Online Tool Store
· 4 min read
How to Test a Controller for Stick Drift
Heshan Fernando
Co-founder & COO
Your character walks slowly to the left when you’re not touching anything. Or the camera creeps. Or a menu scrolls on its own. The game feels broken, and the game is fine — the controller is reporting movement that isn’t happening.
Stick drift is a number problem before it’s a visible one, and you can measure it long before it becomes unplayable.
What the controller actually reports
An analogue stick reports two axis values, each from -1 to 1. At rest both should read approximately zero.
They never read exactly zero. Manufacturing tolerance, wear and temperature all produce a small resting offset, which is why games apply a deadzone — a threshold below which input is ignored. A typical deadzone is somewhere between 5% and 10%.
Drift is what happens when the resting value exceeds that threshold. A stick reading 0.07 at rest with a 5% deadzone means the game sees constant input. Below the deadzone the same offset is invisible.
That’s why drift appears suddenly. The offset grows gradually over months, and the day it crosses the deadzone is the day the character starts walking by itself.
Buttons are simpler: they either register or they don’t, and testing is a matter of pressing all of them. Triggers on modern controllers are analogue too, so they have a travel range worth checking for full deflection at both ends.
Why people get stuck here
- Drift is invisible until it isn’t. The value creeps up over months with no symptom.
- Blaming the game. The behaviour appears in one game first, usually whichever has the tightest deadzone.
- Browser detection. Most browsers only expose a gamepad after the first button press, for privacy reasons, so the controller appears absent until you press something.
- Testing without numbers. A visual stick indicator hides a small offset; the raw value doesn’t.
What a good controller test shows
Raw axis values, not just a dot
A visual representation makes 0.07 look like zero. The number doesn’t. If you’re checking for early drift, you need the figure.
Both sticks at rest, untouched
Put the controller down on a flat surface and read the values without touching it. Any axis significantly above zero is drifting.
Every button and both triggers
Including the ones you rarely use — stick clicks, back paddles, the guide button. A dead button you never press is still a dead button when you need it.
| Resting value | Meaning |
|---|---|
| Under 0.02 | Normal |
| 0.02 – 0.05 | Slight offset, usually invisible |
| Over 0.05 | Drift — likely to exceed a game’s deadzone |
| Over 0.15 | Severe, affects everything |
Common mistakes to avoid
- Testing while holding the controller, which introduces tiny movements.
- Cleaning around the stick with liquid that seeps into the electronics.
- Pressing hard on the stick to “fix” it, which accelerates the wear.
- Concluding the controller is fine because one game feels normal — deadzones differ, and the tightest one shows it first.
- Buying a replacement before checking whether a firmware update or a recalibration option exists for that model.
How to do it with Gamepad Tester
The Gamepad Tester shows live raw values in the browser, with no install.
- Connect the controller and press any button so the browser detects it.
- Put it down untouched and read both sticks’ resting values.
- Work through every button and both triggers, checking each registers and each trigger reaches full travel.
- Compare the resting values against the deadzone your games use.
The Gamepad API is what makes this work in a browser, if you’re curious how. Other device checks are in the tools directory.
Frequently asked questions
What is stick drift?
An analogue stick reporting movement when untouched, usually from wear in the potentiometer or debris in the mechanism. It shows as a resting value above zero and as characters moving on their own.
Why does the browser not see my controller?
Most browsers only expose a gamepad after the first button press, for privacy reasons. Press a button and it should appear.
Can drift be fixed?
Sometimes, by cleaning around the stick base with contact cleaner. Often the potentiometer is worn and needs replacing, and a wider deadzone is a workaround rather than a fix.
Final thought
Test a new controller in its first week and note the resting values. When something feels wrong in a year, you’ll have a baseline to compare against instead of a guess.