Updated: 12/31/2020 by Computer Hope
The F3 key is a function key found at the top of almost all computer keyboards. The key is most often used to open the find or search feature of a program or operating system. F3 also has other uses depending on the computer and program, as mentioned below.
How to use the F3 key
Open the program that uses the key and press F3. If the F3 key also has an icon on the key, it indicates the key has a secondary function. To use the secondary function, press and hold down the Fn key, and while continuing to hold the key, press F3.
If when pressing the F3 key the secondary function is performed (e.g., mutes audio), the function keys are the secondary function. For example, on an Apple computer, to press F3, hold down the fn key, and press F3.
If the FnLk (function lock) is enabled, the keyboard acts as if the Fn key is being pressed until it is unlocked.
Information about what the secondary function may be is found on the below secondary function of F3 section.
Where is the F3 key used?
The following list is all of the locations the F3 key can be used with information about how it’s used.
Apple macOS X
The F3 on an Apple keyboard opens Mission Control on an Apple computer running the macOS X operating system.
In Windows Explorer, starts the search function.
Windows key+F3 opens the Advanced find window in Microsoft Outlook.
In Microsoft Word, Ctrl+F3 lowercases any highlighted text.
Shift+F3 changes the text in Microsoft Word from upper to lowercase or a capital letter at the beginning of every word.
With Microsoft Windows 7 and earlier pressing F3 when at the Windows desktop opens a window find files.
The F3 button no longer does anything in Windows 10 on the desktop.
Windows command line
In MS-DOS or Windows command line, F3 repeats the last command entered.
Other F3 uses
- In programs not mentioned above, F3 is often used to open up a search or find and sometimes used to find the next search value.
The secondary function of F3
For laptop keyboards and desktop computer keyboards with the Fn key, each function key has two functions. Unfortunately, there’s no standard to what each key uses as its secondary function, so every keyboard is different. Below is a list of different keyboards and their secondary function for the F3 key.
Apple keyboard F3 key
On Apple keyboards, the default fn key primary function opens Mission Control on an Apple computer running the macOS X operating system. Pressing the fn+F3 for the secondary function is F3.
Cooler Master keyboard F3 key
On Cooler Master desktop keyboards, the F3 secondary function is one of the following options depending on the model.
- With a single-color keyboard backlight keyboards, FN+F3 increases the backlight brightness.
- With a multiple backlight colors (RGB) keyboard, FN+F3 adjusts the green color levels.
Dell keyboard F3 key
On Dell laptop keyboards, the F3 key secondary function is to mute and unmute the volume.
HP keyboard F3 key
On Hewlett-Packard laptop keyboards with a brightness or sun icon on the F3 key, the secondary F3 function is increase the screen brightness.
Lenovo ThinkPad F3 key
On the IBM and Lenovo ThinkPad keyboards with a speaker icon next to a plus, the F3 key secondary function is to turn up the volume.
Logitech keyboard F3 key
On Logitech keyboards with an arrow pointing to the left on the key, the F3 key secondary function goes back in an Internet browser.
Microsoft Surface F3 key
On the Microsoft Surface laptops, the F3 key secondary function plays and pauses audio in supported programs (e.g., Windows Media Player).
Below are links to related keyboard shortcuts and individual key pages.
Fn, Function keys, Keyboard, Keyboard terms