Automatically dim your Mac screen
at night, on a real schedule

How Night Shift's schedule works

Night Shift, found in System Settings → Displays → Night Shift, can run sunset to sunrise or on custom times you set. During that window it shifts the display's color temperature warmer. That is the entire feature: a schedule for one warm slider. It does not dim the screen below the backlight's minimum, and it has no concept of spectral filtering, no FL-41 emulation, no melanopic targeting, nothing built for light-sensitive eyes.

f.lux offers a similar day-and-night schedule with a more adjustable color-temperature curve, and people searching for a flux schedule alternative usually want the same thing Night Shift is missing: a schedule that controls more than warmth. See how the two compare in more depth on Nox vs f.lux.

How Nox scheduling works

Nox schedules the filter two ways, and you pick whichever fits how you work:

• Custom times: set your own on and off times, for example 8 PM to 7 AM, and the filter switches on and off exactly then.
• Sunset to sunrise: the filter turns on automatically at sunset and off at sunrise, tracking the changing sunset time as the seasons shift.

Sunset and sunrise are calculated on-device, using your Mac's approximate location and the standard solar position equations, the same math astronomy uses to compute the sun's angle from latitude, longitude, and date. Nox reads your Mac's approximate location once to seed that calculation and does the rest of the math locally. Nothing about your location is sent anywhere: no server, no account, no network request. It never leaves your Mac.

Whichever schedule you choose drives the same filter stack as the rest of the app, any of the 12 presets, plus dimming, black point, and contrast, not just a single color-temperature slider.

Manual toggle overrides the schedule

Turning the filter on or off yourself, from the menu bar or the global keyboard shortcut, overrides the schedule until the next scheduled transition. Switch it off early if a bright room needs full color for a video call, or turn it on ahead of time on a difficult day. Either way, the schedule quietly resumes at its next transition rather than fighting your override.

No sunset? Nox still runs on schedule

Above the Arctic Circle and below the Antarctic Circle, there are stretches of the year with no sunset or sunrise at all. When Nox cannot compute a sunset or sunrise for your location and date, it falls back to your custom on/off times, so the schedule keeps working instead of silently failing.

Pairs with Pause

A schedule works best with an easy way out of it. Nox's pause lets you suspend the active filter for 15 minutes, an hour, or until morning, then it resumes on schedule automatically. Pause it during a scheduled evening session for color-critical work or a call, and get back to filtered comfort without touching the schedule itself.

What Nox changes on your Mac

Nox is a menu bar app for macOS 14 and later, downloaded as a signed DMG from this site. While running, it writes to the display's gamma tables through the standard macOS display APIs. The schedule and sunset calculations run locally as part of that same process; nothing about your schedule, location, or usage is transmitted anywhere. Nox installs no kernel or system extensions and requires no account. Toggling the filter off or quitting Nox restores your display immediately. To uninstall, quit Nox and move it from Applications to the Trash. Details on data handling are in the privacy policy; support is support@getnoxapp.com.