Free controller tool · No download
Circularity Test
This joystick circularity test helps you see whether outer stick travel looks round or clipped. Trace the rim slowly and review consistency — a practical circularity check without lab equipment.
Connect your controller
USB or Bluetooth. Press any button if nothing appears.
How to use this tool
- Connect your controller.
- Push a stick to the edge and rotate slowly through a full circle.
- Repeat for the other stick.
- Review how evenly outer samples land.
What the readings mean
Reading circularity scores
A score closer to 1.000 means sampled outer radii were more consistent. Movement speed and incomplete circles affect results. There is no universal manufacturer pass/fail threshold claimed here.
Pair with related stick tools
Use the joystick tester for live axes, the snapback test for release overshoot, and the stick drift test for idle center error.
Compatibility and limitations
Needs dual-axis sticks exposed by the Gamepad API.
Browser sampling rate and hand speed influence results. Treat comparisons on the same machine as more meaningful than absolute scores.
FAQ
What is a circularity test for joysticks?
It checks how consistently a stick holds outer radius while you rotate around the rim.
Why did my score change between runs?
Speed, incomplete circles, and browser timing all move the estimate.
Does poor circularity mean the stick is broken?
Not by itself. Use it as one diagnostic alongside drift and snapback.
Related
Keep testing
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