Free Stereo to Mono Audio Converter

Turn a stereo file into a single mono channel. Mix left and right, or keep just one side, and hear the result before you download it.

Online Stereo to Mono Tool

A mono file plays the same sound from every speaker. Converting to mono fixes recordings that come from one side only, halves the file size and makes sure nothing is missing on phones and single speakers.

What Can the Stereo to Mono Converter Do?

  • Mix left and right: the two channels are added and halved, the standard way to make a mono file.
  • Keep one channel: use only the left or only the right channel, for example when a microphone was recorded on one side.
  • Check the phase: a meter shows how well the two channels agree, and the tool warns you when mixing them would cancel part of the sound.
  • Compare: switch between the mono result and the stereo original while the audio plays.

Which Option Should You Choose?

If the recording is a voice on one side and silence on the other, choose that channel: mixing it with the silent side would only halve its level. If both sides carry sound, mix them. The meter tells you what to expect: near +1 the channels are almost the same and nothing is lost; around 0 they differ a lot, as in a wide stereo recording, and the mix comes out about 3 dB quieter; below 0 they work against each other, and the bass or even the whole signal can disappear. In that case keep one channel, or flip one side with the Phase Inverter first. What Is Phase Cancellation? (And How to Fix It) explains why this happens.

Who Is It For?

Podcasters and interviewers with a voice on one side only, video editors fixing camera audio, musicians checking how a mix holds up in mono, and anyone who wants smaller files for speech. The background is in Stereo vs. Mono Audio: What Is the Difference?.

How to Convert Stereo to Mono in 3 Steps

Step 1

Open Your Audio

Choose a file from your device. MP3, WAV, FLAC and M4A work in all modern browsers; OGG depends on your browser.

Step 2

Choose How to Convert

Pick mixing left and right, the left channel only or the right channel only, and check the meter.

Step 3

Listen and Download

Press Play to hear the mono result, then click Download Mono WAV.

Select Audio File

Drag and drop a file here or choose one from your device. Supported formats: MP3, WAV, FLAC, M4A and OGG (OGG depends on your browser).

Your waveform will appear here after you choose a file.

Time: 00:00 / 00:00
Tip: Use headphones to hear the changes clearly. On a phone, make sure silent mode is off.

Conversion

Channel agreement --
-10+1

Export Mono Audio

The file is exported as a 16-bit WAV with the same sample rate and channels as the original.

Tip: Need an MP3? Export a WAV here, then convert it.
WAV to MP3 Converter

Frequently Asked Questions

Is the Stereo to Mono Converter really free?
Yes. The Stereo to Mono Converter is free to use, with no sign-up and no daily limits.

Are my audio files safe and private?
Yes. The audio is processed in your browser on your own device. Your files are never uploaded to our servers.

What does converting stereo to mono do?
It reduces the two channels of a stereo file to one. A mono file plays the same sound from the left and the right speaker, so nothing is positioned to one side any more.

Why does my recording play in one ear only, and how do I fix it?
A single microphone was recorded onto one channel of a stereo track. Open the file, choose the channel that carries the sound and download the mono file; it then plays in both ears.

Does converting to mono reduce the quality?
The stereo width is lost; the sound itself is not degraded. The exception is a file whose channels are out of phase: mixing them cancels part of the sound. The meter warns you about that, and keeping one channel avoids it.

Why is the mono file quieter than the stereo original?
When the two channels differ, they do not add up fully. A wide stereo mix loses around 3 dB when it is mixed to mono, and a sound that exists on one side only loses 6 dB. The tool shows the expected change.

Is a mono file smaller?
Yes. A mono WAV is half the size of a stereo WAV of the same length, because it stores one channel in place of two.

Which formats can I open?
MP3, WAV, FLAC and M4A files open in all modern browsers; OGG depends on your browser. The result is downloaded as a 16-bit mono WAV at the original sample rate.

Do I need to install any software?
No. The tool runs in your web browser on computers, phones and tablets.