Circadian display control for Mac

Your screen
follows the sun.

Local Sun recreates the rhythm of outdoor light through your display, changing blue light and brightness when the sky does.

Stop asking your circadian rhythm to ignore sunset.

Get the release notice

macOS release pending Apple developer approval

01
Local solar model Daylight through astronomical night
02
Software brightness Color and luminance move together
03
Private by default No account, tracking, or cloud

On-device solar model · no account · no tracking

Try the shortcut ⌘
Influence 0%
Local Sun influence 0%

The method

Outdoor timing, translated to a display.

  1. 01

    Calculate the local sun. Latitude, longitude, date, and time determine current solar elevation.

  2. 02

    Set a melanopic target. Blue-light contribution falls through civil, nautical, and astronomical twilight.

  3. 03

    Move color and brightness together. A software display transform follows that target while Command + brightness sets its influence.

Local Sun models the timing and relative melanopic direction of outdoor light. Absolute outdoor spectrum and eye-level illuminance require calibrated hardware and are not claimed.

Privacy

Your location stays on your Mac.

Local Sun uses location only to calculate the sun's current position. Coordinates and preferences are stored locally. There is no account, analytics SDK, advertising SDK, tracking, or cloud database.

Accessibility permission is used only to detect and handle brightness keys. Local Sun does not read, record, store, or transmit typed text.

Support

Direct help from the developer.

Local Sun requires macOS 13 or later, Location access for its solar model, and Accessibility access for global keyboard control.

Email support