Short for Function, Fn is a key found on most laptop keyboards and some desktop computer keyboards. The Fn key performs special functions, such as adjusting the screen's brightness and speaker volume.
Fn key overview
As you can see in the image above, this laptop has an Fn key with a green and blue Fn. Keys with symbols of the same color indicate that their secondary function will be activated by pressing that key with the Fn key. In this example, pressing and holding down the Fn key, along with the up or down arrows, would adjust the laptop screen brightness.
The Fn key should not be confused with the Function keys F1 - F12 found on computer keyboards.
Where is the Fn key found on the keyboard?
On laptop computers, the Fn key is almost always located on the bottom-left side of the keyboard, next to the Ctrl key.
Apple desktop keyboards
Other desktop computers
Most other full-sized desktop computers do not have an Fn key. For those desktop computer keyboards that do have an Fn key, it is often found around the spacebar.
How do I use the Fn key?
With most computer keyboards, the Fn key is used like other modifier keys (e.g., the Shift key). By pressing and holding the Fn key in conjunction with another key that has an Fn function, that function is performed. For example, consider the photo above of the F12 key on an Apple keyboard. This key also has an icon of a speaker, making the F12 key also an audio volume control key. If you press this key, it will adjust the volume of your speakers. But if you hold down the Fn key when you press this key, it will be interpreted as the F12 key. Holding down Fn changes from the default key action to the alternate. You can configure which action is the default, and which action is the alternate, in the keyboard section of your System Settings.
On desktop computer keyboards with an Fn key that lights up when enabled, you need to make sure the key is enabled (illuminated) before pressing the corresponding function key. Once the key is illuminated it no longer needs to be pressed, and each function is performed until the fn key is disabled.
My Fn key does not have multiple colors
Not all Fn keys are color coded. For computers with a white or black Fn key, it still performs the same function and can be pressed in combination with other keys that have pictures on them. For example, pressing the Fn key and a key with a sun on it should adjust the brightness. Pressing the Fn key and a key with a crescent moon should put the computer to sleep.
What functions can the Fn key perform?
The functions available to the Fn key all depend on the computer manufacturer and the type of keyboard. Below is a list of some of the common functions this key can be used to perform.
- Turn up and down brightness on the display.
- Turn up and down the volume.
- Mute the volume.
- Control media functions such as play, pause, fast forward, and rewind.
- Switch between windows.
What if my keyboard does not have an Fn key?
If your computer did not include a keyboard with the Fn key, it has no alternate functions on those keys. You may consider upgrading your keyboard to a different model, such as a multimedia keyboard.
Why does the Fn key not work?
For the Fn key and the function key to work, it must be supported by the computer and device. For example, if you are pressing the Fn key and the brightness key to increase the brightness, it only works on the laptop screen and not an external monitor connected to a laptop. The same goes for special functions, such as opening a browser window, printer, and audio controls.
On desktop computer keyboards with an Fn key that lights up when enabled, you need to make sure the key is enabled (illuminated) before pressing the corresponding function key.
If you are trying to use an Fn key to perform a function that has worked in the past and it no longer works, there may be a problem with the drivers or the actual hardware in the computer.