What Is a Backlit Keyboard? | Lighted Keys, Explained

A backlit keyboard is any keyboard with built-in illumination beneath or around the keys, designed to improve visibility in low light. You’ll find the feature most often on laptops—business machines, gaming rigs, consumer notebooks, and premium ultrabooks—plus a growing number of external keyboards. The lights sit under or around the keys so the letters and symbols are easier to read in a dark room, on a late flight, or anywhere you don’t want to turn on a bright overhead light.

How Backlit Keyboards Work

Most backlit keyboards use LEDs for their light source. LEDs are efficient, bright, and small enough to fit under a slim laptop keycap, which is why they’ve become the standard. On many models, the backlight isn’t a simple on/off switch—you can adjust the brightness in steps, and some keyboards let you turn it off entirely.

The exact behavior depends on the device. Some Mac laptop keyboards light up automatically when the room gets dark, using the built-in ambient light sensor. Windows laptops, by contrast, put the control in the hands of the manufacturer, so behavior varies from one model to the next.

How to Turn On the Backlight

Turning on a backlit keyboard is usually a function-key press, but the specific key depends on your system.

• Mac laptops: Press the F5 key to decrease brightness or F6 to increase it. On some models you may need to hold the Fn key while pressing either one.
• Macs running Windows via Boot Camp: The same F5 and F6 keys work, and Fn may also be required.
• Windows 11 laptops: On compatible devices, go to Settings > Bluetooth & devices > Keyboard and look for a “Keyboard backlight” option. You may also find a toggle to stop the backlight from dimming automatically when lighting conditions change.

One important distinction: Windows does not guarantee a permanent always-on backlight. The feature is controlled by your laptop’s firmware and the manufacturer’s design, so the settings screen may look different—or be missing entirely—depending on who built your machine.

Common Misconceptions and Limits

The biggest mistake people make is assuming every laptop has a backlit keyboard. Lenovo’s backlit keyboard glossary notes it’s a common feature on business and gaming laptops, but budget and basic models often skip it. And if your keyboard lacks the physical LED hardware, no software setting can add it—this is a hardware feature first, a software feature second.

Another common mix-up: confusing brightness controls with the presence of lighting. A key that shows a sun icon doesn’t guarantee your keyboard is backlit—it may control screen brightness instead. And on some Macs, pressing the backlight keys with Fn held down or not changes the result, so it’s worth checking both ways before assuming the feature is broken.

There’s no serious safety concern with backlit keyboards. The main trade-off is power: the lights draw battery, which is why most laptops dim automatically on battery power or in an energy-saving mode. If your Mac keyboard keeps dimming, check the Energy Saver settings and look for the option to lower keyboard brightness when using energy saver.

If you’re shopping for a new machine and the backlight is essential, it’s worth checking the spec sheet before buying—and if you’d rather not pay the premium for a built-in model, a separate backlit keyboard can plug into any computer. our tested roundup of the best backlit keyboards covers the top picks if you’re ready to compare options.

Apple has documented the backlight feature on its Mac laptops, but the Boot Camp control panel’s keyboard backlight guide makes clear it applies only to certain models—not every Mac. The same holds true across the Windows world, where the option’s presence depends entirely on what the manufacturer built in.