How to run the circularity test
Click Start circularity test, push one stick against its outer edge and roll it slowly round two or three times, then do the same with the other. Keep steady pressure on the rim: the test only counts readings beyond half of full travel, and it fills in a progress bar per stick as it covers the circle in 5° steps. Let go of both sticks when the bars are full and the result appears.
You get the average error for each stick, the edge reach range, and on this page a table of edge reach in eight directions. The weakest direction is highlighted when it falls under 95%.
How to read it
Gamepadla defines circle error as how closely the stick’s movement follows a perfect circle: a high value means a more square-like path, which causes inconsistent speed when moving diagonally. Its measurements give an idea of what healthy controllers score: an Xbox Series controller 6.8% (left) and 7.9% (right) over cable, and a DualSense 6.0% and 6.3% over cable (9.1% and 7.9% when tested through a GuliKit wireless dongle). Gamepadla notes that budget gamepads often have circle errors above 12%.
This tester passes a stick at up to 10% average error and warns up to 20%. It fails a stick above 20%, or one that can’t reach 75% of full travel in some direction, because a character then can’t reach top speed that way.
The direction table tells two faults apart:
- Overshoot at the diagonals (above 100% at ↗ ↖ ↙ ↘): a square output range under a round gate. Normal on many controllers.
- One direction short (for example 82% ↓ while the others read 98%): wear, dirt or a damaged gate on that side. It often goes with drift, so run the stick drift test too.
Fixing poor circularity
If the average error is high but every direction reaches full travel, you can usually leave it. If one direction falls short, recalibrate where the platform allows (the Xbox Accessories app, Nintendo’s Calibrate Control Sticks, the Steam Deck’s calibration screen), then test again. If it is still short, set an outer deadzone so full output arrives before the weak edge: the deadzone visualiser works that out from this test.