Omnibus
  • 100% Free
  • No Sign-Up
  • No Credit Card
  • No Free Trial
  • No Pro Tier
  • No Watermarks

Nothing is uploaded. Just open it and start.

Compress audio files online

Free, no sign-up, no upload. Make MP3s and other audio smaller for email, messaging, or the web — choose a bitrate, optionally drop the sample rate or go mono, and see exactly how much you save. It all runs in your browser, so your file stays private.

Choose the bitrate

Pick 64–256 kbps to balance size against quality, with sensible defaults.

Sample rate & mono

Downsample or fold to mono to shrink voice recordings even further.

See the savings

Preview the compressed audio and the exact new size before downloading.

Private & client-side

No upload, no account — everything happens on your device.

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Trim MP3 and audio files on a waveform, add fade in/out, and export MP3 or WAV — a ringtone maker and clip cutter that runs in your browser. Nothing uploaded.

Voice Recorder

Record voice or mic audio in your browser with pause/resume and a live waveform, then download as WebM, WAV, or MP3. Nothing uploaded.

Vocal Remover

Remove or isolate vocals from a song in your browser with stereo phase cancellation, keep the bass, and download the instrumental as MP3 or WAV. Nothing uploaded.

Metronome

A steady, accurate metronome from 20–400 BPM with time signatures, subdivisions, and tap tempo.

Frequently asked questions

Is my audio file uploaded?
No. The file is decoded, re-encoded, and measured entirely in your browser — it never leaves your device, and there's no account. You only get a file when you press download.
How does the compression work?
It re-encodes your audio to MP3 at the bitrate you choose — a lower bitrate means a smaller file. You can shrink it further by lowering the sample rate or converting stereo to mono, which is ideal for voice.
Will it reduce the quality?
MP3 is a lossy format, so lowering the bitrate trades some fidelity for size. 128 kbps is transparent for most listening; 64–96 kbps is fine for speech. Your original file is never modified — compress a copy.
Which formats can I open, and what do I get out?
You can open MP3, WAV, M4A, OGG, and FLAC (anything your browser decodes). The compressed output is an MP3.
How much smaller will my file get?
It depends on the original. A 320 kbps track re-encoded to 128 kbps is roughly 60% smaller; a WAV compressed to MP3 shrinks dramatically. The tool shows the new size and the percentage saved after compressing.

Spotted a bug or have a suggestion?

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