How to Use This Tool
- Select a Color: Click on any color option above to change the test screen background
- Inspect Carefully: Look for any pixels that don't match the background color
- Mark Dead Pixels: Click on any suspicious pixels to mark them for the report
- Use Fullscreen: For best results, use the fullscreen mode to test your entire display
- Try Patterns: Use grid or crosshair patterns to help identify problematic pixels
- Generate Report: Click "Generate Report" to see your test results and analysis
Test Results
Complete Guide to Dead Pixel Testing
What Are Dead Pixels?
Dead pixels are defective pixels on a display that remain permanently on or off, regardless of what image is being displayed. They appear as tiny dots that don't change color and can significantly affect your viewing experience.
Dead Pixels
Permanently off pixels that appear as black dots even on white backgrounds. These are typically caused by transistor failures.
Stuck Pixels
Pixels stuck on a particular color (red, green, blue, or white). These may be fixable with pixel fixing software.
Hot Pixels
Pixels that are always on and appear as bright spots. More common in camera sensors but can occur in displays.
Bright Pixels
Sub-pixels stuck on, causing abnormally bright spots that are particularly visible on dark backgrounds.
How to Perform a Thorough Test
- Clean Your Screen: Use a microfiber cloth to remove dust and smudges
- Adjust Brightness: Set your screen to maximum brightness for better detection
- Use Multiple Colors: Test with white, black, red, green, and blue backgrounds
- Take Your Time: Spend at least 30 seconds examining each color
- Use Fullscreen Mode: This eliminates distractions and covers your entire display
- Check Different Angles: View your screen from various angles
- Mark Suspicious Pixels: Click to mark any pixels that look abnormal
Interesting Facts About Dead Pixels
- Modern high-resolution displays can have over 8 million pixels (4K displays have 8,294,400 pixels)
- Most manufacturers allow a certain number of dead pixels before considering a display defective (typically 3-5 for monitors)
- Dead pixels are more noticeable on lighter backgrounds, while stuck bright pixels are more visible on dark backgrounds
- The ISO 13406-2 standard classifies pixel defects into four classes, with Class I having zero defects
- Some stuck pixels can be fixed using pixel fixing software that rapidly cycles colors
- OLED displays are less prone to dead pixels but may suffer from burn-in instead
- Dead pixels usually occur due to manufacturing defects or physical damage to the display
- Professional displays often have lower acceptable defect rates than consumer displays
Additional Tips for Pixel Testing
Prevention & Maintenance
- Avoid applying pressure to your screen - this can damage pixels
- Keep your display away from extreme temperatures and humidity
- Use a screen protector to prevent physical damage
- Avoid displaying static images for extended periods to prevent burn-in
- Clean your screen regularly with appropriate cleaning solutions
Troubleshooting Stuck Pixels
- Try pixel fixing software that rapidly cycles through colors
- Gently massage the affected area with a soft cloth (power off first)
- Run the display at different refresh rates to potentially unstick pixels
- Use JScreenFix or similar tools for 10-30 minutes on the affected area
- If under warranty, contact the manufacturer for replacement
When Buying a New Display
- Check the manufacturer's dead pixel policy before purchasing
- Test the display within the return period using this tool
- Premium displays often have better quality control
- Look for displays with Class I or Class II pixel defect classification
- Consider extended warranties for expensive displays
Use Cases for Dead Pixel Testing
New Device Purchase
Test monitors, laptops, tablets, and smartphones immediately after purchase to ensure quality and take advantage of return policies.
Professional Work
Graphic designers, photographers, and video editors need pixel-perfect displays for accurate color representation.
Gaming Monitors
Gamers require flawless displays for competitive gaming and immersive experiences without distracting defects.
Quality Control
Manufacturers and retailers use pixel testing to ensure products meet quality standards before shipping.
Second-Hand Purchases
Verify the condition of used displays before completing a purchase from marketplaces or individuals.
Warranty Claims
Document dead pixels for warranty claims and manufacturer support requests with detailed reports.
About This Tool
The Dead Pixel Test Tool is a professional-grade, browser-based utility designed to help users identify pixel defects on any display device. Built with modern web technologies, this tool provides comprehensive testing capabilities without requiring any software installation.
Key Features
- Fullscreen Testing: Utilize your entire screen for thorough pixel inspection
- Multiple Color Modes: Test with 8 different solid colors to identify various pixel defects
- Pattern Testing: Grid and crosshair patterns for enhanced pixel visibility
- Interactive Marking: Click to mark and track suspected dead pixels
- Detailed Reports: Generate comprehensive test reports with calculations
- Responsive Design: Works on desktops, laptops, tablets, and smartphones
- Timer & Statistics: Track testing duration and click counts
- Auto-Cycling: Automatically cycle through colors for continuous testing
Technical Specifications
- Built with pure HTML5, CSS3, and JavaScript - no external dependencies
- Compatible with all modern browsers (Chrome, Firefox, Safari, Edge)
- Fully responsive design optimized for all screen sizes
- Lightweight and fast - loads instantly without any installation
- Privacy-focused - all testing happens locally in your browser
Educational Value
This tool not only helps identify pixel defects but also educates users about display technology, pixel structures, and quality standards. Understanding these concepts helps make informed decisions when purchasing displays and troubleshooting issues.
Testing Examples & Scenarios
Example 1: New Monitor Testing
Scenario: You just purchased a 27-inch 4K monitor (3840x2160 resolution = 8,294,400 pixels)
Process:
- Start fullscreen test with white background
- Scan entire screen systematically from top to bottom
- Mark any dark spots (dead pixels) - found 2 pixels
- Switch to black background and repeat - found 1 bright pixel
- Test with red, green, and blue to identify stuck sub-pixels - found 1 green stuck pixel
Result: Total 4 defective pixels out of 8,294,400 = 0.00005% defect rate
Action: Within acceptable range for Class II displays, but you may request replacement if under return period
Example 2: Laptop Screen Verification
Scenario: Testing a 15.6-inch laptop with 1920x1080 resolution (2,073,600 pixels)
Process:
- Clean screen thoroughly to remove false positives
- Use fullscreen mode and cycle through all 8 colors
- Marked 0 dead pixels after 5-minute thorough inspection
- Generated report confirming perfect screen condition
Result: 0 defective pixels = 100% perfect screen!
Action: Screen is in excellent condition
Example 3: Smartphone Display Check
Scenario: Buying a used smartphone with 6.5-inch OLED display (2400x1080 = 2,592,000 pixels)
Process:
- Open tool on smartphone browser
- Test each color for 30 seconds each
- Found 3 stuck pixels showing as green dots on black background
- Marked all pixels and generated report
Result: 3 stuck pixels out of 2,592,000 = 0.00012% defect rate
Action: Negotiate price reduction or try pixel fixing software before final decision
How Results Are Calculated
Defect Rate Formula:
Defect Rate (%) = (Number of Dead Pixels / Total Pixels) × 100
Example Calculation:
Resolution: 1920×1080 = 2,073,600 total pixels
Dead Pixels Found: 3
Defect Rate = (3 / 2,073,600) × 100 = 0.00014%
Test Duration Score:
Thoroughness = (Test Duration in seconds / 300) × 100 (capped at 100%)
A thorough test should last at least 5 minutes (300 seconds)
Display Quality Rating:
Excellent: 0 dead pixels
Good: 1-2 dead pixels
Fair: 3-5 dead pixels
Poor: 6+ dead pixels
0 Comments