MP3 vs WAV
MP3 and WAV are both in wide use and are chosen for different reasons. This page sets them against each other on the things that decide between them, and links to the converters for both directions — every one of which runs in your browser, with the file never uploaded.
The short answer
WAV is the recording exactly as captured and MP3 is a compressed approximation of it, so on paper WAV wins. In practice the approximation is good enough that most listeners on most equipment cannot tell them apart, and the size difference is not subtle: three minutes is about thirty megabytes as WAV and three to seven as MP3.
The choice follows from what happens next. If the audio is going to be edited, WAV is what the software wants and re-saving costs nothing. If it is going to be listened to, carried on a phone, or sent to somebody, MP3 is the format that fits and that everything plays.
The trap here is converting MP3 to WAV expecting an improvement. Editors demand WAV, so the conversion is often necessary — but it is a repackaging, not a restoration. If the plan is to edit and re-export, expect the result to be no better than the MP3 you started from, and slightly worse if the export is lossy again.
Side by side
| Property | MP3 | WAV |
|---|---|---|
| Compression | Lossy, discarded sound cannot return | None, every sample as recorded |
| Three minutes of stereo | About 3 to 7 MB | About 30 to 32 MB |
| Artist and album tags | Yes | No |
| Plays in browsers | Yes | Yes |
| Published | 1993 | 1991 |
Where they actually differ
- They treat the recording differently. One returns every sample exactly as it was given; the other discards sound its encoder judged inaudible and cannot recover it.
- For three minutes of stereo, MP3 produces the smaller file, and the gap is large enough to decide how much fits on a device.
- Only MP3 has a standard place for artist, album, and cover art. Converting to the other loses them with nowhere to put them.
- They are near contemporaries, which is why they overlap as much as they do.
What people get wrong
- Converting from the lossy one to the lossless one does not repair anything. The detail its encoder discarded is not in the file, so what you get is a larger file holding exactly the same damaged image.
- Converting between two lossy formats re-encodes an already-compressed recording, so the result is slightly worse than the input whatever quality you pick. Work from the least-processed copy you have.
- Camera settings, dates, and copyright fields do not survive the trip into the format that has nowhere to put them. If attribution matters, check the output rather than assume, because the loss is silent.
- Expect the file to change size substantially in one direction. That is the formats behaving as designed rather than a failed conversion, and it catches people who assume a conversion is roughly size-neutral.
Which to choose
- Choose MP3 when
- Choose MP3 for listening, sharing, publishing, and anywhere a size limit applies — which is nearly everywhere outside an editor.
- Choose WAV when
- Choose WAV for recording and editing, and for a master copy you will produce other formats from later.
Converting between them
Common questions
- Can I get WAV quality back from an MP3?
- No. Converting an MP3 to WAV produces a large file containing exactly what the MP3 held, which is a recording that has already had detail removed. The result is bigger, not better. Convert to WAV when a program demands one, not in the hope of recovering anything.
- Which of MP3 and WAV is better?
- Neither, in general — if one were simply better the other would have disappeared. They are good at different things, and the short answer above says which is which. The useful question is what the file has to do next: be edited, be published, be opened by somebody else, or fit inside a size limit.
- Does converting between them lose anything?
- It depends on the direction. Converting into a format that stores everything loses nothing but does not recover anything either; converting into one that discards detail loses a little each time. The table above says which of these two does which.
- Can I convert back afterwards?
- The file will convert back, but whether it comes back unchanged depends on the direction. Between two formats that store everything, a round trip is lossless. Where one of them discards detail, that detail is gone and the return journey cannot invent it.
- Can I use both?
- On a web page, often yes, and it is usually the right answer: serve the smaller modern format and list an older one as a fallback so each browser takes what it understands. For a file you are handing to a person, pick one — the one they can open.
- Which one does my software support?
- The side-by-side table above says which browsers read each, which is the part that varies most. Desktop support is harder to state in general and tends to lag browsers by years, so if the file is going to somebody else, the older and more widely read of the two is the safer choice.
- Is converting between them free?
- Yes, with no account and no limit on how many files you convert. Every converter linked from this page runs in your browser: the file is read from your device, converted by code running on it, and handed back as a download.
- Is my file uploaded?
- No. There is no conversion server here to upload it to, and no third-party service is involved. You can confirm it yourself: open your browser's developer tools, switch to the Network panel with no filter, and run a conversion — no request carries your file.