Plug in a USB controller or pair one over Bluetooth, press any button, and every input shows up live: button tiles light up as you press them, sticks move a dot in a circle, and axes print raw values to four decimals so you can spot drift. Nothing is uploaded — the browser reads the device directly.
Leave the sticks alone and watch the printed values. A slow wander away from .0000 is the drift that makes a character walk on its own in game.
Run through the grid and the axis readout before paying: a button that never lights up or a stick that rests away from zero is visible in seconds.
Read the raw mapping your target pad reports — button count, axis order, id string — before hardcoding indices in a game loop.
No. Reads go from the device to the browser through the Gamepad API and stop there, with no network request involved. The page works with the network disconnected once it has loaded.
That is the main use of the axis readout. Leave the sticks untouched and compare the printed values: anything that settles away from .0000 is drift, and a value that keeps changing without input is a noisy potentiometer or a failing Hall sensor.
Browsers only expose a gamepad after the first button press or stick movement, and the page has to be listening on a secure origin. Press a button on the pad, then look again: the card appears within a frame, usually under 20 milliseconds.
Each stick reports two axes between minus one and plus one, where zero is centered. The value is the raw position the browser receives, printed to four decimals, so a stick that rests at .0412 instead of .0000 shows drift that deadzones normally hide.
Yes, on any browser that implements the Gamepad API. A DualShock or DualSense usually reports the standard mapping, so the tiles match the labels you know; over Bluetooth on Windows some pads arrive without the standard mapping until a driver maps them.
Seventeen is the standard mapping: four face buttons, two shoulder buttons, two triggers, back and start, two stick clicks and four directions. Pads that do not follow the standard layout report whatever number they actually have, which can be more or fewer.
The button only appears when the controller reports a vibration actuator that supports the dual-rumble effect. Keyboards, cheap clones and pads without haptics do not expose one, and some browsers do not pass force feedback through at all.
Buttons, sticks, triggers and vibration for any USB or Bluetooth controller — no install, no upload, tested in the browser.