Why compress audio online?

WhatsApp limits audio attachments to 16 MB and emails to ~25 MB — compressing to 64-96 kbps solves it without audible loss for voice.

What if I need the text from this audio?

After compressing, you can transcribe the file with AI using VoxScriber: 30 free minutes per month, with automatic punctuation and speaker identification. Ideal for WhatsApp audios, meetings, and interviews.

Is Compress Audio Online Free really free?

Yes, free and unlimited. The processing happens in YOUR browser (WebAssembly), so we have no server cost — and you don't need to create an account.

Is my file sent to any server?

No. All processing is local (FFmpeg compiled to WebAssembly running on the page). The file never leaves your device — it even works offline after the page loads.

Is there a size or quantity limit?

The limit is 300 MB per file (browser memory). There is no limit on the number of uses. For larger files, VoxScriber processes on the server with uploads up to 5 GB.

Does it work on mobile?

Yes — any modern browser (Chrome, Safari, Firefox, Edge) on desktop or mobile. On older phones, large files may take longer.

Up to -80% · 64/96/128 kbps · Free · No Upload

Compress Audio Online Free — Reduce MP3 and WAV by up to 80%

Reduce the size of any audio by choosing the quality (64/96/128 kbps), right in your browser. Ideal for WhatsApp and email.

Drop your file here or click to select

Processed in your browser — up to 300 MB. Nothing is uploaded.

100% local processing: your file never leaves your device.

Formatos suportados: .mp4 files up to 300 MB — processed locally

Resultado em segundos

100% em português do Brasil

Privacidade garantida

Sem instalação

Como funciona

Upload the audio

Any common format, up to 300 MB.

Choose the quality

64 kbps (voice, maximum compression), 96 kbps (balanced), or 128 kbps (music). For voice audio, 64-96 kbps sounds nearly identical to the original.

Download the lightweight file

A 50 MB WAV becomes a ~5 MB MP3 — ready for WhatsApp (16 MB limit), email, and uploads.

Perguntas frequentes

Need the text from this audio? Transcribe it with AI — 30 min free

Criar conta gratuita →

30 minutos/mês grátis. Sem cartão de crédito.

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