According to global population data, the world now has approximately 8.2 billion people. It’s difficult to say exactly how many of them use a keyboard—but the number must be extremely high.
If you’re an everyday user or someone who regularly uses a keyboard, have you ever asked yourself: what do keyboard Function Keys actually do?
Imagine this as a dinner-table question: the first person to answer doesn’t have to do the washing up!
Yet on a serious note, Function Keys (F1–F12) are among the most under‑used keys by most users. Even though I work in the industry, I rarely used them—aside from Print Screen. That struck me as odd. If a customer had asked, I’d have felt pretty embarrassed.
That was the moment I decided to find out: what do keyboard Function Keys actually do?
So I set out to answer the question: what do keyboard Function Keys actually do—discovering how these F‑keys work in operating systems, everyday software, and pro applications. In doing so, I realised how underutilised they really are, and how much more useful they could be when understood properly.
| Key | Windows / Common Apps | macOS (Default Apple behavior) |
|---|---|---|
| F1 | Opens Help in most programs; Windows + F1 opens support; in Excel: Alt + Shift + F1 creates new worksheet. Also used to enter BIOS setup. | Decrease screen brightness. To use F1 as standard, hold Fn or enable “Use F1‑F12 as standard keys”. |
| F2 | Renames selected file/folder; in Excel: edits active cell; in Word: Ctrl + Alt + F2 opens document, Ctrl + F2 shows print preview. Also used for BIOS access. | Increase screen brightness. Press Fn + F2 to use as standard key. |
| F3 | Opens search in Windows/File Explorer or browser; in command-line, repeats last command; in Word, Shift + F3 toggles case; in macOS: opens Mission Control. | Shows Mission Control (overview of open apps). |
| F4 | Alt + F4 closes application; Ctrl + F4 closes document/tab; in Explorer/browser: focuses address bar; repeats last command in Word. May enter BIOS. | Opens Launchpad (app launcher) or Dashboard (depending on macOS version). |
| F5 | Refreshes browser or file view; in Word: opens Find & Replace; in PowerPoint: starts slideshow (F5 starts, Shift + F5 from current slide). | Decrease keyboard backlight brightness (on compatible Macs); behaves as hardware control unless Fn locked. |
| F6 | Moves cursor to address bar in browsers; in Word: Ctrl + Shift + F6 switches documents. Occasionally hardware control on some laptops. | Increase keyboard brightness (if supported hardware). Otherwise hardware media function unless Fn toggled. |
| F7 | Launches spell/grammar check in Word/Outlook; in Word: Shift + F7 opens thesaurus; in Firefox: enables caret browsing. | Control media: skip back one track. Available as hardware control by default. |
| F8 | Used at boot to enter Safe Mode; in Excel: enables extend-select mode; in Word: selects text range; in macOS: shows workspace thumbnails. | Play/Pause media. Default hardware control unless Fn mode changed. |
| F9 | Refreshes fields in Word; in Outlook: Send/Receive email; in Excel: recalculates formulas; Quark toolbar; in macOS: Mission Control (via Fn+F9). | Skip forward/media next track (default). Use Fn to access standard F9 if modified. |
| F10 | Activates menu bar; Shift + F10 opens context menu; in Word: Ctrl + F10 maximize/minimize; may enter BIOS or recovery tools. | Mute/unmute audio. Default hardware control. |
| F11 | Toggles Full‑Screen mode in browsers; Shift + F11 adds new sheet in Excel; shows desktop in macOS; and may access recovery on boot. | Volume down (default). Use Fn to send standard F11. |
| F12 | Opens Save‑As in Word; Shift + F12 saves; Ctrl + F12 opens document; Ctrl + Shift + F12 prints; opens developer tools in browsers; may access boot options or recovery. | Volume up (default hardware control). Press Fn to send standard F12. |
Additional Behavior Details
- Fn key: On laptops and multimedia keyboards, holding Fn switches the F‑keys between their standard functions and hardware/media controls (like brightness, volume).
- Fn Lock: Some keyboards include a toggle (e.g. Fn + Esc or BIOS setting) that locks the F‑keys to always work as standard function keys without needing to hold Fn each time.
- macOS customization: In macOS settings you can choose to use the F‑keys as standard or as media keys. If the standard behavior is enabled, you must hold Fn to change brightness, volume, etc.
At a Glance
- F1–F12 keys are standard shortcuts across Windows and applications (help, search, refresh, save‑as, etc.).
- On Mac hardware, they perform hardware controls (brightness, volume, media) by default.
- Use Fn or Fn Lock to toggle between standard F‑key functionality and hardware/media controls.
- Many productivity apps (like Microsoft Office, PowerPoint, Excel) and development environments make extensive use of F‑keys with modifiers.
