F9 may refer to any of the following:
1. F9 is shorthand for "Fine," sometimes used in chat communication.
2. The F9 key is a function key at the top of almost all computer keyboards. The key opens Mission Control on an Apple computer. As mentioned below, the F9 key also has other uses depending on the computer and program.
How to use the F9 key
Open the program that uses the key and press F9. If the F9 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 F9.
If when pressing the F9 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 F9, hold down fn, and press F9.
If the FnLk (function lock) is enabled, the keyboard acts as if the Fn key is being pressed until it is unlocked.
Information about the secondary function is found in the below secondary function of the F9 section.
If the F9 key is not working on the keyboard, see: Some keys on my computer keyboard aren't working.
Where is the F9 key used?
The following list is all the locations where the F9 key can be used with information about its use.
Firefox and Edge
The F9 key enters and exits the Reader mode.
Send and receive e-mail in Microsoft Outlook.
Opens the Measurements toolbar in Quark 5.0.
The secondary function of the F9
Each function key has two functions for a laptop and desktop computer keyboard with the Fn key. Unfortunately, there's no standard to what each key uses as its secondary function, so every keyboard is different. Below are keyboards and their secondary function for the F9 key.
- Apple keyboard F9 key
- Cooler Master keyboard F9 key
- Dell keyboard F9 key
- HP (Hewlett-Packard) keyboard F9 key
- Lenovo ThinkPad F9 key
- Logitech keyboard F9 key
- Microsoft Surface F9 key
Apple keyboard F9 key
Cooler Master keyboard F9 key
On Cooler Master desktop keyboards, the F9 secondary function is one of the following options depending on the model.
- With a single-color keyboard backlight keyboard, FN+F9 mutes the audio.
- With a multiple backlight colors (RGB) keyboard, FN+F9 adjusts the repeat rate mode.
Dell keyboard F9 key
HP (Hewlett-Packard) keyboard F9 key
Lenovo ThinkPad F9 key
Logitech keyboard F9 key
On Logitech keyboards with a right triangle and two lines, the F9 key is used to play and pause in supported media players. Logitech keyboards with a line through a speaker on the F9 key mute and unmute the volume.
Microsoft Surface F9 key
Where is the F9 key on my smartphone or tablet?
Related keyboard shortcuts and keys
Below are links to related keyboard shortcuts and individual key pages.