Which function key turns up brightness?
On most laptops, the key that raises screen brightness is a top-row function key marked with a sun icon. There is no universal single key across all devices—the exact key varies by brand and model, and you may need to press Fn to activate it. On Apple devices, brightness is commonly controlled by F2; on many Windows laptops the brightness-up key could be F11 or F12 or another top-row key with a sun icon.
Common mappings by platform
Below are representative examples of which function-key commonly controls brightness on several popular brands. Note that keys can vary by model and you may need to press Fn.
- Apple/macOS laptops: brightness up is typically the F2 key on the keyboard (sun icon). You may need to use Fn if your keyboard treats function keys as media controls by default.
- Dell laptops: brightness up is commonly F12 (sun icon) and brightness down is F11 on many models; Fn may be required on some configurations.
- HP laptops: brightness up often uses F2 on the top row; press Fn if necessary depending on your keyboard’s function-key mode.
- Lenovo ThinkPad laptops: brightness up is commonly F9 (often used with Fn, Fn+F9) on many ThinkPads; some models may use F5/F6.
- Asus laptops: brightness up frequently uses F5 on the top row, often with Fn in front of the key to activate hardware brightness control.
- Acer laptops: brightness up commonly uses F6 on the top row, with Fn as needed on some devices.
The exact key can vary by model, so check your device’s keyboard legend or the user manual to confirm the correct brightness-up key for your particular model. If your system uses a Fn-lock, you may need to toggle it off or adjust in the BIOS/UEFI settings.
Alternative methods to adjust brightness (software controls)
If the hardware keys aren’t functioning or you prefer not to use them, you can adjust brightness through the operating system or the display’s own controls. Here are common software methods.
- Windows: Open Settings > System > Display and move the Brightness slider. You can also use the Action Center quick actions to adjust brightness on some devices.
- macOS: Go to System Settings > Display (or System Preferences > Displays) and adjust the Brightness slider there.
- External monitors: Many monitors have physical brightness buttons or an on-screen menu; adjust brightness on the monitor itself if you’re using an external display.
- Driver/firmware updates: Ensure your keyboard and display drivers are up to date, as missing drivers can sometimes disable hardware brightness controls.
These software options provide reliable alternatives if the physical keys are limited or unresponsive. If adjustments still don’t take effect, consult manufacturer support for a deeper hardware check.
Summary
Brightness control hinges on the specific key layout of your device. In practice, expect a top-row function key marked with a sun icon to be the brightness-up control, most commonly F2 on Apple devices and F11 or F12 on many Windows laptops, with Fn often required. When in doubt, consult the device manual or the on-screen display in the OS settings to confirm the exact key and ensure your keyboard’s function-key mode is set correctly.
