Audio Compressor

Shrink an audio file so it fits in an email, on a podcast host, or under an upload limit. Pick a bitrate, optionally downmix to mono. Local — your file never leaves your tab.

drop audio here

MP3, WAV, M4A, FLAC, OGG, AAC. Drop several for batch.

How much can you shrink it?

It depends on what you started with. A 1-hour WAV recording is ~600 MB. The same hour at 128 kbps MP3 mono is ~28 MB — about a 95% reduction with no audible loss for voice. Music is more sensitive: 192 kbps stereo MP3 is usually indistinguishable from CD for casual listening, and 128 kbps stereo MP3 is fine for streaming over poor connections.

Picking a bitrate

FAQ

Will compressing an MP3 again make it worse?

Slightly — every lossy re-encode loses some fidelity. If you have the original WAV, compress that instead. If all you have is the MP3, the difference at 128 kbps and above is usually inaudible on consumer speakers.

Can I compress to WAV?

WAV is uncompressed by definition — there's no bitrate to lower, only the sample rate and bit depth. To meaningfully shrink a WAV you have to encode to a compressed format like MP3 or OGG.

Does this work offline?

Once the page has loaded, yes. You can disconnect from the internet and the tool still works.

What's the size limit?

Around 500 MB per file on a typical laptop. Browser memory is the bottleneck.

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