The Num Lock Key - What Is It And How Do You Use It?

The Num Lock key allows you to switch between numeric and navigational functions for your numeric keyboard.

The Num Lock key has been a staple of keyboards for decades, ever since IBM introduced it on the first IBM personal computer in 1981. In this guide, I will explain what the Num Lock key does, how it works, and more.

How the Num Lock Key Works on Modern Keyboards

If there is no separate numeric keypad, the Num Lock key may turn certain keys, such as U and O, into navigational keys.

The Num Lock key was first introduced because keyboards were smaller and did not have built-in cursor control keys. The Num Lock key enabled and disabled the numeric keypad and allowed you to use the numeric keys to control cursor behavior, transforming them into arrow keys and other navigational keys.

Today, even though keyboards are larger and have built-in arrow and navigational keys, many keyboards still have a dedicated Num Lock key and function. When it’s on, you will type numbers; when it’s off, you can use the numeric keyboard to navigate your computer.

Where to Find the Num Lock Key on Different Devices

The Num Lock key is usually located on the top-left corner of the numeric keypad. The numeric keypad is typically located on the right side of the keyboard.

If you have a laptop, you may have a smaller keyboard without a dedicated numeric keypad. You may find the Num Lock key in the top row, typically one of the function keys (such as F11). You would have to press the function (FN) key together with that key to activate it.

However, some laptops do not have a dedicated Num Lock key anymore.

How to Turn Num Lock On and Off

To turn Num Lock on and off, simply press the Num Lock key on your keyboard. If the Num Lock key is a function key, you would typically have to press FN together with that key to turn it on and off again. This key may be labeled “Num Lock” or may have a numeric keyboard icon on it.

If there’s no numeric keypad, the Num Lock key may instead toggle certain keys, like O, into navigational keys.

If your computer doesn’t have a Num Lock key, press the Windows key + CTRL + O to open the on-screen Windows keyboard. Once the on-screen keyboard appears, click on the Options key and toggle on “Turn On Numeric Keyboard.” Then, click on OK at the bottom. Once you have enabled the numeric keyboard, you can turn Num Lock on and off using the on-screen keyboard and then use the on-screen keyboard’s navigational keys.

How to Check if Num Lock Is Enabled

Some keyboards have a green indicator light on or above the Num Lock key that shows whether Num Lock is on or off.

Some computers have indicator lights that turn on when Num Lock is enabled. If yours does not have one, the only way to know is to physically test the numeric keypad by clicking on numbers and seeing if they type in numbers or work as navigational keys instead.

How to Turn Num Lock On or Off Permanently

If you find yourself accidentally activating Num Lock, you may want to disable it permanently. Other than physically yanking the key off your keyboard and using complex registry edits that are best reserved for advanced users, the best way to disable it is to install Microsoft PowerToys.

This has a Keyboard Manager utility that allows you to map keys to different functions. By mapping the Num Lock key to something else, you can prevent yourself from accidentally activating it.

Another option is using software such as NumLocker. With this tool, you can set Num Lock to always be on, for example, so you can always type in numbers.

Some computers have a Num Lock setting in the BIOS that allows you to control whether it is enabled or disabled by default when you first boot up your computer.

When You Should Use Num Lock

As I explained earlier, Num Lock used to be more useful, when keyboards were smaller. Nowadays, though, many people still find the need for it, especially if they do a lot of data entry or have calculation-heavy jobs, such as accounting. In that case, Num Lock allows you to ensure you enter numbers when you need to.

Conclusion

I hope this guide helped shine some light on Num Lock and how it works. While it’s mostly a leftover function from older keyboards that hasn’t been removed yet, it’s still useful for some people, especially those who have a lot of data entry to do in their jobs.