Keyboard Keys Not Working: Find the Cause
If keyboard keys stop working, first establish whether the failure affects one key, a combination or the whole device. Use the keyboard test, then repeat the same action in another application. A key missing from one web page is not enough evidence to replace the keyboard.
Follow the failure, one change at a time
| Result | Next action |
|---|---|
| Works in a text editor but not this browser | Refocus the page; compare another browser and extensions |
| Works alone but not with other keys | Test the exact group in the ghosting test |
| Correct key position, wrong character | Check the input layout |
| Only Fn, brightness or a system shortcut is absent | Check its actual operating-system action |
| Same key fails in several apps and computers | Inspect the device and contact its manufacturer |
| Entire keyboard disconnects | Compare power, cable, receiver and direct connection |
Start with a controlled comparison
Press the suspect key slowly and release it completely. Check the event inspector and the held-key state. Avoid opening browser shortcuts during the test: losing focus can interrupt the sequence of down and up events.
Save work, then reconnect an external keyboard. Test a direct USB connection rather than a hub if possible. Check batteries on wireless devices. Use a known working cable that supports data when the keyboard supports a removable cable.
For a laptop, compare an external keyboard. If it works, that narrows the investigation to the built-in input path; it does not identify a particular switch or ribbon cable by itself.
Inspect settings before parts
Review the selected keyboard layout, remapping profiles and accessibility settings that filter short presses. Keep a record of settings before changing them. If you use those accessibility features, perform only a temporary comparison and restore them afterward.
For platform-specific checks use the Windows keyboard test, Mac keyboard test or Chromebook troubleshooting guide.
When to seek repair
Repeated failure of the same physical key across devices is stronger hardware evidence than one failed browser test. Note whether pressure or press position changes the result, but do not force the key. A cluster of failures may involve shared circuitry; the visible rows do not establish the electrical wiring.
Check warranty coverage and model-specific service instructions. After a spill, stop applying power to test it. For dry external debris, follow the cleaning guide. Do not pry laptop keycaps or open a managed work device as a first step.