Count presses with the keyboard test
Open the keyboard test and click the test area. The Presses counter goes up once for every key press the browser receives.
- Note the Presses number, then tap the suspect key once, quickly, and release.
- Check that Presses went up by exactly one. Repeat 20 times.
- Now hold the key down for two seconds and release. The counter should go up by one, not once per repeated character.
- Test a key that behaves normally in the same way, for comparison.
Reading the result
| What you see | What it means |
|---|---|
| A quick tap adds two presses | Key chatter. The switch is making contact twice |
| A quick tap adds one press, but letters still double when you type | The key repeat delay is too short for how long you hold keys |
| Every key doubles, not just one or two | A setting, a wireless problem or software, not a worn switch |
| Doubling comes and goes with a wireless keyboard | Low battery or interference |
Fix the repeat delay on Windows
When you hold a key, the system waits a moment and then repeats it. If that wait is very short, a normal keystroke can be read as a hold.
- Press the Windows key, type Control Panel and open it. Choose Keyboard. If you do not see it, set "View by" to Large icons.
- On the Speed tab, move Repeat delay one step toward Long.
- Type a paragraph and see whether the doubling has stopped.
If one or two keys chatter, Windows can also filter them. Open Settings → Accessibility → Keyboard, turn on Filter keys, and in its options choose to ignore quick or repeated keystrokes with a short interval. Start with the shortest setting, since a long one makes typing feel slow.
Fix the repeat delay on a Mac
Open System Settings → Keyboard and move Delay until repeat toward Long. For a chattering key, System Settings → Accessibility → Keyboard has Slow Keys, which requires a key to be held briefly before it counts. Set the delay as short as it will go.
Clean the affected key
- Unplug the keyboard, or switch a laptop off.
- Turn it upside down and tap the back gently to shake out crumbs.
- Use short bursts of compressed air around the key while holding the keyboard at an angle.
- On a mechanical keyboard with removable keycaps, pull the cap with a keycap puller and blow around the switch. Do not pull keys off a laptop keyboard, because the clips break easily.
Wireless keyboards
A weak link can make the keyboard resend a key. Replace or recharge the batteries first. Move the USB receiver to a front port or onto a short extension so it sits within a metre of the keyboard, away from USB 3.0 drives and hubs, which are a known source of 2.4 GHz interference. If the keyboard offers both a receiver and Bluetooth, try the other one.
Mechanical keyboards and chatter
Chatter is a known wear fault in mechanical switches. Check the maker's software for a debounce setting and raise it slightly. A hot-swappable board lets you pull the faulty switch and fit a new one in a minute. On a soldered board, a chattering switch needs to be replaced by someone comfortable with a soldering iron, or claimed under warranty. Your press counts from the test make a clear record for a support request.
Further reference: Official device or browser documentation ↗
Reviewed October 2026 · How we write our guides · Suggest a correction