Dead Pixel and Screen Test
Use full-screen solid colors, gradients, contrast patterns, and motion checks to look for dead pixels, stuck pixels, color banding, backlight issues, and visible screen defects.
The tool displays controlled visual patterns so you can inspect individual pixels, uniformity, gradients, contrast, sharpness, motion, and viewing-angle behavior. Clean the display, use the monitor's native resolution, open the test full screen, and inspect every area from a normal viewing distance.
What does this test measure?
The tool displays controlled visual patterns so you can inspect individual pixels, uniformity, gradients, contrast, sharpness, motion, and viewing-angle behavior.
Why is this test important?
Use full-screen solid colors, gradients, contrast patterns, and motion checks to look for dead pixels, stuck pixels, color banding, backlight issues, and visible screen defects.
How do you run the test?
Clean the display, use the monitor's native resolution, open the test full screen, and inspect every area from a normal viewing distance.
How should results be interpreted?
A consistently black or unchanging dot may indicate a dead or stuck pixel. Uneven patches, steps in gradients, or heavy trails can point to panel, cable, setting, or compression limitations.
Normal and problematic results
A consistently black or unchanging dot may indicate a dead or stuck pixel. Uneven patches, steps in gradients, or heavy trails can point to panel, cable, setting, or compression limitations.
Technical limitations
The browser can show reference patterns but cannot automatically confirm a physical panel defect or replace a manufacturer diagnostic.
Why can the score decrease?
Unstable measurements, denied permissions, unsupported browser APIs, background load, power saving, or an incomplete test can affect the result. When a score changes, the result screen explains the reason.
What should you do if a problem is found?
Retest with another cable, port, browser, and device before deciding that the monitor itself is faulty.
Example Result Explanation
Frequently Asked Questions
What is the difference between a dead pixel and a stuck pixel?
A dead pixel receives no power and stays black on every background. A stuck pixel is still lit but frozen on one colour, so it shows as a constant red, green or blue dot. Run the solid colour screens: a dot that stays black on white is dead, a coloured dot that ignores the background is stuck.
Can a stuck pixel be repaired?
Sometimes. Stuck pixels occasionally recover on their own, or after a rapid colour-cycling pattern is displayed for a while. A truly dead pixel is a hardware fault and cannot be revived by software.
How many dead pixels does a warranty usually allow?
Most manufacturers publish a pixel policy and will only replace a panel above a certain count, often somewhere between one and five depending on brand, panel size and whether the pixel is bright or dark. Check the policy for your exact model before claiming.
I see a dark speck, but is it dust or a dead pixel?
Dust sits on the surface and moves or disappears when you tilt the screen or wipe it with a dry microfibre cloth. A dead pixel is inside the panel and will not move. Clean the screen first, then run the white screen again.