Display test
Dead Pixel Test
Cycle through fullscreen colors to find dead, stuck, bright or dark pixels. Press M to mark a defect and Esc to exit.
Use this test when checking a new or used monitor, laptop, phone or TV. Confirm physical pixel defects visually; marker coordinates use CSS pixels.
Shortcuts: ← → change color · M mark defects · H hide controls · Esc exit
Dead pixel test FAQ
How do I check for dead pixels?
Enter fullscreen mode and inspect black, white, red, green and blue backgrounds. A faulty pixel remains fixed in the same position across colors.
How do I mark a faulty pixel?
Press M to enable marker mode, then select the defect. Coordinates appear below and remain only on your device.
What is the difference between a dead pixel and a stuck pixel?
A dead pixel usually remains dark, while a stuck subpixel may remain red, green, blue or bright. The manufacturer’s pixel policy determines whether the panel qualifies for replacement.
Can this test repair a dead pixel?
No. Solid colors help you locate and document a defect but cannot repair physical pixel damage. Avoid pressing or rubbing the panel.
How to get a reliable result
- Clean the screen gently and disable overlays, night filters and automatic brightness.
- Open the test in fullscreen and inspect black, white, red, green and blue at a comfortable brightness.
- Check suspicious points from your normal viewing distance, then inspect them more closely.
- Repeat the same colors after reconnecting or restarting the display to rule out temporary rendering artifacts.
- Record the location and compare it with the manufacturer’s written pixel warranty policy.
Dust, a dirty screen protector, compression in a camera photo and browser zoom can resemble a pixel defect. Confirm the point with your eyes on multiple solid colors.
Related checks and guidance
If the problem is a bright corner or uneven dark field rather than a fixed point, use the backlight bleed and uniformity test. For buying or return decisions, read what to do after finding a dead pixel and the new-device screen checklist. Before contacting support, review how dead pixel warranty policies and evidence requirements differ.