How to test a used controller before you buy
Second-hand pads are good value right up until you discover the drift at home. Two minutes of testing in front of the seller avoids that.
The four checks that matter
Resting drift first, because it is invisible unless you deliberately look for it. Put the controller flat, hands off, and take a timed sample of both sticks.
Then press every button once, pull both triggers to their stops, and rotate each stick slowly around its outer edge. Those four checks catch most worn controllers.
Signs to walk away from
A steady resting offset above roughly 0.04, a button that needs a hard press, a trigger that will not return to zero, or a stick that cannot reach its edge in one direction.
Cosmetic wear matters far less than any of these. A scuffed pad with clean readings is a better buy than a pristine one with a drifting left stick.
Keep the evidence
Download the report card before paying. It is dated, names the controller and lists every measurement, which is useful in a dispute or return.
If you are selling, the same report is a straightforward way to show a buyer the pad is sound.
Ready to check your own controller?
Start the Used Controller Check