Dead Pixel Test – Online Screen Test Tool

How to Test Your Screen for Dead Pixels

Testing your screen for dead pixels, stuck pixels, and color accuracy is essential when purchasing a new monitor or troubleshooting display issues. Our free online screen test provides comprehensive testing tools to check your monitor's quality, identify pixel defects, and verify color accuracy—all directly in your browser.

Why Test Your Screen?

Screen testing helps you:

Identify dead or stuck pixels before warranty expires
Check color accuracy and calibration
Detect backlight bleeding or uniformity issues
Verify monitor quality after purchase
Troubleshoot display problems
Test multiple monitors for comparison

Understanding Dead vs Stuck Pixels

Dead Pixels

Dead pixels are permanently black and don't respond to electrical signals. They appear as black dots on colored backgrounds and cannot be fixed. Dead pixels are caused by manufacturing defects or physical damage to the screen.

Stuck Pixels

Stuck pixels are permanently lit in one color (usually red, green, or blue). They appear as colored dots on black or white backgrounds. Unlike dead pixels, stuck pixels can sometimes be repaired using pixel fixing techniques.

Step-by-Step Screen Testing Guide

Enter Fullscreen Mode: Click "Enter Fullscreen Mode" for the most accurate test. This ensures you're testing the entire screen without browser UI interference.
Test Solid Colors: Use the solid color mode and cycle through black, white, red, green, and blue. Look for pixels that don't match the background color.
Use Auto Cycle: Enable auto cycle to automatically switch between colors every 2 seconds. This makes it easier to spot pixel defects.
Check Pixel Grid: Use the pixel check mode to see individual pixels clearly. This helps identify exact pixel locations.
Test Gradient: Use gradient mode to check for color banding and smooth color transitions.
Document Issues: Note the location and type of any pixel defects you find. Take photos if needed for warranty claims.

How to Fix Stuck Pixels

While dead pixels cannot be fixed, stuck pixels can sometimes be repaired:

Pixel Fixing Software: Use software that rapidly cycles colors to "unstick" pixels. Run for 10-30 minutes.
Gentle Pressure: Turn off your monitor, wrap a soft cloth around your finger, and gently massage the stuck pixel area. Turn the monitor back on to check.
Heat Method: Some users report success by gently warming the stuck pixel area with a warm (not hot) cloth, then cooling it.
Pixel Unsticker Tools: Specialized tools apply rapid color changes directly to stuck pixels.
Warranty Replacement: If stuck pixels persist and are in visible areas, contact the manufacturer for warranty replacement.

Testing Color Accuracy

Our screen test includes color accuracy testing:

Primary Colors: Test red, green, and blue to ensure color channels work correctly
Gradient Testing: Check for smooth color transitions without banding
Contrast: Test black and white levels for proper contrast
Uniformity: Check for consistent color across the entire screen

Common Screen Issues

Backlight Bleeding

Backlight bleeding appears as light leaking from screen edges, especially visible on black backgrounds. This is common in LCD monitors and may be more noticeable in dark rooms.

Color Uniformity

Color uniformity issues appear as color variations across the screen. Test with solid colors to identify areas with different tints or brightness levels.

Viewing Angles

Test your screen from different angles. Colors and brightness should remain consistent when viewed from the sides, above, or below.

Warranty and Dead Pixel Policies

Most manufacturers have dead pixel policies:

Zero Dead Pixel Policy: Some premium monitors guarantee zero dead pixels
Acceptable Dead Pixel Count: Many manufacturers allow 1-3 dead pixels, especially on larger screens
Bright Pixel Policy: Stuck pixels (bright pixels) are often covered under warranty
Clustering: Dead pixels clustered together may qualify for replacement even if under the acceptable count
Center Screen: Dead pixels in the center of the screen are more likely to qualify for replacement

Troubleshooting Guides

Frequently Asked Questions

How do I test for dead pixels?

Enter fullscreen mode and cycle through solid colors (especially black, white, red, green, blue). Dead pixels appear as black dots on colored backgrounds. Stuck pixels appear as colored dots on black/white backgrounds.

What is the difference between dead and stuck pixels?

Dead pixels are permanently black and don't respond to signals. Stuck pixels are permanently lit in one color (red, green, or blue). Dead pixels cannot be fixed, but stuck pixels can sometimes be repaired with pixel fixing software or gentle pressure.

Can I fix stuck pixels?

Sometimes. Try pixel fixing software that rapidly cycles colors, apply gentle pressure with a soft cloth, or use a pixel unsticker tool. However, many stuck pixels cannot be fixed and may require screen replacement.

How many dead pixels are acceptable?

Most manufacturers consider 1-3 dead pixels acceptable, especially on larger screens. However, if dead pixels are clustered together or in the center of the screen, you may be eligible for a replacement under warranty.

Does this test work on all monitors?

Yes! Our screen test works on LCD, LED, OLED, and all monitor types. Enter fullscreen mode for the most accurate test results.

Tips for Accurate Testing

Use Fullscreen: Always test in fullscreen mode for accurate results
Clean Your Screen: Clean your monitor before testing to avoid mistaking dirt for dead pixels
Test in Dark Room: Test in a dark room to better see backlight bleeding and pixel defects
Test All Colors: Don't just test black and white—test all primary colors
Take Photos: Document any issues with photos for warranty claims
Test Multiple Times: Run the test multiple times to confirm pixel defects

Ready to test your screen? Scroll up and click "Run Screen Test" to check for dead pixels, stuck pixels, and color accuracy. The test takes just minutes and helps ensure your monitor is in perfect condition.