Mono / Stereo converts a recording between one and two channels. Downmix a stereo file to mono for a smaller size and consistent playback on single-speaker devices, or turn a mono source into stereo. It's a quick, lossless-friendly conversion done entirely in your browser.
Drop your file in and play it to hear the current channels.
Pick Mono to downmix to a single channel, or Stereo to output two channels.
Export to convert the channels and save the file.
Mono / Stereo converts a recording between one and two channels. Downmix a stereo file to mono for a smaller size and consistent playback on single-speaker devices, or turn a mono source into stereo. It's a quick, lossless-friendly conversion done entirely in your browser.
Mono files are about half the size and play consistently on single-speaker devices — ideal for voice, podcasts and phone audio.
Mono combines the left and right channels into one, so any stereo separation is lost, but the audio itself stays clear.
Converting mono to stereo copies the single channel to both sides; it won't recreate stereo separation that was never recorded.
Yes — Mono / Stereo is completely free. There's no account, sign-up, watermark or limit on the core tool.
No. This tool runs entirely in your browser — your file is processed on your own device and never leaves it. The only network request is an anonymous usage counter.
No. It runs in any modern browser — Chrome, Edge, Safari, Firefox, Brave — with nothing to download or install.