How is this different from the channel mixer?

It is the same exchange, with the matrix already chosen and no controls to get wrong. The mixer exposes all four coefficients so you can build combinations, sums and difference signals, while this tool performs the one operation that people most often want and nothing else.

Is the swap lossless?

Yes. Samples are moved between channels rather than altered, so there is no gain change, no rounding and no resampling. The operation is exactly reversible, which is verified behaviour: run it twice on the same file and you get the original samples back.

Can it fix a mono recording that should have been stereo?

No. With one channel there is nothing to exchange, and the tool refuses the file rather than inventing content. Correcting a genuinely mono capture means either re-recording or creating a synthetic second channel, which is what the mono to stereo converter is for.

How do I know a recording is actually flipped?

Compare it with something you trust, such as a reference track or your own voice recorded on a known correct setup. A mirrored capture usually reveals itself when an instrument or a positional cue appears on the wrong side. The tool always performs the swap, so the decision is yours to make first.

Does swapping affect the stereo image in any other way?

No. It is a pure position change, so width, balance and levels are untouched. Nothing about the file is rerendered, and the only audible difference is that content which was on the left is now on the right, and the reverse.

Left/Right Channel Swapper

You Might Also Need

Channel Inverter

Invert audio channel polarity

Channel Mixer

Mix and balance audio channels

Channel Isolator

Isolate left or right channel

Phase Inverter

Invert phase 180 degrees

Left/Right Channel Swapper exchanges the two channels of a stereo file and changes nothing else. It is the one job tool for flipped captures and headphones that seem inside out on a recording you trust.

What is Left/Right Channel Swapper?

Drop a stereo file and download the swapped version. Every sample in the left channel moves to the right and every sample in the right channel moves to the left, with no gain change, no filtering and no processing beyond the exchange itself.

When an exchange is the right repair:

A recording captured with the two inputs of an interface plugged in the wrong way round.
A mislabeled capture from a camera or phone whose sides play mirrored against reference material you know is correct.
A stereo split from a film or broadcast source that arrived with the sides transposed.
A monitoring check where you want to confirm by ear that a swap is what fixes the perceived image.

The swap is one application of the two by two channel matrix used elsewhere in this domain, with coefficients chosen so that output left is right and output right is left. Because the matrix only moves existing samples between channels, the operation is exactly reversible: running the tool twice on the same file returns the original samples. Verified behaviour is that the exchange is exact, with no rounding, no level shift and no change to length or sample rate. The file must have at least two channels, and a mono input is refused rather than having a second channel invented for it to swap with.

What a swap cannot do:

It needs a stereo file and does nothing useful with mono, which has no second channel to exchange.
It cannot repair a recording where one channel was lost, clipped or damaged; it only relocates what is there.
It is not a balance control, so it cannot shift the image part of the way across.
Swapping does not tell you which orientation was correct in the first place, so the judgement is still yours.
Multichannel layouts beyond two channels are out of scope, so surround files are not handled.
The result is written as a new WAV rather than replacing the file you loaded.

A channel swap is worth confirming before you use it, because a mirrored file is rarer than it feels. If a recording sounds wrong on headphones but correct on speakers, the cause is far more likely to be a monitoring difference than a flipped capture, since a genuine swap is audible on any playback system. The reliable test is a comparison against reference material you trust rather than your impression of the file on its own. Keep the original until the swapped version has been checked. If the need is to combine or rebuild the two channels rather than exchange them, the channel mixer gives you the full matrix; if the problem is polarity rather than position, the channel inverter and the phase inverter are the right pair. If you are unsure which side is correct, the safest habit is to keep a copy of the file that the swap did not touch and compare the two by ear on the system where the problem first showed up, because a mirrored capture is a claim about the source rather than about the listener.

How to use Left/Right Channel Swapper

Drop a stereo audio file onto the panel; a mono file will be rejected because there is nothing to exchange.
Run the swap, which exchanges every sample of the left and right channels in a single pass.
Download the swapped WAV and compare it with the original on the system where the flip was noticed.
Run the tool a second time on its own output if you want to confirm the exchange is exactly reversible.

When to use Left/Right Channel Swapper vs related tools

Left/Right Channel Swapper is the single purpose answer when a capture is mirrored and nothing else needs changing. Channel Inverter is the neighbouring repair for polarity rather than position, and Channel Isolator discards one side instead of exchanging them. When the relationship between the channels needs to be rebuilt rather than reversed, Channel Mixer has the full matrix, and Phase Inverter flips everything at once when the whole file is out of polarity with a reference.

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