Gamepad Bench

Gamepad Bench is a free browser-based controller tester with no account or payment. It shows a buttons and triggers map, stick X/Y readings with a deadzone slider, a 10-second stick drift sample, an estimated polling rate (for comparison only), a vibration test and a circularity test.

It supports Xbox Series and One, PS5 DualSense, PS4, Switch Pro and standard PC gamepads, with Chrome or Edge recommended. The page says input is read locally and not uploaded, and that it is not affiliated with Sony, Microsoft or Nintendo.