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Compress audio any format, free

By ShinobiTools Team · Last updated: September 2026

Got an audio file that's bigger than it needs to be? Drop in any format — WAV, FLAC, M4A, OGG, AIFF or even an oversized MP3 — and get back a smaller MP3 that plays everywhere. Free, no account, no watermark, up to 400 MB.

One converter, any format in

It doesn't matter what you start with. WAV and FLAC are uncompressed or lossless and can run into the hundreds of megabytes for a single album; a phone recording in M4A or OGG can still be bigger than it needs to be; even an MP3 exported at a high bitrate shrinks further. Drop any of them in and the output is the same: a compact MP3, encoded at a high-quality variable bitrate (around 190 kbps) that keeps voice and music sounding clean.

That's roughly a tenth the size of an hour of stereo WAV, and noticeably smaller than most FLAC rips or high-bitrate MP3 exports too.

What it doesn't do

This isn't a size-target tool like our video compressor, where you pick 8 MB or 25 MB and it hits that number. Audio doesn't need that: the same ~190 kbps encode already does most of the shrinking, so there's just one format menu — MP3, M4A or WAV — and MP3 is the one that shrinks the file.

About your file

The file is converted on our own server and the result comes straight back — the upload is deleted the moment the conversion finishes. No account, no e-mail, no watermark, no daily cap.

Starting specifically from WAV or FLAC? WAV to MP3 and FLAC to MP3 are the same converter, set up for those formats. Got a video instead of an audio file? Compress video shrinks that to an exact size. Volume uneven once it's an MP3? Audio volume booster evens it out.

Common questions

How do I compress an audio file online?

Drop it onto the box above — any format works — and download the MP3 that comes back. No account, no size-target menu to fiddle with.

Is it really free?

Yes. No account, no watermark, no per-file charge and no daily cap. Ads keep the machine running.

What formats can I compress?

WAV, FLAC, M4A, OGG, AIFF and MP3 all go in — anything a browser calls “audio”. You always get an MP3 back, which plays on everything.

How much smaller does it get?

Depends what you start with. An hour of stereo WAV shrinks by roughly ten times. FLAC and high-bitrate MP3 shrink less dramatically — the encode targets a high-quality ~190 kbps regardless of the input.

Will it ruin the quality?

For normal listening, no — the ~190 kbps variable bitrate used here is close to transparent for both speech and music. If you're archiving a master recording, keep the original and compress a copy.

Is my file uploaded?

Yes — a browser can't re-encode audio reliably across every format, so the file goes to our own server, gets converted and is deleted straight after.

Can I pick an exact target size, like the video compressor?

No — audio doesn't need that. The MP3 encode already does most of the shrinking; pick MP3, M4A or WAV from the format menu and download.

How is this different from the WAV to MP3 or FLAC to MP3 pages?

Same converter — this page just accepts any audio format instead of assuming you're starting from WAV or FLAC specifically.

How do I make an MP3 file smaller?

Drop it onto the box above with MP3 selected — it gets re-encoded at a smaller, still high-quality bitrate.