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MP3 to WAV Converter

Decode an MP3 and write its samples as a standard 16-bit WAV file in this tab, ready for an editor or a CD-burning program, with nothing uploaded.

Open an MP3 file

· or drop one anywhere on the stage

Never uploadedNo accountUp to 50 MBUp to 10 minutes
From
To
Bit depth
Sample rate
Channels
Download

Ready. Choose an MP3 file, or drop one on the stage.

The MP3 is decoded once, in this tab, after its frame header is read. The output is uncompressed 16-bit PCM at the sample rate you choose, which does not restore anything a lossy file already lost: it is a larger file, not a better one.

  • What the bytes sayread from the first bytes of the file, never from its extension
    Open a file and its container is identified before anything is decoded.
  • Output sizeexact arithmetic for PCM, an estimate for MP3
    Open a file to size the output.
  • Decoderasked of this browser before a conversion starts
    A codec with no decoder here is named up front, not halfway through.

The From control is a mode, not a guess: the first bytes of the file are read and checked against it, so a file that was renamed is refused with what it actually is. A bare AAC opens in M4A mode, a FLAC in WAV mode, and a MOV or WebM video in MP4 mode. An MP4 has its audio tracks listed before anything is extracted and its video is never decoded. Changing the sample rate resamples by linear interpolation, and changing the channel count averages a stereo pair down or copies a mono channel to both sides.

Two open source parts do the heavy lifting. Containers are parsed and audio is decoded by Mediabunny 1.55.7 under the MPL-2.0 (licence text, the exact package, source). MP3 encoding is lamejs 1.2.7 under the LGPL-3.0 (licence text, the exact package, corresponding source). Both are bundled unmodified at those versions and loaded from this page, never from another service.

Common questions

How do I convert MP3 to WAV?
Leave From on MP3 and To on WAV, press Open audio or drop the MP3 on the stage, pick 44.1 or 48 kHz and mono or stereo, press Convert and then Download. The exact WAV size is printed before you start.
Does MP3 to WAV improve sound quality?
No. A WAV avoids another lossy encode and holds exactly the samples the MP3 decodes to, so what you gain is an editable, uncompressed file rather than better sound.
Are files uploaded?
No. The file is decoded and written entirely in your browser.

Files are decoded and re-encoded in your browser, so nothing is uploaded. Converting cannot restore detail a lossy file already lost, and an MP3 output is a lossy encode of its own. Which formats can be decoded depends on your browser, and this page checks the file's actual bytes and its codec before starting rather than trusting the extension.