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MP3 to WAV Converter
This free MP3 to WAV converter turns your MP3 audio files into uncompressed WAV files right in your browser. Choose a file, pick the sample rate and channels, and download the WAV — your audio never leaves your device, because the whole conversion happens on your own computer. No uploads, no waiting in a queue, and no sign-up.
All processing happens in your browser. Your audio is never uploaded to any server.
How it works
MP3 and WAV store sound in opposite ways. An MP3 is compressed: when the file was made, the encoder threw away the parts of the sound that human ears are least likely to notice, such as very quiet tones hidden behind louder ones, and kept the rest. That is why a three-minute song fits in about 4 MB. A WAV file is uncompressed: it records the exact height of the sound wave thousands of times per second, which is why the same three-minute song needs about 30 MB. Converting MP3 to WAV unpacks the compressed sound back into that exact, sample-by-sample form.
This converter does the whole job in your browser. When you pick a file, the browser's Web Audio decoder reads the MP3 and turns it into raw sound samples, showing you the duration, sample rate, and channel count along the way. When you press Convert, those samples are written into a standard WAV file — a 16-bit PCM file with a proper WAV header — and offered as a download. Because nothing is uploaded, the conversion is as fast as your computer allows, and your audio stays private, which matters for personal voice memos, interviews, or unreleased music.
The sample rate setting controls how many samples each second of the WAV holds. Original keeps the rate the MP3 was decoded at, usually 44,100 Hz, and preserves the sound exactly as decoded. 44,100 Hz is CD quality and the right choice for music and general use. 22,050 Hz halves the file size and is fine for voice recordings, while 16,000 Hz is the rate many speech-recognition tools expect, and the smallest of the three. When the rate changes, the samples are re-spaced with linear interpolation, which keeps the pitch and timing correct. The channels setting works the same way: Keep original leaves stereo as stereo and mono as mono, Mono mixes the two channels into one, and Stereo duplicates a mono recording onto both channels.
Two things are worth knowing before you convert. First, the WAV will not sound better than the MP3. The detail that MP3 compression removed is gone for good, and unpacking the file cannot bring it back — the WAV sounds exactly the same, it is simply stored without compression. Convert to WAV because a program, an editor, or a device needs the uncompressed format, not to improve quality. Second, expect a much bigger file: at CD quality, one minute of stereo WAV is about 10 MB, so a whole album can be several hundred megabytes. That is normal for WAV, and it is the price of storing every sample exactly.
The output file keeps the same name as your input, with the extension changed to .wav, so a file called interview.mp3 becomes interview.wav, unless you type a different name in the file name box. The WAV plays in every audio editor, music player, and browser, because uncompressed WAV is the most widely supported audio format there is. If the converted file sounds wrong — too fast, too slow, or silent — the most likely cause is an unusual MP3, such as one with a very low sample rate; try converting again with the original sample rate and the original channels.
Worked example
A video editor has a music track called intro-music.mp3 that her editing program will only accept as a WAV file. The MP3 is 4.1 MB, stereo, 44,100 Hz, and 3 minutes 24 seconds long.
Step 1: Choose the file intro-music.mp3 in the file picker.
Step 2: The tool shows Duration 3:24, sample rate 44,100 Hz, 2 channels (stereo), 4.1 MB, and an estimated WAV size of about 34.3 MB.
Step 3: Keep Original sample rate and Keep original channels, then press Convert to WAV.
The tool writes a 16-bit PCM WAV file of 34.3 MB — 204 seconds × 44,100 samples per second × 2 channels × 2 bytes per sample — and the Download button saves it as intro-music.wav. The editor imports the WAV, and the music sounds exactly as it did in the MP3.
FAQ
Is my MP3 uploaded to a server?
No. The file is decoded and converted entirely in your browser, using JavaScript running on your own device. Your audio never leaves your computer, which is why this converter works even with private recordings.
Will the WAV sound better than the MP3?
No. Converting MP3 to WAV does not restore the sound detail that MP3 compression removed — the WAV sounds exactly the same as the MP3, it is simply stored without compression. Convert to WAV when a program or device needs the uncompressed format, not to improve quality.
Why is the WAV file so much bigger than the MP3?
A WAV file stores every sound sample exactly, with no compression. A three-minute stereo song at CD quality (44,100 Hz, 16-bit) needs about 30 MB, while the same song as a 192 kbps MP3 is only about 4 MB. The WAV is roughly ten times larger because it keeps data the MP3 threw away.
Which sample rate should I choose?
Keep the original sample rate for editing or archiving, because it preserves the file exactly as decoded. Choose 44,100 Hz for CD-quality audio and general use, 22,050 Hz for voice recordings where a smaller file matters, and 16,000 Hz for speech, voice notes, and speech-recognition tools that expect that rate.
Why did my file fail to convert?
The most common reason is that the file is not a real MP3 — for example, a different audio format renamed to .mp3, or a damaged download. Protected or encrypted files also cannot be decoded. Try the original file again, and if it still fails, re-export it as an MP3 from the program that made it.