Summary

This guide helps you troubleshoot and resolve: Screen brightness adjustment. Follow the steps below to fix the issue.

Common Causes

Screen brightness adjustment

Quick Ways to Adjust

Method 1: Keyboard Shortcuts

Most laptops have dedicated brightness keys on the top row of the keyboard. The exact keys vary by manufacturer, so look for a sun icon (usually a larger sun for increase and a smaller sun for decrease):

• Common keys: F1/F2, F5/F6, F11/F12, or F14/F15
• Function key: You may need to hold Fn + the brightness key together
• Manufacturer examples: Dell often uses F11/F12, HP uses F2/F3, Lenovo uses F5/F6

Method 2: Quick Settings (Fastest)

1. Click the date and time in the bottom-right corner of the taskbar.
2. The Quick Settings flyout will open.
3. Click the brightness icon (sun symbol) to open the brightness slider, then drag it left to dim or right to brighten. You can also click the percentage to cycle through preset levels (0%, 25%, 50%, 75%, 100%).

Method 3: Settings App

1. Press Win + I to open Settings.
2. Click System > Display.
3. Under Brightness & colour, drag the Brightness slider left to dim or right to brighten.
4. If you have multiple displays, scroll down and select each monitor to adjust it individually.

Method 4: Night Light

Night Light reduces blue light by adjusting the colour temperature of your display, which can make the screen easier on the eyes in low-light conditions. It does not change the actual brightness level.

1. Press Win + I to open Settings.
2. Click System > Display > Night light.
3. Toggle Use Night light on.
4. Click Night light settings to adjust the Strength slider (warmer = more yellow tint).
5. Optionally, schedule Night Light to turn on automatically from sunset to sunrise.

For External Monitors

Using the Monitor's Physical Buttons

Most external monitors have physical controls on the front, side, or bottom edge:

1. Press the Menu or Settings button on the monitor.
2. Navigate to Brightness (sometimes under Picture or Image).
3. Adjust using the arrow keys or +/- buttons.
4. Press Menu or Exit to save and close.

Using Windows for External Monitors

Some external monitors support DDC/CI, which allows Windows to adjust brightness directly. This is not available on all monitors.

1. Press Win + I to open Settings.
2. Click System > Display.
3. Scroll down and select your external monitor from the Rearrange your displays diagram.
4. Adjust the Brightness slider if it appears.

Auto-Brightness (Laptops)

Some laptops include an ambient light sensor that can automatically adjust brightness based on your surroundings. This option only appears on devices with a compatible sensor.

1. Press Win + I to open Settings.
2. Click System > Display.
3. Under Brightness & colour, toggle on Change brightness automatically when lighting changes.

Tips for Comfort

• Too bright at night? Lower brightness to around 30–40% and enable Night Light.
• Can't see outdoors? Increase brightness to maximum and disable Night Light.
• Eye strain? Try lowering brightness below 50%, enable Night Light, and take regular screen breaks.
• Battery saving? Lowering brightness is one of the most effective ways to extend laptop battery life.

Troubleshooting

Brightness Slider Is Greyed Out or Missing

This is a common issue, usually caused by outdated or missing display drivers:

1. Right-click the Start button and select Device Manager.
2. Expand Display adapters.
3. Right-click your display adapter and select Update driver.
4. Choose Search automatically for drivers.
5. Restart your computer when prompted.

If the issue persists, check for Windows updates by following How to update Windows, or visit your laptop manufacturer's website to download the latest display driver.

Brightness Controls Not Working

• Remote sessions: Brightness controls may not work when connected via Remote Desktop, Citrix, or some virtualisation platforms. Adjust brightness on the local machine before connecting.
• Docking stations: Some docking stations pass through brightness controls differently. Try adjusting brightness directly on the laptop screen first.
• Adaptive brightness override: Some manufacturer utilities (such as Lenovo Vantage or Dell Power Manager) can override Windows brightness settings. Check these apps if brightness keeps reverting.
• Power Options: Open Control Panel > Power Options > Change plan settings > Change advanced power settings. Look for Display > Display brightness and Enable adaptive brightness. Disabling adaptive brightness here can prevent unwanted automatic changes.

External Monitor Not Detected

If your external monitor isn't appearing in Display settings, see Monitor/display not showing for step-by-step troubleshooting.

Need to Capture a Brightness Issue?

If you need to send a screenshot of the issue to support, see How to take a screenshot.

Still Having Issues?