Compress Audio Files

Audio files get big fast: a one-hour WAV recording is about 600 MB, and even a high-bitrate MP3 of a long lecture can be over 100 MB – too much for email, WhatsApp or an upload form. Compress Audio shrinks music, voice notes, podcasts and recordings by re-encoding them at a lower bitrate. The page starts at 64 kbps MP3, which keeps speech perfectly clear at a small fraction of the original size.

How to Compress an Audio File

1. Add the audio files – MP3, WAV, M4A, OGG, FLAC and more, one or many.
2. Pick a bitrate from the guide below; 64 kbps is preset.
3. Choose Mono for voice recordings – it halves the size again with no loss of clarity for speech.
4. Click Convert and download the smaller files.

The estimated output size appears before you convert, so you can try settings until the file fits your limit.

Bitrate Guide

• 32 kbps mono – voice notes, phone calls, dictation. About 15 MB per hour.
• 64 kbps mono – lectures, meetings, audiobooks. About 30 MB per hour.
• 96–128 kbps stereo – podcasts with music, casual music listening. About 45–60 MB per hour.
• 160–192 kbps stereo – music where you still want good quality, at roughly half the size of a 320 kbps file.

Example Savings

• A 45-minute WAV meeting recording (around 450 MB) → about 20 MB at 64 kbps mono.
• A 10 MB, 4-minute 320 kbps song → about 4 MB at 128 kbps.
• A 60 MB voice memo exported from a phone → under 15 MB at 32 kbps mono.

Shorter Is Smaller, Too

Cut silence at the start and end with Audio Cutter, or remove long pauses throughout with Remove Silence. Less audio means a smaller file at any bitrate.

Compression Is One-Way

Lower-bitrate MP3s discard sound detail that cannot be restored later. Keep your original if you might need full quality again, and compress a copy for sharing.

Private and Free

Files are compressed inside your browser – recordings of meetings, interviews and calls are never uploaded. No sign-up, no watermark.

MP3 Bitrate Changer Audio Converter Cut Audio Remove Silence Video to MP3