Stereo to Mono Converter

Why Downmix to Mono

Stereo is not universal on the playback side. Plenty of club systems and venue setups run mono or near-mono, a summed main-and-sub array, a single stack in a small room, so checking how a mix holds up in mono is a standard step before a track goes out, not an edge case. It also comes up outside the club: a phone recording captured with one working mic channel, a voice memo, or any source where one side of a stereo pair was silent or unreliable, ends up needing exactly this treatment to become a clean, usable mono file rather than a stereo file with a dead channel.

Phase Cancellation: What You Might Hear

This tool sums all channels sample by sample and divides by the channel count, the standard downmix. If content on the left and right channels is out of phase, meaning one is roughly the inverse of the other, that content partially or fully cancels when summed, and the mono result can lose level, thin out, or lose bass and vocal presence compared to the stereo version. That is not a bug in the conversion; it is a property of the source mix. Hearing it here is precisely the mono-compatibility check producers and mastering engineers run intentionally, so they can catch and fix phase issues before a release ships to systems that will play it summed.

Output and Privacy

Decoding, the downmix, and re-encoding all run in your browser, the same as the other tools on this page: nothing is uploaded, and both a WAV and a 320 kbps MP3 download are generated for each file. WAV output is close to half the size of the original stereo WAV, since it stores half as much raw sample data. If a file dropped here is already mono, it is passed through unchanged and the tool tells you so.

Related Tools

Going the other direction, duplicating a mono file into two channels, use the Mono to Stereo Converter. To even out levels after the channel count is right, run the file through the Audio Normalizer, and if you need a different file format entirely, the WAV to MP3 converter handles that in the same private, in-browser way.

Frequently Asked Questions