Joystick circularity test
Roll the stick slowly around its gate. The plot records the farthest point in every direction and turns it into one error number.
Left stick
Coverage
Average error
Right stick
Coverage
Average error
How to run this test
- Connect the controller and press any button.
- Push one stick all the way out and roll it slowly around the edge twice.
- Do the same with the other stick, then read the coverage and error.
- Press Reset to clear the plot before testing again.
How to read the result
- Coverage
- The share of the 72 direction slices you reached. Keep rolling until coverage passes 90 percent; the error number is only shown once it does.
- Average error
- How far the outer edge strays from a perfect circle, averaged over every direction. Many controllers land between 5 and 15 percent because their gates are slightly square. A sudden dip in one direction is more telling than the overall number.
- Shape of the trace
- Bulges in the diagonals mean the stick reports more than 1.0 in those directions, which some games clip. Flat spots in one direction usually mean wear on that side of the sensor or debris in the gate.
Questions about this test
- Is a high circularity error bad?
- Not on its own. Many pads are designed with square gates and still play well. Compare both sticks on the same controller: a big difference between them is a stronger sign of a problem.
- Why does my stick not reach the edge in one direction?
- A sensor that is wearing out often loses range on one side first. Clean around the stick base and test again. If the dip stays, the module may need replacement.
- Does circularity affect aiming?
- It affects fast diagonal movement more than fine aim. If you play shooters, also run the linearity test, which looks at small movements near the center.