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MP3 to WAV

Decode an MP3 into an uncompressed WAV. Nothing MP3 already discarded comes back; the result is only a format older software and hardware samplers can read, several times larger for the same audio.

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MP3 to WAV expands a compressed file back into raw PCM samples saved as an uncompressed WAV. Detail the original encoder threw away does not return; the point is a format that legacy editors and hardware samplers open, at several times the file size. Decoding runs through WebCodecs, so this page needs a browser tab.

Questions

Does this restore any quality?

No. Nothing MP3 already discarded comes back; decoding to WAV only stops further loss from this point on, storing whatever samples the decoder produces without compression.

Why would anyone want a bigger, uncompressed file?

Compatibility. Some older software and hardware samplers read WAV but not MP3 directly, so this trades file size for a format more programs can open, several times larger for the same audio.

Which engine handles this, and where can it run?

mediabunny and WebCodecs decode the MP3 and write uncompressed PCM samples into a WAV container. This is browser only; the command line and MCP refuse it and point to the web page, since decoding runs through WebCodecs even for an uncompressed target.

What size should I expect?

A real WAV several times larger than the source MP3 for the same duration, with a proper RIFF/WAVE header and plausible channel count and sample rate, verified against the fixture test.

What is the reverse page?

WAV to MP3 runs the opposite direction, the reverse pair of this one, compressing the uncompressed audio down by roughly a factor of ten at the default quality.

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