Copy a mono recording into matching left and right channels and export a two-channel audio file.
Drop audio here, or click to select
Audio and video files are processed locally in your browser and are not uploaded.
Converting mono to stereo duplicates the same mono signal into the left and right channels. This creates a two-channel file for compatibility, but it does not add stereo separation or new spatial detail.
A two-channel output can help when an editor, player, streaming service, or production workflow expects stereo input even though the source contains only one channel.
Both output channels contain the same waveform. To create audible width, process the channels differently with delay, equalization, or other effects after conversion.
Choose an output format, create the stereo result, and listen to it before downloading. Processing takes place locally in your browser.
No. It duplicates the same mono signal into left and right channels. The output is a two-channel file, but both channels contain the same spatial information.
Use it when an editor, player, streaming service, or delivery specification expects two channels even though the recording itself is mono.
The sound should remain centered because the two output channels match. File size may increase because two channels are stored, depending on the selected format and encoder.
Choose Fill both channels and select the side containing sound. That side is copied to both outputs. This differs from a true mono input: a stereo file may contain two channels with one silent.
Related tools: Audio Channel Converter · Stereo to Mono · Extract Left · Extract Right · Swap Channels · Invert Polarity
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