Laptop keyboard keys not working: find the cause and fix it

Step 1: test which keys fail

Guessing wastes time. Open the keyboard test (or the laptop keyboard test with an Fn row and no numpad, or the Mac keyboard test), press Start keyboard test and press every key. Each key lights up when the browser receives it. Nothing you type is saved or sent.

The pattern tells you a lot:

• One or two keys never light up: dirt under the key or a worn switch. Go to the cleaning section.
• A whole row or block is dead: often a loose internal cable or a liquid spill. Do the BIOS check below.
• Keys light up but type the wrong character: a layout or language mismatch, not a fault.
• Keys work only when you hold them for a while: Filter Keys (Windows) or Slow Keys (Mac) is on.
• A key types twice: watch the Chatter (double input) panel in the test. Repeated double inputs on the same key point to a worn switch.

Some keys never light up in any browser and that is normal: Fn is handled inside the keyboard, media and brightness keys go to the system, and Print Screen may only report its release on Windows.

F-keys or top row doing the wrong thing: Fn lock

On most laptops the top row has two jobs: F1–F12 and media or brightness actions. Which one you get without holding Fn is a setting, and it is easy to flip by accident.

1. Press Fn + Esc once and try the top row again. Lenovo (IdeaPad and ThinkPad), Dell and many HP models use this combination as an Fn lock toggle; on Lenovo a light on the Esc key shows the state. Some brands use a key with a padlock and "Fn" on it instead.
2. Still wrong after a restart? The default is often set in the BIOS or UEFI setup. HP calls it Action Keys Mode under System Configuration; Dell models list Fn Lock Options under POST Behavior. Lenovo also offers it in the Lenovo Vantage app under Device → Input & Accessories.
3. On a Mac, open System Settings → Keyboard → Keyboard Shortcuts → Function Keys and turn Use F1, F2, etc. keys as standard function keys on or off. Without it, hold fn (or the Globe key) to get the F-key.

Keys slow, ignored or "stuck": Filter Keys and Sticky Keys

Accessibility features change how keys respond, and their shortcuts are easy to trigger by accident. Holding the right Shift for 8 seconds switches on Filter Keys (short presses get ignored); pressing Shift five times switches on Sticky Keys (modifiers stay "held").

Windows 11

1. Press Win + U, or open Start → Settings → Accessibility.
2. Select Keyboard.
3. Turn off Sticky keys, Filter keys and Toggle keys, then test again.

Windows 10

Open Start → Settings → Ease of Access → Keyboard and turn off Use Sticky Keys, Use Filter Keys and Use Toggle Keys.

Mac

1. Open the Apple menu → System Settings → Accessibility → Keyboard and make sure Slow Keys is off.
2. Go to Accessibility → Pointer Control and make sure Mouse Keys is off (with Mouse Keys on, some letter keys move the pointer instead of typing). Option + Command + F5 opens the Accessibility Shortcuts panel where you can switch it off quickly.
3. Caps Lock and Media Eject have a built-in short delay on Mac: hold them a moment longer.

Keyboard typing wrong letters: layout and language

If @ and " are swapped, Y and Z trade places, or letters come out in another alphabet, every key works: the system is using a different layout than the one printed on the keys.

Windows 11 and 10

1. Look at the language icon on the right of the taskbar (for example ENG US). Click it and pick the layout that matches your keys.
2. Win + Space cycles through installed layouts; that is often how they change by accident.
3. To remove a layout you never use: Settings → Time & language → Language & region, open the language’s options and remove the extra keyboard.

Mac

Open System Settings → Keyboard, under Text Input click Edit and turn on Show Input menu in menu bar. Then pick the right layout from the Input menu at the top of the screen.

Our keyboard test matches keys by their physical position and, in Chrome and Edge, can label them with your system layout (Show my system layout). So the test lights the right key even when the layout is wrong: that is the giveaway.

Drivers and updates (Windows)

A broken driver can kill the whole built-in keyboard, typically right after an update.

1. Right-click Start and open Device Manager.
2. Expand Keyboards. A yellow warning sign means Windows has trouble with the device.
3. Right-click the keyboard (often Standard PS/2 Keyboard or HID Keyboard Device) and choose Uninstall device, then restart. Windows reinstalls the driver on startup.
4. Run Windows Update and install your laptop maker’s utilities for hotkeys and BIOS from its support site (for HP that includes the hotkey support software). These control the Fn row on many models.

Use the on-screen keyboard meanwhile: Settings → Accessibility → Keyboard → On-screen keyboard.

The BIOS check: hardware or software?

The BIOS or UEFI setup runs before Windows or Linux loads, so it is a clean test.

1. Restart and press the setup key as the logo appears (often F2, F10, Del or Esc; your maker’s manual names it).
2. Use the arrow keys, Enter and Esc to move around. Many setup screens have a field where you can type a few letters, such as a search box or an asset tag; do not save changes.
3. Keys work in the BIOS: the hardware is fine. The cause is Windows: settings, layout or drivers above.
4. Same keys dead in the BIOS: it is hardware (dirt, liquid, a loose ribbon cable, a worn key). Some makers ship a built-in hardware test too; HP’s PC Hardware Diagnostics UEFI has a keyboard test under Component Tests.

On a MacBook, Apple adds one more check: if no key works, the Mac may be showing a low-battery alert you cannot see. Connect power or an external keyboard.

An external USB keyboard is the quickest cross-check of all: if it works, the computer and system are fine.

Cleaning and spills

• Crumbs and dust: shut the laptop down, hold it at an angle and blow short bursts of compressed air under the dead key from several sides. Then retest it in the keyboard test.
• Sticky key after a spill: shut down and unplug at once, turn the laptop upside down in a tent shape and let it dry for at least a day. Do not use a hair dryer. Sugary drinks usually need professional cleaning.
• Do not prise off keycaps on thin laptop keyboards unless the maker documents it: the clips break easily.
• Under warranty: contact the maker before opening anything.

For other devices that act up, see controller not detected and stick drift. If the keyboard is fine but you want to know what numbers like polling rate mean, read how to read your test results. And if the trouble started on a call, check mic and camera in Zoom, Teams and Discord.