Mono / Stereo Converter
Convert audio between mono and stereo channels instantly in your browser — no upload.
100% in your browser
No watermark
No sign-up
How it works
- Drop any audio file — it stays entirely on your device.
- Choose a conversion direction: Stereo → Mono or Mono → Stereo.
- Click Convert — the processed file downloads automatically. Nothing is uploaded.
Frequently asked questions
- What does converting stereo to mono do?
- It mixes both the left and right audio channels into a single channel, halving the channel count. This is useful for voice recordings, podcasts, or reducing file size when stereo is unnecessary.
- What does converting mono to stereo do?
- It duplicates the single mono channel into both the left and right channels, producing a stereo file. The audio will sound the same in both ears — it does not add spatial width that was not in the original.
- Are my audio files uploaded to a server?
- No. The conversion runs entirely in your browser using WebAssembly — your files never leave your device.
- Which audio formats are supported?
- Any format that FFmpeg supports in the browser: MP3, WAV, OGG, M4A, AAC, FLAC, and more. The output file keeps the same format (extension) as the original.