DEVICE TESTS TOOL
Screen / Dead Pixel Test
Cycle solid colors full-screen to spot dead or stuck pixels.
Go full screen, then click the color area (or press Space/→) to cycle through solid colors — look closely for any pixel that stays a different color than the rest, or an area that flickers. Press Esc to exit full screen.
Black — click or press Space to cycle
About this tool
Cycle a monitor or phone screen through solid black, white, red, green, blue, and gray to spot dead pixels (permanently dark), stuck pixels (permanently lit one color), or backlight bleed/uniformity issues — go full screen for the clearest test, since a spot outside the test area won't be visible.
Frequently asked questions
- What's the difference between a dead pixel and a stuck pixel?
- A dead pixel stays black no matter what color is displayed (it's not receiving power). A stuck pixel stays fixed on one color (often red, green, or blue) regardless of what the screen should show — both show up as a fixed dot that doesn't match the surrounding solid color during this test.
- Why test with multiple colors instead of just white?
- A stuck-red pixel is invisible against a white or red background but obvious against black, green, or blue — cycling through all the primary colors plus black and white catches stuck pixels of any color.
- Can this test fix a dead or stuck pixel?
- No — this only helps you find one. Some stuck (not dead) pixels can sometimes be resolved with gentle pressure or dedicated pixel-fixing techniques you'd look up separately; a genuinely dead pixel is a hardware issue this (or any software) can't repair.