Free Keyboard Double Click Test — Key Chatter Detector

Keyboard Chatter Detector

Press each key once. Chattering keys will show as having multiple registrations.

Chatter threshold

Idle

Press Start, then press each key ONCE slowly. Any key that registers twice will show chatter events below.

Key	Total presses	Chatter events	Min gap (ms)
No chatter detected yet. Keep pressing keys.

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Keyboard Chatter Detector guide

How to use the Keyboard Chatter Detector accurately

A keyboard double click test (or key chatter detector) finds keys on your keyboard that register two or more presses when you only pressed once. This is called key chatter and it's caused by worn switch contacts bouncing beyond the keyboard's debounce filter window.

01 What Is a Keyboard Double Click Test? A keyboard double click test (or key chatter detector) finds keys on your keyboard that register two or more presses when you only pressed once.

02 How to Read the Results How many times each key registered during the test. If you pressed it once and total says 2, that key is chattering.

03 What Threshold to Use 30ms (strict): Catches only severe chatter. Most worn switches bounce 8-25ms; this will catch the worst ones.

04 Fix Confirmed Key Chatter Once this tool confirms which keys are chattering, fix them using one of these approaches (full guide: Keyboard Typing Double Letters? Key Chatter Fix Guide):

keyboard double click test key chatter detector keyboard chatter test double typing detector Keyboard Chatter Detector Keyboard

Read our full guide on how to fix key chatter once you've identified the affected keys.

Keyboard Chatter Detector FAQ

Common keyboard chatter detector questions

What is keyboard chatter?

Keyboard chatter is when a single physical key press registers as two or more presses. It is often caused by worn or contaminated switch contacts bouncing faster than the keyboard firmware can filter.

How do I fix chattering keys?

Try cleaning the switch, increasing firmware debounce on supported keyboards, or replacing the switch on a hot-swap board. Software debounce can help temporarily, but repeated chatter usually points to a hardware issue.

Is chatter the same as ghosting?

No. Chatter means extra presses from one keystroke, while ghosting means missing or blocked presses during multi-key combinations. They need different tests and fixes.

Checklist

Keyboard checks to confirm

What Is a Keyboard Double Click Test? A keyboard double click test (or key chatter detector) finds keys on your keyboard that register two or more presses when you only pressed once.
How to Read the Results How many times each key registered during the test. If you pressed it once and total says 2, that key is chattering.
What Threshold to Use 30ms (strict): Catches only severe chatter. Most worn switches bounce 8-25ms; this will catch the worst ones.