Stick Circularity Test
    Input · Thumbsticks

    Stick circularity test

    Rotate each thumbstick slowly around its outer edge. We trace the shape, measure how far it strays from a perfect circle, and show where the stick rests when you let go.

    Loading test…

    Controller check

    Step 2 of 3 · Buttons, stick drift, stick circularity and rumble motors.

    1. 1Gamepad test
    2. 2Stick circularity test
    3. 3Controller vibration test
    Next: Controller vibration test

    About the stick circularity test

    Updated

    The stick circularity test reads both thumbsticks through the browser's Gamepad API and traces each one on a canvas against an ideal unit circle. It splits the circle into 5° slices, keeps the outermost point you reach in each, and reports the average percentage gap from the circle once 90% of it has been traced. When a stick sits still near the centre it records the resting position, so a resting offset shows up as a percentage of full travel.

    How to use it

    1. Connect your controller and press any button so the browser detects it.
    2. Push the left stick to its edge and rotate it slowly through a few full circles.
    3. Let go of the stick and read the offset at rest.
    4. Repeat with the right stick, and press Reset to start a fresh measurement.

    Frequently asked questions

    What is a good circularity error?

    Lower is better. A stick that reaches the circle evenly in every direction reads close to 0%. Sticks with square gates or outward deadzone tuning read higher on the diagonals, which is not always a fault.

    How do I check for stick drift?

    Let go of the stick and wait a moment. The offset at rest should be at or very near 0%. A steady reading of several percent means the stick does not return to centre.

    Why does the error show a dash?

    The error is only reported once at least 90% of the circle has been traced. Keep rotating the stick slowly at its outer edge until the coverage reaches 90%.