📦 Audio Compressor

Reduce audio file size by adjusting bitrate and sample rate — output as MP3, no upload

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Drop audio file here or click to browse

MP3, WAV, FLAC, OGG, M4A — processed locally, never uploaded

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Bitrate Control
Choose from 64 to 320 kbps for the right size vs quality.
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Sample Rate Options
Downsample to 22 kHz or 16 kHz for even smaller files.
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Size Preview
See the estimated output size before you compress.
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100% Private
All compression in your browser. Files never leave your device.

Free Online Audio Compressor

Audio Compressor reduces the file size of your audio by re-encoding it to MP3 at a bitrate and sample rate you choose. Perfect for fitting audio into email attachments, messaging apps, or storage limits.

How It Works

Lossy MP3 compression removes inaudible data to shrink the file. A 44 MB WAV can become a 4 MB MP3 at 128 kbps — roughly a 10x reduction with minimal quality loss for most uses. Higher bitrates (256–320 kbps) preserve more detail for music. Everything runs in your browser via the Web Audio API and a JavaScript MP3 encoder — nothing is uploaded.

Choosing the Right Bitrate

64 kbps — voice recordings and podcasts (smallest files). 128 kbps — general purpose, good quality for most uses. 192 kbps — high quality for music. 320 kbps — maximum quality, indistinguishable from uncompressed for most listeners. Lowering the sample rate to 22 kHz or 16 kHz shrinks speech files further.

Need other edits? Try our Audio Converter, Audio Trimmer, Audio Joiner, or Volume Booster.

Frequently Asked Questions

How much can I reduce file size?
Depending on the source, you can reduce WAV files by 5–20x by converting to MP3. A 50 MB WAV becomes ~5 MB at 128 kbps.
Does compression affect quality?
Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original.
Is my audio uploaded?
No. All compression happens in your browser using the Web Audio API.