entirely in your browser, which matters more here than for most conversions — recordings of meetings, interviews and lectures are often things you should not be uploading to a stranger’s server at all:
- Drop your video in. MP4, MOV, MKV, WebM — or an audio file if you just want to change format.
- Check the source details. Codec, channels, sample rate and the source bitrate are read locally and shown, so you know what you are working from before choosing a target.
- Pick a format. MP3 unless you have a reason otherwise.
- Pick a bitrate. 192 kbps for music, 128 for speech.
- Extract, preview in the player, and download.
Because nothing is uploaded, a two-hour recording is limited only by your own machine — which is exactly the case where server-based converters cap you.
5. Common questions
Will extracting lose quality? Slightly. The audio was already compressed, and re-encoding to another lossy format compresses it a second time. At 192 kbps and above it is rarely audible. Choose WAV to avoid a second lossy pass entirely.
Should I always pick 320 kbps to be safe? No, and this is the most common mistake. If the source is 128 kbps AAC, extracting at 320 kbps MP3 produces a file roughly two and a half times larger with no quality benefit whatsoever. Match the source or go slightly below.
Why does MP3 take a moment the first time? Browsers do not ship an MP3 encoder — it is the one common format WebCodecs does not cover. The LAME encoder loads as a small WebAssembly module (around 310 KB) the first time you choose MP3, and only then.
My video has no audio track. What now? Then there is nothing to extract. Some screen recordings capture no system audio unless it was explicitly enabled, which is the usual cause.
Can I extract just part of the audio? Trim the video first with our video trimmer, then extract from the trimmed clip.
Is my file uploaded anywhere? No. Decoding and encoding both run on your own device, which is why there is no size limit.
Related guides
- Trim a video before extracting
- Turn an audio track and a cover image into a video — the reverse direction, for YouTube or podcast platforms
- Compress a video to a specific size