Can it convert to MP3?

No. Browsers cannot encode MP3 without a bundled codec many megabytes in size. Every output here is WAV.

Why is the converted file so much bigger?

WAV stores every sample uncompressed — about 10 MB per minute at CD quality. Compressed formats are 10 to 20 times smaller.

Does resampling lose quality?

Lowering the rate discards the highest frequencies, which is unavoidable. Raising it adds no detail and only makes the file bigger.

Audio Converter

Convert audio to WAV, with sample rate, bit depth and mono mixdown options.

Runs in your browserNo account neededFree

Processing: This tool runs entirely in your browser. Your input and any file you open stay on your device — nothing is uploaded to a server. Decoded entirely in memory, so length is limited by your device rather than a server quota. Files over about 20 minutes are slow.

How to use the audio converter

Open the audio file.
Choose a sample rate and bit depth, or keep the original.
Convert and download the WAV.

About this tool

Anything the browser can decode — MP3, M4A, OGG, FLAC, WAV — can be converted here to WAV, optionally resampled and mixed to mono. Resampling goes through an offline audio context, which interpolates properly rather than dropping samples, so reducing 48 kHz to 44.1 kHz does not introduce artefacts.

Expect the file to grow. WAV is uncompressed at roughly 10 MB a minute at CD quality, so a 4 MB MP3 becomes a 40 MB WAV. That is the honest cost of converting without a compressed encoder, and it is why this is useful for editing and archiving rather than for sharing.

Browsers can decode MP3, M4A, OGG and FLAC, but the only format they can reliably write is WAV — so the output here is WAV. Exporting MP3 would mean bundling an encoder several times the size of this entire site, which is not a trade worth making for a tool you use once.

Common uses

Getting a WAV for an editor that will not read M4A.
Downsampling a recording for a system that needs 16 kHz.
Mixing a stereo voice recording down to mono.

Frequently asked questions

Can it convert to MP3?: No. Browsers cannot encode MP3 without a bundled codec many megabytes in size. Every output here is WAV.
Why is the converted file so much bigger?: WAV stores every sample uncompressed — about 10 MB per minute at CD quality. Compressed formats are 10 to 20 times smaller.
Does resampling lose quality?: Lowering the rate discards the highest frequencies, which is unavoidable. Raising it adds no detail and only makes the file bigger.

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