Convert WAV to MP3
Shrink uncompressed WAV recordings to a tenth of the size, on your own device.
- Nothing is uploaded
- Works offline after first use
- Open source
- No sign-up, no watermark. The limit is your device’s memory (phones hold less).
Compress large WAV recordings to MP3 in your browser. Choose 128 to 320 kbps, batch convert. It is free, needs no account and adds no watermark, and your files are not uploaded: everything runs in your browser on your device. The limit is your device’s memory, which is smaller on a phone, and after your first run the page works offline.
Your iPhone may take a few seconds to prepare the video first, longer if it's stored in iCloud.
Done
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Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
WAV is uncompressed audio: every sample stored as it was recorded, about 10 MB per minute in CD-quality stereo. It is what recorders, DAWs and sample packs use, and it is far too large to email, upload to most sites or keep hundreds of on a phone. MP3 at 256 kbps is about a fifth of that, and at 128 kbps about a tenth, with no difference most listeners can hear.
Because WAV files are big, uploading them to an online converter is the slow part: a 45 minute rehearsal recording is close to half a gigabyte. This page reads the WAV straight from your disk and encodes it with LAME inside your browser, so there is no upload and the size limit is your device’s memory (phones hold less). Unreleased songs, stems and client recordings stay on your machine.
This page opens at 256 kbps, a good choice when the MP3 is the version you will share from a studio-quality source. Use 320 kbps for a master you will not re-encode again, or 128 kbps for demos and voice. Recordings made at 48 or 96 kHz are converted to 44.1 kHz, the standard MP3 rate.
Have a different kind of file? The MP3 converter takes any video or audio file.
How it works
- Drop one or more WAV files, or tap to pick them.
- Pick the MP3 quality: 256 kbps by default, 320 for the best, 128 for small files.
- Convert. Each MP3 downloads when it is ready; several come as a zip.
In your browser, not on a server
Your browser decodes the sound track with the same audio decoders it uses to play media on any website (AAC for MP4, MOV and M4A; Opus or Vorbis for WebM; FLAC, WAV and MP3). The samples are resampled to 44.1 kHz and handed to LAME, the reference MP3 encoder, compiled to WebAssembly and served by this site. WAV files are written directly by a few lines of code in the page. A WMA, which no browser plays, is decoded in a background worker by a separately loaded decoder module. Most video runs on your browser's WebCodecs through Mediabunny. For old formats the browser cannot read, the page loads a decoder built from FFmpeg's libraries (LGPL) only when you convert such a file. Everything happens in memory in your tab.
Compared with upload-based tools: Online converters upload the whole video just to keep its sound, cap free files at a few hundred megabytes, and make you wait in a queue. Home videos, lectures and voice memos are personal. Here the file never leaves your device, so a 1 GB video converts as fast as your computer can read it, and the limit is your device’s memory (phones hold less).
Verify it yourself. Give the page a short while after your first run to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
How much smaller is the MP3?
A CD-quality stereo WAV is 1,411 kbps. At 320 kbps the MP3 is about 4.4 times smaller, at 256 about 5.5 times and at 128 about 11 times. A 50 MB WAV becomes roughly 11, 9 or 4.5 MB.
Does it keep 24-bit or 96 kHz quality?
No. MP3 has no bit depth of its own and tops out at 48 kHz; this tool writes 44.1 kHz. For archiving a high-resolution master keep the WAV, and use the MP3 for sharing.
Are track names and cover art kept?
No. The MP3 contains the audio only, with no ID3 tags. Add titles in your music app after converting.
Is the file uploaded anywhere?
No. There is no server in this process. The page is a static file and the work is done by code running inside your browser tab. Give the page a short while after your first run to save itself for offline use; then you can turn off Wi-Fi and it still works.
More video and audio tools
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Vocal remover
Split a song into the music and the voice with an AI model running in this tab. Karaoke tracks and acapellas without uploading anything.
Video background remover
The person stays, the room goes: blurred, a flat colour or a picture of your choice, done frame by frame on your own device.
Other conversions
Guides
- How to convert a video to MP3This is different from muting a video: you want the sound saved as its own file. Most devices have no built-in way to do that.
- A free Zamzar alternative with no daily limitZamzar's free service limits how many files you can convert and how big each can be. Here is an alternative with no such cap.
- A free FreeConvert alternative with no processing time capFreeConvert's free plan limits the processing time for each file and for the day. Here is an alternative with nothing to time out.
- Is CloudConvert safe?For most files, yes: it is an established, certified service. The real question is whether a given file should leave your computer at all.
- Is FreeConvert safe?Yes: FreeConvert.com is a legitimate converter with a clear deletion policy, and fine for everyday files. Whether it is safe for a particular file depends on whether that file should be uploaded anywhere.