Convert WAV to MP3
Drop a WAV and get it back as an MP3, which every phone, car, and music app plays, at about a seventh of the size. Pick a bitrate, keep the whole file or only part of it, and the size of the MP3 is shown before you download it.
Play the sound to a moment, then press Set from player to use that time as the start or the end. Times can be typed too.
The result appears here once a file is open.
How to use it#
- Drop a WAV onto the box above, or click it to choose one.
- Pick a bitrate. 192 kbps suits most music, and 128 kbps is plenty for speech.
- To keep only part of it, set the start and end, typed or taken from the player with Set from player.
- Play the MP3 in the preview, then download it.
Why a WAV is so large, and what the MP3 keeps#
A WAV holds every sample the recorder took, uncompressed. At CD quality, 44,100 samples a second in 16 bits on two channels, that comes to about 10 MB a minute, so a four-minute song is 40 MB and an hour of a recorded meeting is 600 MB. That is too big for most email and slow to send anywhere.
An MP3 leaves out the parts of the sound the ear is poorest at hearing, such as a quiet sound just after a loud one. At 192 kbps a minute takes about 1.4 MB, a seventh of the WAV, and for most music most listeners cannot tell the two apart. Since a WAV has lost nothing, it is the best thing to make an MP3 from: the MP3 encoder is the only step that leaves anything out.
Choosing a bitrate#
128 kbps is plenty for speech, such as a lecture, an interview, or a voice note, at about 1 MB a minute. 192 kbps is the default and suits music for most listeners. 256 and 320 kbps are for music you will listen to closely or keep, at about 1.9 and 2.4 MB a minute. Even 320 kbps is under a quarter the size of the WAV.
Keep the WAV if you will edit the sound again. Every time an MP3 is opened in an editor and saved as MP3 again it loses a little more, while a WAV can be edited and saved as often as you like. Make the MP3 last, as the copy you send or play.
High sample rates, 24-bit, and surround#
Studio recordings and some field recorders save WAV at 24 or 32 bits, and at 88.2 or 96 kHz. An MP3 holds up to 48 kHz, so a recording above that is brought down to 44.1 or 48 kHz on the way in, which removes only sound above what people can hear. The extra bits make no difference to an MP3 either way.
An MP3 holds two channels at most, so a WAV with more, such as 5.1 surround or a multitrack recording, is mixed down to stereo. A mono recording stays mono. An MP3's size comes from its bitrate rather than its channels, so for a mono voice recording 128 kbps is plenty and keeps the file small.
Frequently asked questions#
Does converting WAV to MP3 lose quality?
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Some, because an MP3 leaves out detail to be small, but at 192 kbps or more it is very hard to hear for most music, and at 128 kbps for speech. If you might edit the sound later, keep the WAV as well and edit that.
Which bitrate should I pick?
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192 kbps for most music, 128 kbps for speech, and 256 or 320 kbps for music you want at its best. The size of the MP3 shows beside the result, so you can try two settings and compare.
How much smaller is the MP3?
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About seven times smaller at 192 kbps for a CD-quality WAV, and eleven times at 128 kbps. A 40 MB song becomes about 6 MB. The page shows the exact size and how much smaller it is once the MP3 is made.
Can I convert only part of the WAV?
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Yes. Set the start and the end, typed in seconds or taken from the player with Set from player, and only that part goes into the MP3. To cut a part out and keep the WAV, use the audio cutter.
Why will my WAV not open?
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Almost every WAV holds plain uncompressed sound, which opens here in any browser. A few recorders and old phones save WAV in a compressed form such as ADPCM, which browsers cannot read. Open it in an audio editor and save it as a standard WAV first.
Is my WAV uploaded?
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No. The WAV is read and converted inside this browser tab, and the MP3 is handed straight to your downloads. Nothing is sent to a server.