11 / CHANNELS
Stereo to Mono
Mix left and right channels into one mono track on your device. Compare the original and result, then download MP3 or WAV.
Your audio stays on your device. No server upload.
Adjust the settings and compare the actual result.
Each tool lists its supported formats and limits.
Combine two channels into one
This converter mixes stereo MP3 or PCM WAV into a single mono channel using M = 0.5 × L + 0.5 × R. Both channels contribute equally. An already-mono input remains mono, although export still re-encodes it. Files are processed locally without upload.
How to convert stereo to mono
- Choose a mono or stereo MP3 or PCM WAV, up to 30 MiB and ten minutes.
- Review the channel-mixing warning. No phase correction or automatic loudness normalization is applied.
- Choose MP3 or 16-bit PCM WAV and create the audio.
- Compare the original and result, especially vocals, bass and wide stereo effects, then download.
Why sounds can disappear
If the right channel is the exact opposite of the left, equal mixing cancels the signal. Partial opposition can reduce specific sounds rather than the whole track. This is a consequence of summing the channels, not a silent-file export failure. The tool warns about this possibility but does not measure phase correlation or repair it.
Identical left and right signals keep their level under this averaging formula. A sound present on only one side is halved in amplitude, about −6.02 dB. Unrelated channels can behave differently; there is no promise of matching perceived loudness.
File size and quality
Mono PCM WAV uses half the stereo audio payload at the same duration, sample rate and bit depth. Headers and tags affect the actual size. A mono MP3 at the same constant bitrate is not necessarily half the size of a stereo MP3: the bitrate is the total encoded rate.
MP3 output is lossy; WAV uses 16-bit PCM. A 48 kHz source stays at 48 kHz and other accepted sample rates export at 44.1 kHz. Converting MP3 to WAV does not restore lost detail. Keep your stereo original because converting the mono result back to two channels cannot recreate spatial information.
What this tool does not do
It does not extract only the left or right channel, downmix surround sound, normalize loudness or remove vocals. Multichannel files beyond stereo are rejected. If you need M4A input, use M4A to MP3 first, noting that another MP3 export adds another lossy encoding step.
Read the mono mixing guide. To adjust overall level, use volume adjustment; to estimate size, use the calculator. Browse all tools.