How to Test a Monitor for Dead Pixels
To test for dead pixels, clean the screen, open a solid color in fullscreen, and inspect the panel one color at a time. Use white, black, red, green, blue, yellow, cyan, magenta, and gray.
Quick answer
A dead pixel test works by showing solid colors across the whole screen. A dead pixel may stay dark. A stuck pixel may stay red, green, blue, white, or another color while the rest of the screen changes.
The test does not repair a display. It helps you spot possible problems so you can decide whether to keep testing, document the issue, or contact the seller or manufacturer.
Step-by-step test
First, clean the screen gently with a microfiber cloth. Dust and lint can look like bad pixels, so remove surface marks before you begin.
Second, open the Dead Pixel Test page and press Go Full Screen. Start with white, then black, then red, green, blue, yellow, cyan, magenta, and gray. Move slowly. Check the center, edges, and corners.
Third, use manual mode when you need more time. Use auto-cycle only after you understand what you are looking for. If colors move too quickly, pause the cycle or increase the interval.
What each color shows
White can reveal dark pixels, dust, and pressure marks. Black can reveal bright stuck pixels and backlight issues. Red, green, and blue help you inspect subpixels because each screen pixel is made from those color channels.
Yellow, cyan, and magenta combine color channels. They can reveal problems that are less obvious on red, green, or blue alone. Gray is useful for checking uniformity and faint marks.
Common mistakes
Do not check only one color. A stuck subpixel may hide on some colors and appear on others.
Do not test with browser chrome, menus, or ads visible. Use fullscreen so the whole panel shows the same color.
Do not confuse a speck of dust with a dead pixel. If the mark moves when you wipe the screen, it is not a pixel problem.
Photo and warranty note
If you find a clear issue on a new display, take photos in more than one test color. Include the full screen and a close-up if possible. Check the seller or manufacturer policy for pixel defects. This is a practical note, not legal advice.
Use-case table
| Need | Use | Why |
|---|---|---|
| Main task | Dead Pixel Test | This related tool helps you check the screen with a simple visible state. |
| Next check | Monitor Test | This related tool helps you check the screen with a simple visible state. |
| Extra context | White Screen | This related tool helps you check the screen with a simple visible state. |
Before you finish
Use these tools as simple visual checks. They are useful because they remove distractions and show one screen state at a time. They do not replace hardware repair, professional calibration, device warranty terms or the cleaning instructions from your device maker.
For the best result, test in normal conditions first. Then change one thing at a time, such as brightness, room light or viewing angle. This makes it easier to understand what you are seeing and avoid blaming the screen for dust, glare or an unusual setting.
On mobile, keep the device steady and use a comfortable brightness level. On desktop, move the browser window to the display you want to test before entering fullscreen. If you use more than one display, test each screen separately.
Write down what you see if you are comparing devices. A short note like top left corner, only on blue, or visible on gray can save time later. If you take a photo, include one wide shot and one close shot so the location is clear.
Repeat the check after changing brightness or room light. Some issues look worse at maximum brightness, while fingerprints and reflections may disappear when the angle changes. A second pass helps separate a real display issue from the test setup.
If you are helping someone else, explain what the tool can and cannot do. It can show colors, light and patterns. It cannot confirm warranty coverage, repair pixels, clean the screen for you or measure professional color accuracy.
Keep the process simple. Start with the screen state that answers your main question, then use one or two related tools if you need more context. Clear steps are better than switching through many settings too quickly.
Related ScreenTools
Related guides
Summary
Start with the simple screen state that answers your question. Use fullscreen, keep brightness comfortable, and compare one result at a time. ScreenTools can help you see colors, light and display patterns, but it does not repair hardware or replace device maker instructions.
FAQ
What is the best color for finding dead pixels?
White is good for dark dead pixels. Black is good for bright stuck pixels. Use several colors for a complete check.
Can this tool fix stuck pixels?
No. It only helps you inspect the screen.
How long should I test?
A careful check usually takes a few minutes. Take more time on large monitors.