Dead pixel ALWAYS DARK
A pixel that remains black on bright backgrounds may be dead. Color cycling cannot restore a failed pixel.
How to test your screen
Prepare the display
Gently clean the screen. Use a comfortable brightness and reduce reflections.
Open a solid color
Start the full-screen test, or select a color above. Move the pointer away and let the hints fade.
Look across the panel
Inspect each area for dots that stay dark, stay bright, or differ from their surroundings.
Check all nine colors
Click, swipe, or use the arrow keys. Confirm suspicious dots on several colors, then press Esc to leave.
What does that dot mean?
Stuck subpixel ONE COLOR
A dot that stays red, green, or blue may have a stuck subpixel. Compare it against all primary colors.
Hot pixel ALWAYS BRIGHT
A bright dot on black may be a hot or stuck pixel. These enlarged diagrams are visual guides, not a diagnosis.
Any screen.
A careful inspection.
PHONE
Swipe through the colors. If full screen is unavailable, the test fills the browser viewport. Browser bars, notches, and rounded corners may remain outside the test. On iPhone, use Safari’s Add to Home Screen option and open the saved app to reduce browser chrome; coverage still depends on your device.
LAPTOP
Use the display’s native resolution and inspect without glare. Clean dust away before treating a small mark as a pixel defect.
MONITOR
Move this window to the monitor you want to check before starting. Test each display separately; the tool cannot inspect another screen remotely.
Can dead pixels
be fixed?
A stuck subpixel may recover, but a flashing tool is not a guaranteed repair. Dead pixels caused by hardware failure cannot be repaired by color cycling. Never press or rub the panel to try to fix it.
If a defect persists, check your seller’s return terms or the manufacturer’s pixel policy. Coverage depends on the display and policy; not every isolated pixel qualifies.
A few useful answers.
Does this test detect dead pixels automatically?
No. It displays uniform colors so you can inspect the panel yourself. A browser cannot read the physical state of your pixels.
Can I test an iPhone or Android phone?
Yes. Tap to cycle or swipe between colors. Some browsers cannot enter true full screen, so the test fills the available viewport. It cannot promise coverage beneath browser bars, notches, or rounded screen edges.
Is a black dot always a dead pixel?
No. Dust, a surface mark, or damage can look similar. Clean the screen safely and check multiple colors. A persistent black dot on bright backgrounds is consistent with a dead pixel.
Can the stuck pixel tool repair my screen?
It may help some stuck subpixels, but results are uncertain and it cannot repair dead pixels. The tool flashes a small area only and requires a flashing-content warning to be acknowledged first.
Why is the refresh estimate different from my settings?
The estimate counts animation frames for about one second. Browser scheduling, power saving, display switching, and workload affect it. It is not a certified measurement of the panel’s refresh rate.