Before you panic about a keyboard repair: on almost every MacBook, "Caps Lock not working" turns out to be the delay Apple built in on purpose, a settings change, or an app grabbing the key. True hardware failure is the rare case. Work through these in order and you will know which one you have in a couple of minutes.
First: the 10-second test
Open System Settings > Keyboard > Keyboard Shortcuts > Modifier Keys and confirm Caps Lock Key is set to "Caps Lock" (not "No Action" or remapped to Control/Escape). Then open TextEdit, press and hold Caps Lock for a beat, and watch the little light on the key. If the light comes on and letters go uppercase, nothing is broken - keep reading the delay section. If the light never comes on at all, jump to the hardware section.
The 6 fixes, fastest first
- Press and hold, do not tap. Since macOS Sierra, Apple added a deliberate short delay so a stray brush of the key does not shout your whole sentence. A quick tap often does nothing - hold it about a third of a second. This is by far the most common "broken Caps Lock."
- Check the Modifier Keys mapping. System Settings > Keyboard > Keyboard Shortcuts > Modifier Keys. If Caps Lock is set to No Action, Control, Escape, or Command, that is why nothing happens. Set it back to Caps Lock. (If you have more than one keyboard connected, each one has its own mapping - set the right device at the top.)
- Restart the Mac. A stuck Caps Lock that will not turn off, or a light that is on while typing stays lowercase, usually clears with a reboot that resets the keyboard controller.
- Rule out a stuck key. If the key feels mushy, half-pressed, or gritty, power down and gently clean around it (see our MacBook cleaning guide). A crumb under the keycap can hold the switch down.
- Test in another user or Safe Mode. Create a second user account (System Settings > Users & Groups) or boot into Safe Mode. If Caps Lock behaves there, a login item, remapping app (Karabiner, BetterTouchTool), or accessibility setting on your main account is intercepting the key.
- Check Accessibility. System Settings > Accessibility > Keyboard. Slow Keys and Sticky Keys change how modifier keys register and can make Caps Lock feel dead or stuck. Turn them off unless you use them on purpose.
Caps Lock light on but still typing lowercase (or the reverse)
This split - light and behavior disagreeing - is almost always software, not the switch. Reboot first. If it persists, the culprit is usually a remapping utility or a per-app setting; test in a fresh user account to confirm. A hardware switch that is truly failing tends to give you no light and no uppercase together, not one without the other.
Caps Lock stuck ON and will not turn off
Hold the key firmly for a full second to force the toggle, then reboot. If it is still locked after a restart and a clean login, and pressing it does nothing in every app, that points at the physical switch - move to the next section.
When it really is hardware
If the light never lights, the key feels dead or physically stuck, and it fails in Safe Mode and a second user account, the switch under the key has failed. On 2015-2019 butterfly-keyboard MacBooks this is a known, widespread failure - a single dead or sticky key often means the whole keyboard is on its way out. Apple ran a free Keyboard Service Program for those models, but it has largely aged out of coverage. See our full MacBook keyboard not working and keys repeating or double-typing guides for the complete repair-or-replace decision.
Dead switch? Get a number before you pay for a repair
On a butterfly-keyboard MacBook, an out-of-warranty keyboard repair means replacing the entire top case - often several hundred dollars, more than the machine is worth. Before you book that, it is worth seeing what the MacBook is worth as-is. We buy MacBooks with broken keyboards and put that toward a fully working refurbished one - Apple clearance MacBooks start at $450. Skip the repair, keep the money.
Related guides
- MacBook keyboard not working? Every fix in order
- MacBook keys repeating or double-typing
- MacBook keyboard backlight not working
- All guides
Frequently Asked Questions
Why does my Caps Lock only work if I hold it down?
That is intentional. Since macOS Sierra, Apple added a short activation delay to Caps Lock so a light accidental touch does not flip everything to uppercase. Press and hold the key for about a third of a second rather than tapping it - it is working exactly as designed.
How do I turn off the Caps Lock delay on a Mac?
Apple does not expose a built-in toggle for the delay. You can remap Caps Lock in System Settings > Keyboard > Keyboard Shortcuts > Modifier Keys, but removing the delay itself requires a third-party utility such as Karabiner-Elements. For most people, learning to hold the key briefly is simpler.
Why is the Caps Lock light not turning on?
First confirm Caps Lock is not remapped to No Action or another key in Modifier Keys. If the mapping is correct, reboot. If the light still never lights and the key does nothing in Safe Mode and a second user account, the switch has failed - that is a hardware repair.
How much does it cost to fix a stuck Caps Lock key?
On modern MacBooks the keyboard is part of the top case, so a single failed key usually means replacing the whole assembly - frequently several hundred dollars out of warranty. On older machines it is often not worth it; selling the MacBook toward a working one is usually the better call.
Can a Caps Lock problem be caused by an app?
Yes. Remapping tools (Karabiner, BetterTouchTool), some games, and remote-desktop sessions can intercept Caps Lock. If it behaves normally in a fresh user account or Safe Mode but not on your main login, an app or login item is the cause - not the keyboard.