Night Shift vs f.lux on Mac: Which to Use in 2026

Night Shift is enough for most Mac users: it’s built in, schedules itself, and warms the screen with one slider. Choose f.lux if you want stronger warmth timed to your bedtime, Kelvin presets, or the option to switch it off for one app. Neither fixes eye strain; breaks do.

TL;DR

• Night Shift: System Settings › Displays › Night Shift. It has a Custom or Sunset to Sunrise schedule, “Turn on until tomorrow” and one colour temperature slider. It’s built into macOS.
• f.lux: a free menu bar app. It runs daytime, sunset and bedtime phases from your wake time, has presets down to 1200K, and can be disabled for an hour, until sunrise or for the current app. It also has Movie mode and Darkroom.
• f.lux’s last Mac release is 42.2, dated 1 June 2023, with native Apple Silicon and DCI-P3 support. There’s been no Mac release since.
• Pick one. Running both stacks two tints.
• Eye strain: neither helps, and nor do blue light glasses. 20-20-20 breaks do.

How do Night Shift and f.lux compare?

	Night Shift	f.lux
Price	Built into macOS	Free (donations welcome)
Where you control it	System Settings › Displays, Control Center, Siri	Its menu bar icon
Schedule	Custom times, or Sunset to Sunrise (needs Location Services)	Daytime, Sunset and Bedtime phases from your location and wake time
Warmth control	One slider	Kelvin presets from Ember (1200K) to Sunlight (5500K), plus custom colours per phase
Turn it off for one app	No	Yes (“For current app”)
Temporary modes	”Turn on until tomorrow”	Disable for an hour or until sunrise, Movie mode (2.5 hours), Darkroom
Dark mode link	Auto appearance follows the Night Shift schedule	Optional “Dark theme at sunset”
Latest version	Ships with macOS	42.2, 1 June 2023

Sources: Apple’s Use Night Shift on your Mac and Change Night Shift settings, and f.lux’s Mac quickstart, FAQ and update feed.

True Tone is a different feature. It adjusts the colour and intensity of your display to match the light in the room, and Apple says you can use True Tone and Night Shift at the same time. It isn’t a blue light filter.

How do you turn on Night Shift on a Mac?

1. Choose Apple menu › System Settings, then click Displays in the sidebar. You may need to scroll down.
2. Click Night Shift.
3. Open the Schedule pop-up menu:
   • Custom: choose when Night Shift starts and ends.
   • Sunset to Sunrise: your Mac uses your location to work out when it’s night, so Location Services must be on.
4. To turn it on right now, use Turn on until tomorrow. Night Shift stays on until the next day or until you turn it off.
5. Drag the colour temperature slider. Warmer settings show more yellow and less blue.

The quicker switch is Control Center › Display › Night Shift, or ask Siri. These steps come from Apple’s Shift to warmer colors on your Mac and Set the color temperature guides for macOS 27.

Two things to know. Night Shift needs macOS 10.12.4 or later and a Mac from 2012 or later (a Mac Pro from 2013 or later), and Apple says it depends on the characteristics of an external display how well it works there. And if your Appearance is set to Auto, your Mac switches to dark mode while Night Shift is on (Apple).

What does f.lux add?

f.lux does the same basic job with more control. Everything below comes from f.lux’s Mac quickstart, Mac update page and FAQ:

• A day in three phases. Daytime leaves your screen at 6500K by default. Sunset covers the evening, and Bedtime moves with your wake time. You set your location with Location Services, a city name, a US postal code or map coordinates.
• A wider colour range. The FAQ lists Kelvin presets from Ember (1200K) and Candle (1900K) up to Sunlight (5500K). Presets include Recommended colors, Custom colors, Classic f.lux (3400K at sunset) and Working late. Expanded daytime settings let the daytime slider go down to 1900K.
• Ways to switch it off. You can disable it for an hour, until sunrise or for current app. The last one is the one designers want: your browser shows true colours while your editor stays warm. There’s also a disable for full-screen apps.
• Colour effects. Movie mode lasts 2.5 hours and keeps shadow detail and skin tones. Darkroom removes all blue and green light and inverts colours.
• Sleep extras. A backwards alarm clock tells you how much sleep you’ll get if you go to bed now. Sleep in on weekends shifts Friday and Saturday nights later. Dim on disable makes quick colour checks at night less harsh.

f.lux is also stronger by design. In 2017 its developers argued that Night Shift’s defaults are gentle and remove much less of the “alerting” light than f.lux’s bedtime setting. Those were their own measurements, not an independent test, but the gap in range is real: Night Shift gives you one slider, and f.lux goes down to candle and ember warmth.

Is f.lux still updated for Mac?

Not since 2023. f.lux’s Sparkle update feed (macflux.xml) lists 42.2, dated 1 June 2023, as the latest Mac version. We checked it on 30 September 2026. That release added:

• native support for Apple Silicon
• support for DCI-P3 wide-gamut displays (they used to look “a bit greenish and oversaturated”)
• fixes for full-screen disable on Ventura and for dim on disable
• a Darkroom fix on Apple Silicon

f.lux’s Mac update page adds one limit: after the Ventura fix, full-screen disable works on a single display but not on multiple displays.

It’s still a free download and still does its job. The catch is that the release notes stop at Ventura (macOS 13). If something misbehaves on a newer macOS, there’s no newer build to try, and Night Shift is the fallback.

Should you run both at once?

Pick one. Both tint the whole display, so running both can stack the warmth. When colours look wrong, you then have two apps to check.

• If you choose f.lux: open System Settings › Displays › Night Shift and set Schedule to Off. Leave “Turn on until tomorrow” off too.
• If you choose Night Shift: click the f.lux menu bar icon and choose Quit f.lux. f.lux’s guide says to quit it before you delete the app. If a tint stays after quitting, it says a reboot usually fixes it. If not, remove the f.lux colour profile in Displays settings.
• For colour-accurate work: with f.lux, use “For current app” on your design tool or browser. With Night Shift, switch it off from Control Center while you work.

Do Night Shift or f.lux reduce eye strain?

No. They change the colour of your screen in the evening. Apple frames Night Shift as a sleep aid: “exposure to bright blue light in the evening can affect your circadian rhythms and make it harder to fall asleep” (Apple). Digital eye strain has other causes: hours of close focus, blinking less and glare or brightness that doesn’t match the room. A warmer tint changes none of these. For the research, see screen time and eye health. For setup and habits that help, see developer eye strain prevention.

Even the sleep benefit is modest in the studies so far, which tested iPhones and iPads rather than Macs:

• Melatonin: a Lighting Research Center study found melatonin suppression didn’t differ between Night Shift’s low and high warmth settings. Its conclusion was that changing the colour without lowering the brightness may not be enough (Nagare et al., 2019).
• Sleep: in a trial with 167 young adults, sleep outcomes didn’t differ between using an iPhone with Night Shift, without it, or not using a phone at all. In an exploratory analysis of people who already slept more than 6.8 hours a night, no phone beat phone use with Night Shift (Duraccio et al., 2021).

So if you use either at night, turn the brightness down too. For eye strain, take regular breaks. The 20-20-20 rule means looking at something 20 feet away for 20 seconds every 20 minutes.

Do blue light glasses help?

Not for eye strain. In a double-masked trial, 120 people with eye strain symptoms did a two-hour computer task. Blue-blocking lenses didn’t change signs or symptoms of eye strain compared with clear lenses (Singh, Downie & Anderson, Am J Ophthalmol 2021;226:243-251). A 2023 Cochrane review of 17 trials reached the same conclusion: blue-light filtering lenses may not reduce eye strain from computer use in the short term, and their effect on sleep is uncertain (CD013244.pub2). The full evidence is in screen time and eye health: what the research says.

Can FavTray control Night Shift?

Yes, with a simple on/off switch. FavTray’s Eye Rest timer is free with no limit and reminds you to take 20-20-20 breaks, which is the part that helps with strain. It also has a Night Shift switch on the Eye Rest screens and in Settings › Eye Rest › Night Shift. The switch turns your Mac’s own Night Shift on or off, the same one in System Settings and Control Center. It also picks up changes you make there. It doesn’t set a schedule or the colour temperature, so keep those in System Settings › Displays › Night Shift. On a Mac where FavTray can’t reach Night Shift, the switch doesn’t appear.