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UtilityUpdated 2025-04-11

Dead Pixel Test: How to Check Your Screen for Stuck or Broken Pixels

Run a full-screen dead pixel test on any monitor, laptop, or tablet. This guide walks you through the process, explains the difference between stuck and dead pixels, and covers what to do if you find one.

Introduction

You just unboxed a brand new monitor and everything looks great until you notice it: a tiny dot that will not change color no matter what is on screen. That is a dead pixel, and it is more common than you would think. Our LCD Checker fills your entire screen with solid colors (red, green, blue, white, black) so you can spot any pixel anomalies within seconds. It runs entirely in your browser, works on any device with a screen, and does not require a download.

Step-by-Step Guide

1

Open the tool and go fullscreen

Click the fullscreen button to make the test cover your entire display. This eliminates browser UI distractions and lets you see every pixel on the panel.

2

Cycle through each color

Click anywhere on the screen or use arrow keys to switch between solid red, green, blue, white, and black backgrounds. Each color reveals different types of defects.

3

Inspect carefully

Look across the entire screen slowly. Dead pixels appear as tiny black dots on bright colors. Stuck pixels show as colored dots that stay red, green, or blue regardless of the background.

Pro Tips & Best Practices

Pro Tip

Run this test as soon as you receive a new monitor. Most retailers have a limited return window for pixel defects, often just 14 to 30 days.

Pro Tip

Clean your screen before testing. A speck of dust can look exactly like a stuck pixel and cause unnecessary panic.

Pro Tip

Dim the room lights for the black screen test. A dead pixel on a black background is nearly invisible in a bright room but obvious in a dark one.

Common Mistakes to Avoid

Common Mistake to AvoidConfusing stuck pixels with dead ones. A stuck pixel is colored (often green or red) and can sometimes be fixed with pixel-exercising software. A dead pixel is permanently off and usually requires a panel replacement.
Common Mistake to AvoidTesting on a dirty screen. Dust, fingerprints, and screen protector bubbles can all mimic pixel defects. Wipe down the panel first.
Common Mistake to AvoidRunning the test in a windowed browser. You need fullscreen mode to reveal defects hidden under the browser toolbar or system taskbar.

Frequently Asked Questions

Can a dead pixel be fixed?

Dead pixels are typically permanent because the transistor behind the pixel has failed. Stuck pixels, on the other hand, are sometimes fixable by rapidly cycling colors over the affected area or applying gentle pressure with a soft cloth.

How many dead pixels does a manufacturer consider acceptable?

It depends on the brand and panel class. Budget monitors may allow up to 3 to 5 dead pixels under warranty. Premium panels from brands like Dell or Apple often have a zero-tolerance policy.

Does this test work on phone and tablet screens?

Absolutely. Open it in your mobile browser and tap to cycle colors. OLED screens in particular benefit from the black test since individual pixels turn completely off on OLED panels.

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Dead Pixel Test: How to Check Your Screen for Stuck or Broken Pixels?

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