MP3 vs WAV
The size difference is about tenfold. When that trade is worth taking, when it is not, and which one to hand to someone else.
In short
WAV keeps every sample and costs about 10MB a minute. MP3 discards what you are unlikely to hear and costs about 1MB a minute at 128 kbps. Work in WAV, deliver in MP3 — and never convert MP3 to WAV expecting an improvement.
These are the two ends of the audio spectrum: one stores everything, the other stores what you will notice.
| WAV | MP3 | |
|---|---|---|
| Compression | None | Lossy |
| Size per minute | ~10 MB (CD stereo) | ~1 MB at 128 kbps |
| Quality | Exactly the source | Very close at 192 kbps+, degraded below 96 |
| Editing | Ideal — no accumulating loss | Each re-export loses more |
| Compatibility | Universal | Universal |
| Metadata / cover art | Poorly supported | Well supported |
Use WAV when
- You are recording or editing, and will export again.
- You are handing the file to someone who will work on it.
- It is going into video production, where the mix happens later.
Use MP3 when
- Someone is going to listen to it, and that is all.
- It has to be emailed, uploaded, or fit on a device.
- It needs a title, artist and cover art attached.
FLAC is usually the better lossless choice
If you want lossless and size matters at all, FLAC stores the identical waveform in roughly 40–60% of the space. WAV's advantage is that it decodes instantly and every editor accepts it — which matters while working, less so for storage.
Mistakes worth avoiding
- Archiving masters as WAV when FLAC halves the size for free.
- Editing an MP3 and re-exporting as MP3 repeatedly.
- Emailing a WAV. An hour of audio is 600MB.
Tools used in this guide
Related guides
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