Luabify Quick device diagnostics

Free Dead Pixel Test & Screen Test Online

Use full-screen solid colors and a grid pattern to inspect dead pixels, stuck pixels, uneven brightness, dirty spots, and possible image retention. Runs in your browser with no install.

Display check

Color & dead pixel test

Use solid colors and a grid to spot stuck or dead pixels.

Full screen makes small defects easier to spot.

Use full screen and inspect the same area across multiple colors. This is a visual browser-based check, not a hardware calibration.

  • Check multiple brightness levels for uniformity.
  • Scan edges and corners for darker spots.
  • Use the grid mode to find stuck pixels quickly.

Result

Review the screen pattern currently shown in the preview. Use the result as a visual inspection guide for dead pixels, stuck pixels, and brightness uniformity.

ModeDead pixel grid
ColorWhite
PreviewInline
MethodVisual check

Why run a screen test online

A screen test online helps you inspect a monitor, laptop display, phone, or tablet for visible panel issues before you keep a new device, buy a used one, accept a repair, or start troubleshooting. It is especially useful when you notice tiny dots that never change, patches that look darker than the rest of the screen, or faint ghost images that stay visible longer than they should.

What this test is designed to show

This browser-based screen test uses full-screen solid colors and a grid view to make visible defects easier to spot. Solid colors help reveal dead pixels, stuck pixels, uneven brightness, color tinting, and possible OLED image retention. The grid view helps you inspect panel consistency, surface marks, and whether defects stay fixed in the same place as you switch backgrounds.

How to interpret the results

Check the same area on several colors. Dead pixels usually stay black or off on every screen. Stuck pixels often remain red, green, blue, or white. Uneven brightness and dirty-screen effect appear as darker or lighter patches, especially on gray. OLED retention or burn-in may look like faint shapes or shadows that remain visible when the background changes. Clean the screen, reduce glare, and use full screen to avoid false positives from dust or reflections.

  • Dots that never change: possible dead pixels.
  • Dots that stay one color: possible stuck pixels.
  • Patches on gray or white: possible uniformity issues or dirty-screen effect.
  • Faint static shapes: possible image retention or OLED burn-in.

This test is visual only. It does not calibrate colors, repair pixels, measure panel response, or confirm instrument-grade display accuracy.

Related tools

Frequently Asked Questions

What does this screen test online check?
This screen test helps you look for dead pixels, stuck pixels, uneven brightness, dirty-screen effect, color tinting, and possible OLED image retention or burn-in. It is a browser-based visual inspection tool.

How do I find dead pixels with this screen test?
Use full screen and cycle through white, black, red, green, blue, yellow, gray, and purple. Check whether a dot stays black or off on every color in the same position.

What is the difference between a dead pixel and a stuck pixel?
A dead pixel usually stays black or unlit on every background. A stuck pixel keeps showing one color, such as red, green, blue, or white, instead of changing with the screen.

Can this page help me spot uneven brightness or dirty-screen effect?
Yes. Gray and white backgrounds are useful for spotting darker or lighter patches, cloudy corners, or dirty-screen effect. These issues are easier to see in full screen with reduced room glare.

Can this screen test help check OLED burn-in or image retention?
Yes, it can help you look for faint ghost shapes or static shadows that remain visible when the background changes. It is a practical visual check, not a certified burn-in measurement.

Why does the screen look different in another browser or device?
Browsers, operating systems, display profiles, brightness settings, and panel types can all affect how colors appear. Compare results on the same device under the same conditions when possible.

Does this screen test work on phones, tablets, laptops, and monitors?
Yes. It works in modern browsers across phones, tablets, laptops, and external monitors. Full-screen support and color handling can vary by device and browser.

How can I get more reliable results from the test?
Go full screen, clean the display, lower room lighting, and inspect slowly at a normal viewing distance first, then up close. That helps separate real panel issues from fingerprints, dust, and reflections.

Is this screen test safe and private?
Yes. It only renders colors and a grid pattern in your browser. It does not access files, store data, or change your display settings.

Can this screen test calibrate my monitor or fix pixels?
No. It does not calibrate colors, repair dead pixels, or adjust hardware settings. It is designed to help you visually confirm whether a visible problem exists.

When should I use this screen test online?
Use it after buying a monitor or laptop, after a screen replacement, before accepting a used device, or whenever you notice dots, patches, tinting, or retention on the display.