DeadPixelTest.pro

Dead Pixel Simulator

See exactly what dead pixels, stuck pixels, and hot pixels look like on different background colors — before you go looking for one on your own screen.

Dead Pixel Examples — Simulated

Each panel below simulates a pixel defect on a different background color. The dots are magnified to be visible — actual pixels are much smaller. Notice how the same defect becomes invisible or very prominent depending on the background.

Dead pixel on white

Dead pixels are most obvious on white. They appear as tiny black dots that never move.

Stuck red pixel on blue

A stuck red sub-pixel shows clearly on blue or green backgrounds. It would be invisible on a red background.

Hot pixel on black

A hot pixel (all sub-pixels stuck on) appears as a tiny white dot. Most visible on black.

Stuck green on red

Stuck green shows on red or blue backgrounds. On a green background, it would be invisible.

Dead pixel on red

Dead pixels (black) are still visible on colored backgrounds — they do not match any color.

No dots visible — dead pixel hidden on black

Dead pixel invisible on black

Dead pixels disappear on black. This is how you tell them from stuck pixels — switch to black and they vanish.

Note: Dots above are enlarged ~5× for visibility. Real pixel defects are single pixels — 0.07–0.25 mm depending on your screen resolution and size.

How Big Is a Dead Pixel in Real Life?

Pixel size depends on your display's resolution and physical size. The same 1440p resolution panel looks very different at 24 inches versus 34 inches. Here is a reference for common screen configurations:

ScreenResolutionPPIPixel size
Phone (6.1")2532 × 1170460 PPI0.055 mm
Laptop (13")2560 × 1600227 PPI0.112 mm
Monitor (27" 1440p)2560 × 1440109 PPI0.233 mm
Monitor (27" 4K)3840 × 2160163 PPI0.156 mm
TV (55" 4K)3840 × 216080 PPI0.317 mm

A dead pixel on a 4K monitor is about the size of a grain of sand. On a phone at 460 PPI, it is barely at the limit of naked-eye resolution. This is why methodical scanning at close range is essential — a casual glance will miss it.

Dead Pixel vs Stuck Pixel vs Hot Pixel — What They Look Like

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Dead pixel

Always black — invisible on black, black dot on everything else

Fixable: No — hardware failure

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Stuck pixel

Fixed color — red, green, blue, or purple mix. Glows on black.

Fixable: Often — try fix tool

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Hot pixel

Always white — all three sub-pixels stuck on full brightness

Fixable: Sometimes

Now check your own screen

Use the real dead pixel test to scan your display for any defects.

Run Dead Pixel TestFix Stuck Pixel

Dead Pixel Appearance FAQ

What does a dead pixel look like?+
A dead pixel looks like a single fixed black dot. It is the same size as one pixel — tiny on high-resolution displays. On a white background it is most visible; on a black background it disappears entirely because it is already black. The dot never changes, regardless of what is on screen.
What does a stuck pixel look like?+
A stuck pixel looks like a tiny colored dot — usually red, green, blue, or white — that never changes. On a black background stuck pixels are most obvious because they glow their color against the dark. On a background matching their color they become invisible. A pixel stuck on red shows as a red dot on white or blue backgrounds.
How big is a dead pixel?+
A pixel is the smallest unit of your display. On a 27-inch 1440p monitor, one pixel is about 0.21 mm wide. On a 4K monitor at the same size, a pixel shrinks to 0.16 mm. On a modern phone screen at 400+ PPI, individual pixels are about 0.06 mm — barely visible to the naked eye. Size at viewing distance is what determines whether it is bothersome.
Can I have a dead pixel without knowing it?+
Yes, easily. A dead pixel in the corner of your screen, or on a 4K display at a normal viewing distance, can go unnoticed for months. Many people only discover them when doing a deliberate full-screen color test. A dead pixel in the center of the screen is almost always noticed quickly.