MP3 to WAV
Decode MP3 files to standard PCM WAV that any editor, DAW or CD burner will accept.
To convert MP3 to WAV, drop the MP3 into the MP3 to WAV tool, choose a Sample rate of 44.1 kHz (CD) or 48 kHz (video), click Convert to WAV and download the file. FFmpeg decodes the MP3 to 16-bit stereo PCM, so the WAV is about 10 MB per minute, roughly ten times the size of the MP3.
FFmpeg (about 30 MB) is downloaded once on first use and cached by your browser. Speed depends on your device.
How do I convert MP3 to WAV?
- Drop one or more MP3 files onto the drop zone, or click to browse.
- Choose a Sample rate: 44.1 kHz (CD) for music, CD burning and most editors, or 48 kHz (video) if the audio is going into a video project.
- Click Convert to WAV.
- Wait a few seconds per file while FFmpeg decodes the audio.
- Download each WAV, or Download all as ZIP when you converted several.
WAV is the plainest audio format there is: a short header followed by raw PCM samples. This tool decodes each MP3 with FFmpeg and writes the samples as 16-bit signed little-endian PCM (pcm_s16le) in stereo at the sample rate you chose. There is no compression, so the WAV is about 10 MB per minute at 44.1 kHz and 11 MB per minute at 48 kHz, roughly ten times the size of a 128 kbps MP3.
Converting to WAV does not restore anything the MP3 encoder threw away; it simply unpacks what is there into a form other software can read without a decoder. That is still useful. Audio editors and DAWs open WAV instantly and work on it without generation loss, CD burning software expects 44.1 kHz 16-bit PCM, and some samplers, video editors and legacy systems refuse MP3 altogether.
Sample rate is the only decision. 44.1 kHz is the CD standard and the right choice for music and anything destined for a CD or a music editor. 48 kHz is the video and broadcast standard, so choose it when the audio will sit alongside video in Premiere, DaVinci Resolve or Final Cut, which saves the editor resampling it later. If the MP3 was encoded at a different rate, FFmpeg resamples it cleanly.
Decoding MP3 is light work, so a 5 minute track finishes in a few seconds on a laptop and well under a minute on a phone. Everything runs in your browser through FFmpeg compiled to WebAssembly, downloaded once (about 30 MB) and cached. Nothing is uploaded. Because the output is large, an album's worth of WAV can approach the browser's roughly 2 GB memory ceiling, so convert long sets in a few batches.
How it works: this tool uses FFmpeg compiled to WebAssembly (ffmpeg.wasm), loaded into your browser. No server is involved, so Kilnfile never sees your file. Last reviewed 20 September 2026.
Frequently asked questions
Does converting MP3 to WAV improve the quality?
No. The detail removed when the MP3 was made is gone for good; WAV just stores what remains without further loss. The benefit is compatibility and editability, not sound quality.
Why is the WAV so much bigger than the MP3?
WAV is uncompressed PCM at about 10 MB per minute for 44.1 kHz stereo. A typical MP3 at 128 kbps is about 1 MB per minute, so the WAV is roughly ten times larger. That is normal and expected.
Which sample rate should I pick?
44.1 kHz for music, CD burning and general use. 48 kHz if the audio is going into a video project, since video editors work at 48 kHz. When in doubt, choose 44.1 kHz.
Is the WAV 16-bit or 24-bit?
16-bit, which is what CDs use and what almost every application expects. MP3 carries no more than 16 bits of useful resolution anyway, so a 24-bit WAV would only be larger, not better.
Is my audio uploaded?
No. The MP3 is decoded inside your browser by FFmpeg running as WebAssembly and the WAV is saved straight to your device. There is no server, no signup and no file limit beyond your browser's memory.
Cite this page: “MP3 to WAV Converter, Free and No Upload”, Kilnfile, https://kilnfile.com/media/mp3-to-wav/
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Guides
- Audio formats and bitrates explainedMP3, AAC, WAV and FLAC compared with real file sizes per minute. Which bitrate you can actually hear, and when converting loses nothing at all.
- How to make a GIF from a videoTurn a clip into a GIF in your browser: pick the start, duration, frame rate and width, and keep the file under the limits for Slack, X and websites.