Hertzlight collects nothing.

The app

Hertzlight listens to the audio you choose, whatever your Mac is playing, one app, or a microphone, turns it into bar heights sixty times a second, and throws the sound away. Nothing is recorded, nothing is stored and nothing is sent anywhere.

• There's no account to make and nothing to sign in to.
• There's no analytics, no crash reporting and no advertising. The app makes no network connections.
• Your settings, such as the skin, the source and where the window sits, are kept on your Mac in the app's own preferences. That's the only thing it writes.
• The microphone is used only if you choose it as the source, and only while the app is running.
• If you turn on Hertzlight Camera, the display is sent to video-call apps through a macOS camera extension. With the webcam layout it reads your webcam only to draw the display over it, live, and never records it.

The iPhone app works the same way with the microphone.

This website

The site sets no cookies for visitors and runs no analytics. It's hosted on Cloudflare, which handles requests the way any web host does.

Questions

Email support@hertzlight.com.

This policy was written on 23 October 2026 and applies to Hertzlight for Mac, Hertzlight for iPhone and hertzlight.com. If it changes, the change and its date will appear here.