iPhone has a blue light filter called Night Shift, and it works on all recent models

Night Shift is Apple's built-in blue light filter. It reduces the amount of blue light your iPhone screen emits, which can help reduce eye strain in low-light conditions and may make it easier to fall asleep if you use your phone before bed. Night Shift is available on iPhone 5s and newer, and it works automatically or on a schedule you set.

Night Shift does not block all blue light — it shifts the color temperature of your display toward warmer tones (more yellow and red, less blue). This is different from a true blue light blocking filter, which would remove blue wavelengths entirely. For most people, the shift is noticeable but not dramatic.

Key Takeaways

  • Night Shift is built into iOS and turns on from Settings > Display & Brightness > Night Shift on any recent iPhone.
  • You can set Night Shift to turn on automatically at sunset and off at sunrise, or turn it on manually whenever you want.
  • The warmth slider lets you adjust how much the screen shifts toward yellow — stronger settings are more noticeable but may look unnatural in bright rooms.
  • Night Shift works on the iPhone's main display but not on external monitors connected to your phone.

How to turn on Night Shift manually

Open Settings, then tap Display & Brightness. Scroll down and tap Night Shift. Toggle the switch to On. The screen will when ready shift to a warmer color.

You can adjust how warm the screen gets by dragging the slider at the bottom of the Night Shift screen. Moving it to the right makes the filter stronger (more yellow). Most people find a middle setting comfortable for evening use.

To turn Night Shift off, go back to Settings > Display & Brightness > Night Shift and toggle it off, or use Control Center: swipe down from the top-right corner of your screen, press and hold the brightness controls, and tap the Night Shift icon.

How to schedule Night Shift to turn on automatically

In Settings > Display & Brightness > Night Shift, tap Schedule. Toggle on Sunset to Sunrise to have Night Shift turn on automatically when the sun sets in your location and turn off when it rises. Your iPhone uses your location data to calculate these times.

If you prefer a fixed time instead, tap Custom Schedule and set the exact times you want Night Shift to turn on and off. For example, you might set it to turn on at 9 p.m. and off at 7 a.m.

Once a schedule is set, Night Shift will follow it automatically. You can still override it by turning Night Shift on or off manually in Control Center at any time.

Night Shift vs. other blue light options

Night Shift is the only blue light filter built into iOS. Third-party apps that claim to block blue light exist on the App Store, but they work differently than Night Shift — most overlay a colored filter on top of your apps rather than adjusting the display itself. These apps are less efficient because they consume battery and can make text harder to read.

If you use an external monitor with your iPhone (through a USB-C or Lightning connection), Night Shift does not affect that monitor's display. The monitor will show full blue light regardless of your Night Shift setting. You would need to adjust the monitor's own color settings or use the monitor's blue light filter if it has one.

For iPad, Apple offers the same Night Shift feature in Settings > Display & Brightness. Mac computers have a similar feature called Night Shift in System Preferences > Displays.

When Night Shift actually helps

Night Shift is most useful in dim lighting — at night, in a dark room, or in the evening. In bright daylight, the warm shift is barely noticeable and may not feel natural. If you are using your phone in a bright room, turning Night Shift on may make colors look off without providing much benefit.

The research on blue light and sleep is mixed. Some studies suggest that blue light exposure in the evening can delay melatonin production and make falling asleep harder. Other studies find the effect is small or only happens at very high brightness levels. Night Shift is a low-cost option to experiment with if you suspect evening phone use affects your sleep — you can turn it on for a week and see if you notice a difference.

Night Shift will not reduce eye strain from staring at a screen for long periods. Eye strain comes mainly from not blinking enough and from focusing at the same distance for too long. Taking breaks, adjusting your screen brightness to match your surroundings, and positioning your phone at arm's length are more effective for reducing fatigue.

Troubleshooting Night Shift problems

If Night Shift is not turning on automatically on schedule, check that your iPhone has location services enabled. Go to Settings > Privacy > Location Services and make sure it is toggled on. Night Shift uses your location to calculate sunset and sunrise times, so it cannot work without this.

If Night Shift looks too strong or too weak, adjust the warmth slider. The default setting is in the middle — moving it left makes the filter lighter, and moving it right makes it stronger. You can change this at any time without restarting your phone.

If you have an older iPhone (iPhone 5 or earlier), Night Shift is not available. You would need to upgrade to iPhone 5s or newer to use this feature. Older devices do not have the hardware to support the color temperature adjustment.

Frequently Asked Questions

Does Night Shift actually reduce blue light, or does it just make the screen look yellow?

Night Shift reduces blue light by shifting your display's color temperature toward warmer tones. It is not a complete blue light blocker — it is a color adjustment. The yellow appearance is the result of the reduction. Whether this reduction is enough to affect your sleep or eye strain depends on the individual and the research is not conclusive.

Can I use Night Shift during the day?

Yes, you can turn Night Shift on at any time. However, it is most noticeable and useful in dim lighting. During the day or in bright rooms, the warm shift may make colors look unnatural without providing much benefit. You can adjust the strength of the filter to find a setting that works for your environment.

Will Night Shift drain my battery faster?

Night Shift has minimal impact on battery life. The feature adjusts how your display renders colors rather than adding a separate filter or running a background process, so the power draw is negligible. You should not notice a difference in battery life whether Night Shift is on or off.

Does Night Shift work on Face ID or the lock screen?

Night Shift applies to your entire display, including the lock screen and Face ID. When Night Shift is on, the lock screen and all apps will show the warmer color tone. This is why some people turn Night Shift off during the day — the warm tone can make it harder to see colors accurately if you are editing photos or doing color-sensitive work.

Can I set different Night Shift schedules for different times of year?

No, Night Shift uses a single schedule. If you choose Sunset to Sunrise, it adjusts automatically based on your location throughout the year. If you choose Custom Schedule, the same times explore every day. You cannot create different schedules for summer and winter, but the Sunset to Sunrise option handles seasonal changes automatically.