Convert WAV to MP3, right in your browser
Turn big WAV files into MP3s you can actually email, up to 320 kbps. The encoding happens on your device, so unreleased mixes and client recordings never touch a server.
Starting the converter. It needs JavaScript, because JavaScript is what does the conversion here instead of a server.
- Nothing leaves your device. Useful when the WAV is a master you have not released.
- Bitrates up to 320 kbps. Every option is free, including the good ones.
- LAME under the hood. The same encoder Audacity and ffmpeg use.
- Whole folders at once. Queue them up and download one ZIP at the end.
How to convert WAV to MP3
- Add your WAV files. Click the button or drag them onto the drop area. The converter also accepts other audio your browser can decode, so an M4A or an OGG will work.
- Choose a bitrate. 192 kbps is a sensible default. Open Output settings to move up to 320 kbps or down to 96 kbps for speech.
- Download. Play the result in the small preview player first if you want to check it, then save the MP3 or take the whole batch as a ZIP.
Choosing a bitrate without overthinking it
Bitrate decides how much data the encoder is allowed to keep per second. More data means a larger file and less audible damage. There is no single correct answer, only a trade you are making on purpose.
| Bitrate | One minute, stereo | Good for |
|---|---|---|
| 320 kbps | 2.3 MB | Music you care about, client deliverables, anything that might get re-encoded later |
| 256 kbps | 1.8 MB | Music, when you want most of the quality and a smaller file |
| 192 kbps | 1.4 MB | General listening. Hard to fault on normal speakers and headphones |
| 128 kbps | 0.9 MB | Background music, long recordings, upload limits you have to squeeze under |
| 96 kbps | 0.7 MB | Speech, podcasts, voice memos, lectures |
One rule is worth following: encode from the WAV, not from another MP3. Every trip through an MP3 encoder adds damage on top of the last one, and the second generation is the one people start to notice. More on what bitrate actually changes.
When MP3 is the right answer
WAV is the format you work in. MP3 is the format you send. A four minute stereo WAV is about 40 MB, which is more than plenty of email systems and messaging apps will accept, and more than a listener wants to download to hear one track.
- Sending a rough mix to a bandmate, client, or collaborator for feedback.
- Uploading to platforms that re-encode anyway, where a 320 kbps MP3 loses nothing you would keep.
- Filling a phone, car stereo, or old MP3 player where storage runs out before quality does.
- Podcast and lecture recordings, which are speech and compress extremely well.
- Archiving reference copies while the WAV masters live on a drive somewhere.
If the destination is a DAW, a CD burner, or a video timeline, stay with WAV. The full comparison is here.
What you will save
WAV file size is fixed by the audio format, not by the music. A stereo 44.1 kHz 16-bit WAV costs 10.1 MB every minute whether it holds a drum solo or silence. MP3 changes that completely.
| Source | 4 minute track | 1 hour recording |
|---|---|---|
| WAV, 44.1 kHz 16-bit stereo | 40.4 MB | 606 MB |
| MP3 at 320 kbps | 9.2 MB | 137 MB |
| MP3 at 192 kbps | 5.5 MB | 82 MB |
| MP3 at 128 kbps | 3.7 MB | 55 MB |
| MP3 at 96 kbps, mono speech | 2.7 MB | 41 MB |
What the converter does
Your browser decodes the WAV using the Web Audio API, the same code path it uses to play audio on any web page. We read the sample rate straight from the WAV header first, so a 48 kHz recording stays at 48 kHz instead of being quietly resampled.
The decoded samples then go to a background worker running LAME. MP3 only supports a fixed set of sample rates, so anything unusual, a 96 kHz session file for example, is resampled to 48 kHz before encoding. Everything else passes through untouched.
LAME is licensed under the LGPL. We serve it as a separate, unmodified file, and the licence text sits at /vendor/LAME-LICENSE.txt.
Questions people actually ask
Is the WAV to MP3 converter free?
Yes. No account, no upload limit, no paid tier that unlocks the good bitrates. Everything runs on your machine, so there is no server cost for us to pass on to you.
Are my WAV files uploaded to a server?
No. The file is read from your disk, decoded, and re-encoded in the same browser tab. Open the Network tab in your developer tools while you convert and you will not see an upload. That matters more than usual here, because WAV files are often unreleased masters, client work, or recordings of private conversations.
What bitrate should I use?
192 kbps is the default because it sounds clean for almost everything and keeps files small. Use 320 kbps for music you care about or anything a client will hear. Drop to 96 or 128 kbps for speech, podcasts, or voice notes, where the extra data does very little.
How much smaller will my file get?
A one minute 44.1 kHz 16-bit stereo WAV is 10.1 MB. At 320 kbps it becomes 2.3 MB, at 192 kbps 1.4 MB, and at 128 kbps 0.9 MB. So expect somewhere between four and eleven times smaller depending on the bitrate you pick.
Does converting WAV to MP3 lose quality?
Yes, by design. MP3 is a lossy format: the encoder removes audio it predicts you will not notice in order to shrink the file. At 320 kbps most people cannot hear the difference in normal listening, but the data is gone either way. Keep your WAV masters and treat the MP3 as a copy for sharing.
Which MP3 encoder does this use?
LAME, through the lamejs JavaScript port. LAME is the same encoder behind Audacity and ffmpeg, and it has been the reference quality MP3 encoder for two decades. It is licensed under the LGPL and we serve it unmodified from /vendor/lamejs.min.js.
Can I convert a folder of WAV files at once?
Yes. Add as many as you want and they encode one after another, with a progress bar for each. When two or more are done, Download all as ZIP saves you clicking through them individually.
Why is encoding slower than converting to WAV?
Because MP3 encoding is real work. Writing a WAV is mostly copying numbers, while LAME analyses the audio and decides what to throw away. A four minute track usually takes a few seconds. The encoding runs in a background thread, so the page keeps responding while it works.