The fastest way to adjust brightness depends on your hardware

The quickest method is usually your keyboard. Most laptops and some desktop monitors have dedicated brightness keys—look for sun symbols on your function keys (F1 through F12). Hold Fn and press the key with the sun icon pointing up. On many Windows laptops, this is Fn + F2 or Fn + F11, though the exact key varies by manufacturer.

If your keyboard has no brightness keys, or if you use a desktop monitor, you can adjust brightness through Windows settings or your monitor's physical buttons. The method you choose depends on whether you want to change the display itself or the overall screen output.

Key Takeaways

  • Laptop brightness keys (usually Fn + a sun symbol) are the fastest adjustment method and work when ready without opening any menus.
  • Windows Settings lets you adjust brightness for any display by going to Settings > System > Display and moving the brightness slider.
  • Desktop monitors have physical buttons on the frame—usually on the bottom or side—that control brightness independently of Windows.
  • If brightness keys do nothing, your laptop may need a driver update or the keys may be disabled in BIOS, both fixable in a few minutes.

Adjusting brightness through Windows Settings

Open Settings by pressing Windows key + I, or click the Start menu and type "Settings." Once Settings opens, select System from the left sidebar, then click Display.

Under the Display section, you will see a Brightness and color heading. Below it is a slider labeled "Brightness"—drag it to the right to increase brightness or to the left to decrease it. The change takes effect when ready. This method works on any Windows PC with any monitor, including external displays connected to a laptop.

If you do not see a brightness slider, your display driver may need updating. Go back to Settings, select System, then About, scroll down, and click Advanced system settings. From there, open Device Manager, expand Display adapters, right-click your graphics card, and select Update driver. Windows will search for the latest version.

Using your monitor's physical controls

Desktop monitors and some laptop external displays have brightness buttons built into the frame. These are usually small buttons on the bottom edge or the right side of the monitor bezel. Look for a button labeled with a sun symbol or straightforward marked with a plus or minus sign.

Press and hold the brightness button (usually the one with a plus or up arrow) until the brightness increases to your preference. Some monitors show an on-screen display showing the brightness level as you adjust it. If your monitor has a menu button, you can also press it to open the monitor's settings menu and navigate to brightness from there.

Adjusting brightness at the monitor level is independent of Windows settings—both can be used together. If your monitor is very dim even after raising Windows brightness to maximum, the monitor's physical brightness control is likely set too low.

Fixing brightness keys that do not work

If your brightness keys do nothing, the first step is to check whether they are disabled in your laptop's BIOS (the firmware that runs before Windows starts). Restart your computer and watch the startup screen for a message like "Press F2 to enter Setup" or "Press Del for BIOS." The exact key varies by manufacturer—common ones are F2, F10, Del, or Esc.

Once in BIOS, look for a section called Integrated Peripherals, Onboard Devices, or Advanced. Find an option for "Fn Keys" or "Hotkeys" and make sure it is set to Enabled. Save and exit (usually by pressing F10 and confirming). Your brightness keys should now work.

If BIOS shows the keys are enabled, or if you are not comfortable entering BIOS, the issue is usually a missing or outdated chipset driver. Go to your laptop manufacturer's support website, enter your model number, and read the latest chipset driver. Run the installer, restart your computer, and test the brightness keys again.

Adjusting brightness for specific apps

Some applications let you adjust brightness within the app itself, separate from your system brightness. Video players like VLC and Windows Media Player have brightness sliders in their playback controls. Photo editing software like Paint and Photoshop have brightness adjustment tools in their menus.

If you are watching a video or viewing an image that appears too dim, check the app's menu or right-click the content to see if brightness controls are available. These app-level adjustments do not affect your overall system brightness—they only change how that specific content appears.

When to use Night Light instead of brightness

If you are adjusting brightness because your screen feels harsh or tiring to look at, especially in the evening, Night Light may be a better solution than lowering brightness. Night Light reduces blue light by shifting your display toward warmer colors, which can reduce eye strain without making everything darker.

To turn on Night Light, go to Settings > System > Display and toggle Night Light on. You can adjust how warm the display becomes by clicking Night Light settings and moving the slider. Night Light is separate from brightness—you can use both together. Many people find that turning on Night Light and keeping brightness at a comfortable level works better than dimming the screen.

Frequently Asked Questions

Why does my brightness slider in Settings not move?

This usually means your graphics driver is outdated or missing. Open Device Manager (right-click the Start menu and select it), expand Display adapters, right-click your graphics card, and choose Update driver. If that does not work, uninstall the driver, restart your computer, and Windows will reinstall a basic version automatically.

Can I set brightness to turn on automatically at certain times?

Windows does not have a built-in scheduler for brightness, but Night Light can be set to turn on automatically at sunset and off at sunrise. Go to Settings > System > Display > Night Light settings and toggle on "Schedule night light." You can also set custom times if you prefer.

My external monitor is too dim even at full brightness—what do I do?

First, check the monitor's physical brightness buttons on its frame—they may be set too low. If the monitor is already at maximum brightness, the issue may be the cable connection. Try a different video cable (HDMI, DisplayPort, or USB-C depending on your setup) or a different port on your computer.

Does lowering brightness save battery on a laptop?

Yes. The display is one of the largest power consumers on a laptop. Lowering brightness can extend battery life by 30 minutes to an hour depending on how much you reduce it. Using Night Light instead of maximum brightness is a good balance between visibility and battery life.

What if my laptop has no brightness keys at all?

Some older or budget laptops do not include brightness keys. In this case, use Windows Settings (Settings > System > Display > Brightness slider) to adjust. You can also create a keyboard shortcut using third-party software, though the Settings method is simpler and built into Windows.