How to compare one pixel under five colors

A tiny dot on your screen may be hard to judge. It can look bright on one background, disappear on another, or seem to change color. Checking the same spot against five solid colors helps you tell a pixel defect from dust, glare, or a temporary image effect.

Use the Display Test to show solid colors, then note how the spot behaves on black, white, red, green, and blue. This is an inspection, not a repair. If the pixel appears stuck rather than dead, the Stuck Pixel Fixer can try a flashing pattern, but it cannot guarantee a fix.

Check the same pixel under five colors

Open the Display Test and use its color test to show one solid color at a time. Use the same screen and viewing position throughout.
Find the suspicious spot on the first color. Use a nearby corner, edge, or other fixed detail to keep track of its exact position. Avoid zooming the page or moving the test window between colors.
Check the spot on black, then white, red, green, and blue. Pause on each color and note whether the spot looks dark, bright, colored, or indistinguishable from the background.
Return to any color where the spot was easy to see. Confirm that it is still at the same physical point on the screen, not a mark that moved with the page or your viewing angle.
If it appears to be a stuck pixel, you can try the Stuck Pixel Fixer after recording what you saw. Flashing patterns are optional and are not suitable for everyone. Stop if they cause discomfort.

Look closely, but do not press or rub the panel. A fingertip can leave a mark or damage the display, and pressure does not provide a reliable pixel repair.

What the five colors can reveal

The spot stays black on every color

A spot that remains dark on black, white, red, green, and blue may be a pixel or subpixel that is not lighting. On an LCD, this can indicate a pixel that is off. A browser test cannot confirm the underlying panel fault, and a camera photo may make the spot look different from what you see directly.

The spot stays bright or has one fixed color

A bright dot that keeps its color while the background changes may have a subpixel that stays lit. Each pixel combines red, green, and blue subpixels. A stuck red, green, or blue subpixel may stand out clearly on some test colors and blend into others.

The spot changes or disappears on some colors

This can point to one subpixel behaving differently from the others. For example, a weak green subpixel may be harder to notice on a green screen than on red or blue. Record which colors reveal the defect. That pattern can help you describe it to the screen maker, but it does not identify the exact panel component.

The spot appears only on one background or moves

A mark that shifts when you change colors, move your head, or change the page may be dust, a reflection, image retention, or a software overlay rather than a defective pixel. Check the screen surface gently with it turned off, and compare another application or input if possible.

You cannot see a consistent spot

The screen may be fine, or the symptom may be too subtle to confirm under your current lighting. Repeat the check later in a dim, comfortable room. Do not increase brightness to its maximum for a long inspection.

How to get a more reliable comparison

Keep the display conditions steady. Do not change brightness, color mode, or room lighting halfway through the five colors. If night mode or a color filter is active, it can change how the patterns look.
Check night mode and color filters. In Windows 11, check Settings › System › Display › Night light and Settings › Accessibility › Color filters. On a Mac, check System Settings › Displays › Night Shift and System Settings › Accessibility › Display › Color Filters. Turn a feature off only long enough to compare the screen consistently.
Use the display's normal resolution. A non-native resolution can soften edges and make tiny defects harder to locate. On Windows 11, check Settings › System › Display. On macOS, check System Settings › Displays. Keep the resolution and scaling unchanged while testing.
Check whether the mark follows the screen. If it is an external monitor, show the color test on another connected device or input if available. A defect that stays at the same physical point on the panel is more likely to be in the display than in one app.
Do not press the pixel. Pressure can damage the panel or create more problems. Avoid online advice that tells you to massage the screen.

When it may be a hardware defect

A spot is more likely to be a panel defect if it stays at exactly the same location through all five colors and remains visible in different apps or on different inputs. A defect in the same screen location is different from a mark that moves with a window or appears only in one image.

Check the display's return period and warranty terms before trying repair tricks. Policies differ, and a manufacturer may ask for a photo or a count of affected pixels. If the display is new, document the spot and contact the seller before attempting a flashing pattern. For an older screen, a repair shop can advise you, though replacing the panel may cost more than replacing the display.

What a flashing pattern can and cannot do

The Stuck Pixel Fixer rapidly changes colors in an attempt to free a subpixel that is stuck. It may help in some cases, but it cannot repair a pixel that has failed electrically, and a change in appearance does not prove the defect is permanently gone. Recheck the same point under all five solid colors afterward.

Flashing images can trigger discomfort or symptoms in people who are sensitive to flicker. Skip the fixer if that is a concern, and stop immediately if you feel unwell. Nothing you record is uploaded, because this test does not record anything.