About Teste Teclado

Teste Teclado is an independent online tool that helps anyone verify whether their physical keyboard is working correctly. The project was born from the need for a simple, installation-free and privacy-respecting way to diagnose dead keys, repeats, stuck keys and anti-ghosting limits.

What it is

It is a web page that captures physical keyboard events through the browser. Each pressed key lights up a visual indicator and is marked as tested when released. There's also an anti-ghosting mode to find out how many keys your keyboard registers simultaneously and a recent-events history panel.

Why the project exists

Many users report keyboard failures without knowing exactly which key is bad or whether the problem is hardware or software. Diagnosing that usually requires installing programs or accessing operating-system-specific tools. Teste Teclado offers a direct alternative: open a page, press keys and receive immediate feedback in any modern browser.

How it works technically

The page listens to global keydown andkeyup events in the browser and matches eachKeyboardEvent.code against the keymap of the selected layout (ABNT2 or ANSI/US). When there's a match, the corresponding virtual key is highlighted. The history keeps a window of recent events along with metrics such as the average time between keypresses and stuck-key detection. None of this is sent over the network: all processing happens locally in your browser.

Known limitations

• Some keys like Fn rarely reach the browser.
• Print Screen can be captured by the system before the page.
• Browser shortcuts like Ctrl+R and Ctrl+W are intentionally ignored.
• On mobile devices, a physical keyboard must be attached.
• Measured timing reflects the browser's perceived delay, not real hardware latency.

How to report a problem

If you encounter unexpected behaviour, want to suggest an improvement or simply leave feedback, get in touch via thecontact page. Clear reports — including browser, operating system and the expected vs observed behaviour — help us prioritise fixes.