display test
Dead Pixel Test
Show solid colors full-screen so you can visually inspect for dead or stuck pixels.
No accountLocal where possibleRetest anytime
White
CSS screen—
Viewport—
Pixel ratio—
Refresh estimate—
DeviceOK can display patterns and estimate browser frame timing, but visual panel defects still require your inspection and professional measurements require dedicated hardware.
Private by design
Test input is processed in your browser where possible.
Use the result as evidence, not a guess.
This test checks
- White
- Black
- Red
- Green
- Blue
How to read it
A passing browser test confirms that the browser can observe this input/output path.
A failing test narrows the issue but does not by itself prove physical hardware failure.