How the test works
No black box: this is exactly what the tool measures and how it turns that into a grade.
1. Reading the sticks
Modern browsers expose connected controllers through the Gamepad API. Each analog stick is reported as two axes, X and Y, each between −1 and +1. At rest, a perfect stick reads 0, 0. The tool polls these values once per screen refresh – typically about 60 times per second.
2. The 5-second rest measurement
After a 3-second countdown the tool records both sticks for 5 seconds. For every sample it calculates the distance from the centre (√(x² + y²)). If a button is pressed or a stick moves noticeably away from where it rested when measuring began, the test stops, because the result would no longer describe the stick at rest.
From the samples we report, per stick:
- Peak offset – the largest distance from centre seen while resting.
- Average offset – the mean distance from centre.
- Direction – where the stick leans on average (for example “up-left”).
3. Grades, score and deadzone
The grade uses the peak offset, because a single twitch past the deadzone is what makes a character move. Offsets are shown as a percentage of full stick travel:
- No driftunder 3%Rests cleanly
- Minor drift3% – 8%Hidden by most games
- Moderate drift8% – 15%Likely noticeable
- Severe drift15%+Needs repair
The score starts at 100 and falls linearly to 0 at a 25% peak offset. The deadzone suggestion is the peak offset plus a 2-point safety margin, rounded up (minimum 3%). Above 25% we don’t suggest a value, because a deadzone that large would swallow real stick movement. These thresholds are our own practical guide, not an official standard from any controller maker.
Limits of a browser test
- Your operating system and browser may apply their own small deadzone or smoothing, and some controllers report slightly different values over Bluetooth than over USB. If the result is borderline, test both.
- Controllers in non-standard modes (for example some 8BitDo modes) can report axes in a different order. The status line warns you when the browser doesn’t recognise the standard layout.
- Drift can come and go with temperature and use. A clean result today doesn’t guarantee the stick won’t drift later.
Privacy
All measurements happen on your device. Nothing is sent to a server unless you open a result link, which contains only the numbers shown on it. See the privacy policy.