Dead Pixel Test Online
Check your monitor, laptop, TV, or phone for dead pixels, stuck pixels, backlight bleed, and IPS glow. Full-screen color patterns run instantly in your browser.
Dead Pixel Test & Stuck Pixel Fixer
The professional tool to check and fix your screen for dead or stuck pixels, backlight bleed, and uniformity.
How to use the Stuck Pixel Fixer:
- Locate: Find the stuck pixel (bright dot) on your screen using the "Start Dead Pixel Test" button.
- Drag: Launch the fixer and drag the flashing box directly over the stuck pixel.
- Wait: Leave it running for 10 to 20 minutes. The rapid color changes help unstuck the liquid crystals. (For mobile users, use Full Screen mode.)
Run a reliable test
Prepare the display
Clean the panel, use its native resolution, set normal viewing brightness, and reduce reflections in the room.
Inspect every solid color
Enter fullscreen and pause on black, white, red, green, blue, cyan, magenta, yellow, and gray.
Classify and document
Check whether a point stays black, stays one color, or changes with viewing angle. Photograph fixed defects for support.
Understand the result
Dead Pixels
Dead pixels appear as permanently black dots that don't change color regardless of the displayed image. They are usually permanent hardware defects. Multiple dead pixels may qualify for warranty replacement.
Stuck Pixels
Stuck pixels remain fixed on one color (red, green, or blue) and don't respond to image changes. Unlike dead pixels, stuck pixels can sometimes be fixed using our Stuck Pixel Fixer tool.
Backlight Bleed
Light bleeding from screen edges visible on dark colors indicates backlight bleed. Minor bleed is common on LCD/LED monitors. Severe bleed that affects normal viewing may warrant replacement.
Accuracy & methodology
Our testing methodology uses standard Web APIs such as the Fullscreen API and Canvas where supported. Visual inspection conditions affect results.
What this test measures
This dead pixel test uses your browser's fullscreen API to display solid colors across your entire screen. Click 'Start Dead Pixel Test', then cycle through white, black, red, green, blue, cyan, magenta, yellow, and gray. Dead pixels usually appear as black dots on white or bright colors. Stuck pixels appear as fixed bright dots on black or dark colors. All testing happens locally in your browser with no data collection.
What it cannot measure
This browser-based test accurately reveals most visible pixel defects when viewed in a dark room at maximum brightness. However, there are limitations: Very small sub-pixel defects may be hard to see without magnification. Backlight bleed is easier to spot on dark backgrounds. Color accuracy depends on your monitor's calibration. For warranty claims, manufacturers may require specific testing conditions or their own diagnostic tools.
How to interpret the result
Dead pixels appear as permanently black dots that don't change color regardless of the displayed image. They are usually permanent hardware defects. Multiple dead pixels may qualify for warranty replacement.
What to do next
It depends on the manufacturer's pixel defect policy. Most manufacturers (Dell, LG, Samsung, etc.) define an acceptable threshold—typically 1 to 5 dead pixels before a warranty claim is honored. Premium monitors often have better policies (zero dead pixel guarantees). Always check your manufacturer's specific ISO 13406-2 or similar compliance policy and document defects with our test before contacting support.
Types of Dead Pixels
Not all pixel defects look the same. Knowing the type helps you choose the right fix.
Black Dead Pixel
The most common type. The pixel receives no power and stays permanently black regardless of the image displayed. Black dead pixels are usually visible on bright or white backgrounds. They are typically permanent and cannot be fixed with software.
White Dead Pixel (Hot Pixel)
All three sub-pixels (red, green, blue) remain fully lit, producing a bright white dot. Also called a hot pixel. More noticeable on dark backgrounds. Rare on modern LCD panels but more common on older or heat-stressed displays.
Colored Stuck Pixel
One or two sub-pixels are stuck on while others function normally, producing a fixed red, green, blue, cyan, magenta, or yellow dot. Stuck pixels still receive power, which is why they may respond to our Stuck Pixel Fixer tool.
What Causes Dead Pixels?
Understanding the cause helps determine whether repair or replacement is the right option.
Failed Power Connection
The most common cause. Each pixel requires a stable electrical connection to change color between frames. If the thin-film transistor (TFT) controlling a pixel fails or loses connection, the pixel goes permanently dark.
Manufacturing Defect
Display panels are manufactured with millions of pixels—minor defects can occur during production. Most manufacturers allow a small number of dead pixels before offering warranty replacement. Check your manufacturer's pixel policy before filing a claim.
Physical Damage
Impacts, drops, or pressure applied to the screen panel can sever pixel connections or damage liquid crystals. Even minor bumps during shipping can create dead or stuck pixels that appear days after purchase.
Troubleshooting
Clean Before Testing
Always wipe your screen with a lint-free microfiber cloth before running a pixel test. A speck of dust or fingerprint can be mistaken for a dead pixel, giving you a false positive.
What is a stuck pixel?
A stuck pixel is a screen defect where a pixel remains fixed on one color (usually red, green, or blue) instead of changing with the rest of the display. Unlike dead pixels, stuck pixels still receive power and may be recoverable using pixel-fixing tools that rapidly cycle colors to 'unstick' the liquid crystals. Our pixel fixer tool can help repair stuck pixels.
Backlight Bleed
Light bleeding from screen edges visible on dark colors indicates backlight bleed. Minor bleed is common on LCD/LED monitors. Severe bleed that affects normal viewing may warrant replacement.
Are dead pixels covered under warranty?
It depends on the manufacturer's pixel defect policy. Most manufacturers (Dell, LG, Samsung, etc.) define an acceptable threshold—typically 1 to 5 dead pixels before a warranty claim is honored. Premium monitors often have better policies (zero dead pixel guarantees). Always check your manufacturer's specific ISO 13406-2 or similar compliance policy and document defects with our test before contacting support.
When to Use a Dead Pixel Checker
Common moments when a dead pixel test helps you catch screen defects early.
Before the Return Window Closes
Run the test immediately after unboxing a new monitor, laptop, or TV. Most retailers allow returns within 14-30 days. Finding dead pixels early ensures you can exchange the unit before losing your window.
Buying a Used Display
Always test a second-hand monitor before purchase. A quick dead pixel test reveals defects the seller may not have disclosed—or even noticed. Testing in all colors catches both dead and stuck pixels.
After Physical Impact
If your monitor, laptop, or phone was dropped or bumped, run a full pixel test to check for new damage. Pixel defects from physical impact can appear hours after the incident as liquid crystals settle.
Gaming & Professional Use
Gamers, video editors, and graphic designers require defect-free displays. Even a single dead pixel in a critical area of the screen can be distracting during extended sessions. Regular testing ensures your display stays at peak quality.
Frequently asked questions
What is a dead pixel?
A dead pixel is a defective screen pixel that remains permanently black and fails to display any color. Unlike stuck pixels that show a fixed color, dead pixels occur when the transistor controlling that pixel has failed completely. Dead pixels are usually permanent defects and cannot be fixed with software solutions, though warranty coverage may apply for new monitors.
What is a stuck pixel?
A stuck pixel is a screen defect where a pixel remains fixed on one color (usually red, green, or blue) instead of changing with the rest of the display. Unlike dead pixels, stuck pixels still receive power and may be recoverable using pixel-fixing tools that rapidly cycle colors to 'unstick' the liquid crystals. Our pixel fixer tool can help repair stuck pixels.
How do I run the test?
Click 'Start Dead Pixel Test' to enter fullscreen mode, then use keyboard shortcuts 1-0 or click to cycle through test colors. Examine your entire screen on each color to spot any pixels that don't match. Pay special attention to solid colors like white, black, and pure RGB. Press ESC to exit the test at any time.
Can this fix dead pixels?
Dead pixels are typically permanent hardware defects that cannot be fixed with software. However, our Stuck Pixel Fixer can help recover stuck pixels by rapidly flashing colors to encourage the liquid crystals to realign. Run the fixer for 10-20 minutes over the affected area. If pixels remain dead after testing, contact your monitor manufacturer for warranty support.
Does it work on phones and tablets?
Yes, our dead pixel test works on mobile devices including smartphones and tablets. Simply open the test in your mobile browser and tap to cycle colors. For the best results, maximize brightness and test in a dimly lit room. The pixel fixer also works on mobile—use fullscreen mode for optimal coverage.
Will dead pixels spread over time?
True dead pixels (black, no power) generally don't spread—they are isolated transistor failures. However, physical damage that caused one dead pixel can sometimes affect neighboring pixels if the panel structure is compromised. Stuck pixels caused by trapped liquid crystals may occasionally resolve themselves or respond to the pixel fixer tool. Monitor your screen after finding a defect to track whether it worsens.
Are dead pixels covered under warranty?
It depends on the manufacturer's pixel defect policy. Most manufacturers (Dell, LG, Samsung, etc.) define an acceptable threshold—typically 1 to 5 dead pixels before a warranty claim is honored. Premium monitors often have better policies (zero dead pixel guarantees). Always check your manufacturer's specific ISO 13406-2 or similar compliance policy and document defects with our test before contacting support.
Screen Uniformity Test
Check backlight bleed, IPS glow, dirty screen effect, clouding, and color tinting with full-screen solid colors.
Related hardware tests
Continue with another check for the same device or signal.
Screen Uniformity Test
Check backlight bleed, IPS glow, dirty screen effect, clouding, and color tinting with full-screen solid colors.
Refresh Rate Test
Check monitor Hz, 60Hz, 144Hz, 240Hz, frame pacing, and display refresh rate online.
Response Time Test
Check monitor ghosting, motion blur, inverse ghosting, overdrive artifacts, and pixel response online.
Brightness & Contrast Test
Calibrate monitor brightness and contrast with near-black, near-white, ANSI contrast, PLUGE, and white clipping patterns.
Screen Burn-In Test
Check OLED, AMOLED, and LCD image retention using solid colors, gray screens, and checkerboard patterns.
More about dead pixel testing
Guides on dead pixels, stuck pixels, backlight bleed, and monitor defects.
Refresh Rate Test Shows the Wrong Hz? Common Causes and Fixes
If a refresh rate test reports 60Hz on a 144Hz or 240Hz monitor, check OS settings, cable limits, browser throttling, VRR, duplicated displays, and power mode.
Dead Pixels vs Stuck Pixels: How to Tell the Difference Fast
A black dot on white is usually a dead pixel. A bright colored dot on black is usually a stuck pixel. Here is how to check before you try a fix or ask for a return.
How to Calibrate Your Monitor for Better Color (Free and Hardware Methods)
If your monitor looks too blue, too bright, or just wrong, start with sRGB mode, lower brightness, 6500K, and built-in calibration tools before buying a colorimeter.