Why we built a practical online controller checker
Controller Checker is a browser-based gamepad diagnostic project for gamers, repair technicians, reviewers, and anyone buying or selling a used controller. It turns the native Gamepad API into readable live values without a download or account.
The project focuses on repeatable questions that a visual tester can answer: whether a button activates and releases, whether an analog stick returns near center, whether a trigger reports progressive travel, and whether the browser can expose timing or rumble capabilities. It does not claim to certify hardware from one number.
Why our free gamepad tester runs locally in your browser
Buttons, axes, trigger values, connection state, and browser-visible vibration commands are handled on your device. The project does not need a server to read a controller or create a test result.
Local processing also keeps the workflow fast: connect by USB or Bluetooth, press a button, and start reading the live state. Normal website hosting requests can still create technical server logs, but the changing gamepad values are not submitted as a remote telemetry stream.
What the online controller diagnostic measures and what it cannot
We visualize the signals the browser exposes. Drift values, polling rate, circularity, and vibration support are useful diagnostic hints, but they are not a replacement for manufacturer software, an operating-system hardware panel, or a repair inspection.
The Gamepad API does not consistently expose controller battery state, firmware, raw USB report rate, DualSense adaptive trigger resistance, Switch HD rumble, or controller gyro data. We describe those boundaries on the relevant pages so a missing browser feature is not mistaken for failed hardware.
How Controller Checker content and test guidance are reviewed
Each focused page is written around a distinct troubleshooting task and the controls its live tool actually exposes. We compare behavior across current browser APIs, keep result language cautious, and separate browser estimates from hardware measurements. Pages are reviewed when tools, compatibility, or site architecture change.
Corrections and reproducible compatibility reports are welcome. Include the controller model, connection type, operating system, browser version, page URL, expected behavior, and observed result. That evidence is more useful than a generic report that a controller does not work. Last reviewed: 2026-08-13.