Hardware testers that run in your browser

A hardware tester answers one question: is this device actually doing what it claims? Every tool on this page reads a device through a standard browser API and draws what it sees — no driver, no install, no account. Open the page, press a key or move a stick, and you are looking at the raw event stream your operating system is already producing.

The testers split into four jobs. Input devices — the keyboard tester reports every keydown and keyup with NKRO, ghosting and chatter detection, and draws nine layout standards from ANSI US to ISO Nordic and JIS, with the Nordic tester opening straight on the Æ/Ø/Å board; the mouse tester measures polling rate, click latency, CPS and scroll steps, and the click-speed test times clicks-per-second over a fixed 1 to 60 second run; the gamepad tester shows buttons, trigger travel, stick deflection, dead-zone drift and vibration, and the stick-drift test measures resting deflection as a percentage of full travel over five seconds so a controller that walks on its own gets a number rather than an impression. Displays — the monitor test suite runs dead-pixel, uniformity, response-time and backlight-bleed patterns and the dead-pixel test isolates that one job as a full-screen colour cycle that separates a dead pixel from a stuck one and from dust, the refresh-rate test measures the panel rate your browser actually gets rather than the one Windows reports, the input-lag visualizer puts a ghost cursor next to the real one so you can see frame-time cost, and the OLED burn-in preventer cycles pixels on a panel that has been showing the same HUD for too long. Capture devices — the webcam tester previews the stream with a live FPS and resolution readout, the microphone tester gives a volume meter, waveform and spectrum plus a record-and-play-back loop, and the audio-latency tester measures true round-trip latency with a microphone loopback. The machine itself — GPU and CPU benchmarks, memory and JS-heap information, a screen-info readout and a reaction-time test round out a pre-game or post-build check.

How to choose: start from the symptom, not the tool. A key that repeats or drops is a keyboard-tester job (watch for chatter — two keydowns with no keyup between them). A cursor that stutters is usually polling rate or USB port, which is the mouse tester. A controller that walks on its own is stick drift, which the gamepad tester shows as a resting deflection that is not zero. A screen that looks wrong is the monitor suite first and the refresh-rate test second, because a panel running at 60 Hz when you paid for 144 Hz is a settings problem, not a defect. If several devices misbehave at once, run the CPU and GPU benchmarks — the common cause is thermal throttling, not the peripherals.

Nothing here leaves your machine. The Keyboard, Pointer, Gamepad and Screen APIs deliver events straight to the page; `getUserMedia` hands the camera and microphone stream to an HTML element and a Web Audio analyser node in the same tab. No frame, no sample and no keystroke is written to a file, sent to a server or stored between sessions — there is no upload step in any of these tools because there is nothing to upload. Camera and microphone testers ask the browser for permission first, and the permission ends when you close the tab.

Browser support is the one real limitation. The Gamepad API needs a button press before the controller appears (the browser hides idle controllers on purpose), vibration is Chromium-only, and Safari reports a smaller set of gamepad axes than Chrome or Firefox. For anything involving precise timing — polling rate, latency, refresh rate — close other tabs first: a background tab stealing frames looks exactly like a slow device.