Free tool

Audio Compressor

Compress audio files to upload or email them. MP3, WAV, M4A. Free, in your browser.

Shrink large audio files for email attachments, upload limits, and faster sharing. Drop a file, export to MP3, and the compressor re-encodes it to a smaller size right in your browser, no upload, no sign-up.

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100% in your browser — your files never leave your device. Free, no sign-up.

How it works

How to use the Audio Compressor

  1. 1

    Add your audio

    Drop a file into the Audio Compressor or record straight in your browser. Nothing is uploaded — it runs on your device.

  2. 2

    Edit and adjust

    Trim, convert, tune the EQ, fades and levels, then preview instantly.

  3. 3

    Export or transcribe

    Download the result free, or turn it into a searchable transcript with one click.

Need a transcript?

Once you've cleaned up your audio, AuTrans turns it into a searchable transcript with speaker labels, summaries, and exports to TXT, DOCX, PDF, SRT, and VTT. Built for African languages: Nigerian English, Pidgin, Yoruba, Hausa, Igbo, plus French and Spanish.

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Frequently asked

Questions, answered

How do I compress an audio file?
Drop your file into the compressor, pick MP3 as the output, and export. The file is re-encoded to a much smaller size while keeping speech clear, all in your browser.
Will compressing reduce audio quality?
Compression trades some fidelity for size. For voice and podcasts the difference is inaudible at typical bitrates; for music, export at a higher bitrate to keep quality.
Is the audio compressor free and private?
Yes, it's free with no sign-up, and your audio never leaves your device because the compression runs entirely in your browser.
What formats can I compress?
MP3, M4A, OGG and WAV. WAV files shrink dramatically when exported to MP3, often by 80–90%.
Related transcription use cases
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Voice Memo Transcription
Transcribe iPhone / Android voice memos into searchable text notes.

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All part of AuTrans's free audio toolbox — quick, private, browser-based tools for the everyday audio jobs creators and teams actually do: cut, convert, compress, join, record. No sign-up, no watermarks, nothing leaves your device.

Start transcribing free

Get 30 minutes of free transcription every month. No credit card required. Just upload your audio and go.

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