How it works
- Drop your audio file. MP3, WAV, FLAC, AIFF, OGG or M4A up to 500 MB — it's decoded locally, nothing is uploaded.
- Choose the channels and invert. All channels (the usual case), left only or right only for stereo troubleshooting.
- A/B and download. Switch between the original and the inverted version on the waveform, then export in the same format as your source.
Features
- Three inversion modes. Invert every channel, the left channel only, or the right channel only.
- A/B preview. Compare the original and the inverted version on the waveform before downloading — switching is free.
- Same-format export. Lossless sources stay lossless (WAV, AIFF, FLAC); lossy sources are re-encoded at high quality.
- 100% in your browser. Your track never leaves your computer — processing runs locally with ffmpeg.wasm.
FAQ
Is this phase invert tool free?
Yes. Anonymous users get 5 free uses per day across AudioKit's free tools — no account needed. A use is only counted when you run the inversion; loading the file and A/B-ing the result is free. AudioKit Premium removes the daily limit.
Is my audio file uploaded to a server?
No. The file is decoded, inverted and re-encoded entirely in your browser with ffmpeg.wasm and never leaves your machine. The only network call is a tiny anonymous counter that tracks your daily free quota.
Which audio formats are supported?
MP3, WAV, FLAC, AIFF, OGG and M4A files up to 500 MB. The inverted file is exported in the same format as the source: lossless stays lossless, lossy formats are re-encoded at high quality.
What is polarity (phase) inversion used for?
Three classic jobs. Fixing phase problems: when two takes of the same source (top/bottom snare mics, a flipped cable, a DI plus a mic) cancel each other, flipping one of them restores the punch. Null tests: play an inverted file against the original — perfect silence proves the two are identical. And cancelling a signal: subtract a known part from a mix by summing it inverted.
Why does the inverted file sound exactly the same on its own?
Because that's the physics: inverting polarity just turns the waveform upside down, and your ears don't perceive absolute polarity on a single signal. The flip only becomes audible when the file is summed with another signal — against the original it produces silence, against a phase-shifted twin it changes the tone. So judge it in context (your DAW), not solo.