Free Online Keyboard Tester — Check Every Key Instantly

No — this online keyboard tester is completely private. All key detection runs locally inside your web browser. No keystrokes, key logs, or test results are ever sent to any server. The moment you close the tab, all data is permanently gone. This makes it safe to use even when testing keyboards that have access to sensitive accounts.

There are three common reasons a key does not light up in the tester. First, the key may be physically dead — the switch has failed or was damaged by a liquid spill. Second, the key may be a system-reserved key (such as the Windows key or certain Fn shortcuts) that your operating system intercepts before the browser can detect it. Third, your browser window may not have focus — click anywhere inside the keyboard tool and try again. If one specific key consistently fails to register, it is most likely a dead key that needs cleaning or switch replacement.

Laptop keyboards use special Fn (function) keys that are handled directly by the operating system — things like screen brightness, volume, and Wi-Fi toggles. These keys never reach the browser, so no web-based keyboard tester can detect them. Additionally, some laptop keyboards have keys that are wired differently from standard desktop layouts. For layout-specific help, try our dedicated Laptop Keyboard Tester.

Yes. If your keyboard is double-typing or a key registers twice from a single press, this is called key chatter or switch bounce. Use this tester and press the affected key slowly — if you see it appear twice in the event log from one press, the switch is bouncing. This is usually caused by dust or debris under the keycap, a worn mechanical switch, or a debounce setting that is too low. Try cleaning the switch with compressed air first. If the problem persists on a mechanical keyboard, the switch likely needs to be replaced.

This homepage tester is designed to check individual key functionality — one key at a time. To run a full keyboard ghosting test or N-Key Rollover check, use our dedicated Gaming Keyboard Tester. It lets you hold multiple keys at once and shows exactly how many simultaneous keypresses your hardware can register — a critical check for competitive gaming keyboards.

First, power off your device immediately and let the keyboard dry completely for at least 24–48 hours. Then run a full key test here to identify exactly which keys shorted out. For keys that remain dead after drying, clean underneath the keycap with a cotton swab and 90% isopropyl alcohol. On a mechanical keyboard, individual switch replacement is often possible without replacing the whole board. For a full walkthrough, see our guide on fixing keyboard keys that stopped working.

Yes — this free keyboard tester works on both Windows and Mac. Use the OS dropdown above the keyboard to switch between layouts so that key labels like Option, Command, Alt, and Win match your physical keyboard exactly. The tester runs entirely in the browser and requires no software installation on either operating system.

If you want to test your mouse rather than your keyboard, visit the original CPS Test — a free tool to measure your clicks per second and check whether your mouse buttons are registering correctly.