How to remove clicks and clean up audio in Audacity

Work from the edit to the sound: cut mistakes and ums first, fix clicks, then remove hum and reduce noise, and set the volume last. Volume changes make everything else louder, including problems you haven't fixed yet.

Effect, Noise Removal and Repair, Click Removal targets sharp, short spikes. It was designed for vinyl crackle, so on mouth clicks start with a low threshold and listen. For a single obvious click, zoom right in, select just the click (a few milliseconds) and use Effect, Noise Removal and Repair, Repair, which redraws that tiny section from the audio around it. Repair only works on very short selections.

Audacity has no automatic filler word removal. You find each um by ear or by looking at the waveform, select it and press Delete. Cut at a quiet point between words, and zoom in so you don't clip the start of the next word. On a 30 minute recording this is the step that takes longest.

Don't delete every breath; it sounds unnatural. Select loud breaths and lower them with Amplify set to a negative value, or use the Envelope tool. For long gaps, Effect, Noise Removal and Repair, Truncate Silence shortens every pause over a length you choose.

Most of this cleanup is faster on a transcript than on a waveform. In Hilite, filler word removal finds every um, silence removal tightens long pauses, text-based editing cuts mistakes like a document, and AI enhancement handles the noise.