How to test for dead pixels
- Clean the display according to its manufacturer's instructions. Dust can look like a pixel defect.
- Start on white and inspect slowly from one corner to the other. Hide the controls to inspect underneath them.
- Repeat on black, red, green and blue. Look for a dot that stays in the same physical location and does not follow the surrounding color.
- Use gray as an additional check for visible unevenness. Finish whenever you are ready.
Dead pixel or stuck pixel: what should I look for?
A dark defect is often easiest to notice on white or another bright background. A bright or stuck subpixel may stand out on black. Red, green and blue let you compare a suspect spot across different colors.
A spot that disappears after cleaning may have been dust. Broad patches, reflections, image retention and viewing-angle effects differ from isolated pixel defects. This visual check cannot determine the underlying cause.
Does this test fix dead pixels?
No. It displays static colors for inspection; it does not repair pixels or run a flashing routine. If a spot persists, use your monitor's built-in diagnostic if available and check the manufacturer's support and pixel warranty policy. Replacement rules vary by model and defect type.
Can I test a phone, laptop or second monitor?
Yes. Move this window onto the display you want to test before starting. Some mobile browsers cannot hide their address bar or enter true fullscreen. The tool then covers the available browser area. Rotate the phone to inspect areas covered by browser controls. A notch or camera cutout cannot display a test color.
Can a screenshot show a dead pixel?
A screenshot captures the device's image, not its physical panel. To document a suspected panel defect, photograph the screen with another device and follow the manufacturer's support instructions. A clean screenshot does not certify a healthy display.
Privacy and limitations
No camera, uploads or account are needed. This tool changes page colors, not hardware brightness or monitor settings. The session summary records which colors were opened, not whether you inspected them or whether your screen passed.