Dead pixel test

Fill the whole screen with one solid color at a time and look for what stands out.

What is a dead pixel?

A display is built from millions of tiny dots. When one of them fails to show the color it was told to, it's called a defective pixel. Day to day it hides behind photos and text. It usually only becomes visible once a flat, solid color fills the screen.

Before you start

Wipe the screen with a soft cloth. Dust and a pixel fault are hard to tell apart.
Dim the room so your face and the window aren't reflected back at you.
Turn the brightness up a little. Faint patches show up better.

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The screen fills with one solid color at a time. Dimming the room light makes flaws easier to spot.

White
Gray
Black
Red
Green
Blue

Tap the screen or press →← for the next color; ESC or the exit button ends it

Was every color evenly filled, with no odd dots or patches?

Results stay on this screen and are not saved.

Stuck pixel repair attempt

This is an attempt, not a check. Nothing is recorded — run the test above again to see whether it came back.

A square that cycles colors fast sits over the spot you point it at. Stuck pixels sometimes come loose.

Don't do this first

Spending your return window on a repair attempt is not something you can undo. Record the position and color, check the seller's threshold, and only then try this with the time you have left.

It does nothing for a dead pixel — the kind that stays black on every color. Only stuck pixels respond.
The square flashes rapidly. If you're sensitive to light, don't watch the screen directly.
It takes minutes to tens of minutes, and plenty of stuck pixels never come back.

Not sure what the result means?A dead pixel is not a stuck pixel

Dead pixels and stuck pixels are different

A dead pixel never lights up, so it stays black no matter what color you display. A stuck pixel is the opposite: it's frozen on one color, glowing red, green, or blue even on a black screen. Bright on black means stuck; black on white means dead.

On the gray screen you may see broad patches instead of dots. That isn't a pixel fault at all. It's uneven backlighting, usually called screen uniformity. Light leaking from the corners belongs to the same family.

How to double-check what you found

Look at the same spot across several colors. Showing up on only one points to a stuck pixel.
Tilt the screen slightly. If it disappears with the angle, it was a reflection or a fingerprint.
Write down where it is and on which color. "One green dot, bottom right, on black" is enough.
Take a photo if you can. Focus on the screen surface, not through it.

Before you decide on a return

Manufacturers set their own thresholds for how many defective pixels count as a fault, and one or two often don't qualify for an exchange. Check the seller's and the manufacturer's pixel policy first. ReturnCheck doesn't judge whether your screen passes — it helps you record what you saw while the return window is still open.

Screens can also develop symptoms over time. Checking once on arrival and again a few days later is the safer habit.

Checking a whole machine?

Run every browser check in one flow instead of opening them one at a time.

Start the full check

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