Private audio tool
Compress Audio Online
Shrink MP3, WAV, M4A, FLAC, or OGG audio locally and download a smaller MP3. Choose a bitrate for music, voice, or minimum size while keeping the source file on your device.
File
No audio selected yet.How online audio compression works
This tool runs locally in your browser with ffmpeg.wasm. It strips any video stream, encodes the audio as MP3, and creates a local download link when compression finishes.
Choose 128 kbps for everyday listening, 96 kbps for voice and spoken recordings, or 64 kbps when reducing file size matters more than music detail. The result card shows the original and compressed sizes so you can judge the saving.
The first media operation in a tab downloads the roughly 31 MB engine once. Browser memory is still the limit, so very large recordings may be refused before processing.
Does this upload my files?
No. Everything on this page runs locally in your browser, so your files are never uploaded to a conversion server. Close the tab and nothing is left behind.
After any required processing engine has loaded, repeated conversions can keep working offline. You can verify the claim with the site's reproducible browser privacy audit.
FAQ
Is my audio uploaded?
No. The selected audio is decoded, compressed, and downloaded locally inside your browser.
Why does the first run download an engine?
Audio compression uses ffmpeg.wasm. The browser downloads the roughly 31 MB engine once, then reuses it while the tab is open.
Will the page show how much smaller the audio is?
Yes. The file card shows the original size and the compressed output size after the MP3 is ready.
Which bitrate should I choose?
Use 128 kbps for general listening, 96 kbps for voice and smaller sharing files, or 64 kbps when size matters more than detail.
Which audio formats can I compress?
Choose an MP3, WAV, M4A, FLAC, or OGG file. The compressed download is an MP3 using the bitrate you select.