What Fn Lock does and why you might want to turn it off

Fn Lock is a toggle that changes what your function keys (F1 through F12) do. When Fn Lock is on, pressing F5 might open a search box instead of refreshing your page. When it's off, F5 refreshes like you expect. Some keyboards ship with Fn Lock turned on by default, which surprises people who are used to function keys working one way on every other device they own.

Whether you want Fn Lock on or off depends on what you do. If you use keyboard shortcuts in your work software — F4 to repeat an action in Excel, F7 to check spelling in Word, F11 to go fullscreen — you probably want Fn Lock off so those keys work as written. If you mostly use the media controls (volume, brightness, play/pause) that sit on top of the function keys, you might prefer Fn Lock on so you can reach them without holding Fn.

The catch: how you turn Fn Lock off varies wildly by keyboard brand and model. There is no single switch that works everywhere. This guide covers the most common methods.

Key Takeaways

  • Fn Lock toggles whether your F1–F12 keys act as function keys or as media controls, and the default setting varies by keyboard manufacturer.
  • Most mechanical and gaming keyboards have a physical Fn Lock key or a key combination (often Fn + Esc or Fn + a specific key) that toggles it.
  • Laptop keyboards usually toggle Fn Lock through a key combination, often Fn + Esc, though some brands use Fn + a different key.
  • If your keyboard has software, check the manufacturer's control panel — it may have an Fn Lock setting you can change there instead of hunting for a physical key.
  • Some keyboards remember your Fn Lock choice; others reset it every time you restart, so you may need to turn it off repeatedly.

How to toggle Fn Lock on a mechanical or gaming keyboard

Gaming and mechanical keyboards often have a dedicated Fn Lock key or a key combination printed right on the keyboard. Look for a key labeled "Fn Lock" or a key with an Fn symbol and a small lock icon. Press it once to toggle Fn Lock on or off. Some keyboards show a light or indicator when Fn Lock is active.

If there is no dedicated Fn Lock key, try the most common combination: hold Fn and press Esc. This works on many Corsair, SteelSeries, Razer, and Logitech keyboards. Other brands use Fn + a different key — check the top row for a key with a lock icon or look at the manual that came with your keyboard. Fn + F12, Fn + Pause, or Fn + Scroll Lock are also common on some models.

After you press the combination, the function keys should behave differently. Test by pressing F5 — if your browser refreshes, Fn Lock is off. If a media app opens or nothing happens, Fn Lock is still on.

How to toggle Fn Lock on a laptop keyboard

Laptop keyboards almost never have a dedicated Fn Lock key. Instead, look for a key combination, usually Fn + Esc. On some Dell, HP, and Lenovo laptops, this is Fn + Esc. On MacBooks, there is no Fn Lock toggle — the function keys always act as media controls by default, and you hold Fn to use them as F1–F12.

If Fn + Esc does not work on your laptop, check the manual or the manufacturer's support site for your specific model. Dell, HP, Lenovo, ASUS, and Acer all use slightly different key combinations. You can also try Fn + the key with a lock symbol if one is printed on your keyboard.

Laptop Fn Lock settings often do not persist after a restart, so you may need to toggle it again each time you turn on your computer. If you use function keys constantly, this can become annoying — in that case, check whether your laptop manufacturer offers a BIOS or firmware setting that lets you change the default behavior permanently.

Using keyboard software to change Fn Lock settings

If your keyboard came with software — Corsair iCUE, Logitech G Hub, Razer Synapse, SteelSeries Engine, or similar — open that program and look for an Fn Lock or Function Keys setting. The exact name and location varies, but it is usually in a section called "Key Mapping", "Keyboard Settings", or "Advanced".

Changing Fn Lock through software has an advantage: the setting usually sticks even after you restart, unlike a physical key toggle on some keyboards. You can also remap individual function keys if you want F5 to do something different from the default.

If you do not have the software installed, visit the keyboard manufacturer's website, search for your keyboard model, and read the latest version. Most of these programs are free. After you install it, plug in your keyboard (or reconnect it if it is wireless) and the software should detect it.

What to do if Fn Lock keeps resetting

Some keyboards, especially budget models and older laptops, do not remember your Fn Lock choice after you shut down. Every time you restart, Fn Lock goes back to the factory default. This is usually a hardware limitation — the keyboard does not have enough memory to store settings.

If this happens to you, your options are limited. First, check whether the keyboard has software that can override this behavior — some do. Second, look in your laptop's BIOS or firmware settings (usually accessed by restarting and pressing F2, F10, Del, or Esc during startup, depending on the brand). Some laptops let you set a default Fn behavior there, and that setting will persist.

If neither of those works, you are stuck toggling Fn Lock manually each time you restart. If you use function keys heavily, this might be a reason to upgrade to a keyboard with better software support or a mechanical keyboard that remembers settings in its own memory.

Fn Lock on external keyboards connected to a Mac

Apple keyboards and most third-party keyboards connected to a Mac work differently. On a Mac, the function keys (F1–F12) are set to media controls by default — F1 and F2 adjust brightness, F11 and F12 adjust volume, and so on. To use them as actual function keys in your software, you hold Fn while pressing them.

You can reverse this behavior in System Settings. Go to System Settings > Keyboard > Function Keys, then choose your keyboard from the list and toggle "Use F1, F2, etc. as standard function keys". After you do this, F5 will refresh your browser without holding Fn, and you will hold Fn to access brightness and volume controls instead.

This setting applies to each keyboard separately, so if you use both an external keyboard and your MacBook keyboard, you can set them differently. The setting persists until you change it again.

Frequently Asked Questions

Why does my keyboard have Fn Lock on by default?

Manufacturers assume most users want quick access to media controls (volume, brightness, play/pause) without holding an extra key. Fn Lock on makes those controls the primary function. If you use function keys for work, you can turn Fn Lock off and hold Fn instead when you need media controls.

Will turning off Fn Lock break anything?

No. Turning off Fn Lock just changes what the keys do — it does not damage the keyboard or your computer. You can toggle it back on anytime. The only downside is that you will need to hold Fn to access media controls if your keyboard has them printed on the function keys.

My keyboard does not have an Fn key at all. Can I still use function keys?

Yes. Some keyboards, especially compact or laptop-style ones, do not have a physical Fn key printed on them, but the function still exists in the firmware. Try Fn + Esc or check the manual. If your keyboard truly has no Fn key, the function keys (F1–F12) should work normally without any toggle needed.

Do I need to turn off Fn Lock on both my keyboard and my laptop?

No. Fn Lock is a setting on each individual device. If you have an external keyboard connected to a laptop, you can turn Fn Lock off on the keyboard and leave it on (or change it) on the laptop separately. They do not affect each other.

What if I cannot find the Fn Lock key combination for my keyboard?

Check the manual that came with your keyboard or visit the manufacturer's support website and search for your model number. You can also try common combinations: Fn + Esc, Fn + F12, Fn + Pause, or Fn + the key with a lock symbol. If the keyboard has software, the Fn Lock setting is usually there instead of a physical key.