Hardware Test Online

How to test for dead pixels

  1. Click the Start Test button below to enter fullscreen mode.
  2. Your screen will show a solid color. Look closely — any pixel that does not display the solid color is a dead or stuck pixel.
  3. Cycle through colors using the on-screen arrows, keyboard arrow keys, or tap the screen. Dead pixels are easiest to spot on pure white; stuck pixels (colored dots) stand out on black.

Found a pixel issue?

  • Stuck pixel (colored dot): Try applying gentle pressure — turn off the screen, place a soft cloth over the spot, press gently for 5-10 seconds, then turn the screen back on.
  • Stuck pixel fixer videos: Search for "pixel fixer" videos on YouTube that rapidly cycle colors to unstick pixels. Run the video at full screen for 10 minutes.
  • Dead pixel (black dot): A truly dead pixel does not light up at all. In most cases, screen replacement is the only fix.

Dead pixel test — free online dead pixel checker & stuck pixel tester

Check your screen for dead pixels and stuck pixels for free. Display 9 fullscreen colors to easily spot pixel defects on any monitor, phone, or laptop screen.

What is a dead pixel test & dead pixel checker?

A dead pixel test (also called a dead pixel checker or pixel tester) is a diagnostic tool that helps you check for dead pixels, stuck pixels, and defective pixels on your screen by displaying solid colors in fullscreen mode. What is a dead pixel? A dead pixel is a pixel on a digital display that does not light up at all, appearing as a constant black spot regardless of what is being displayed. What is a stuck pixel? A stuck pixel receives power but stays fixed on a single sub-pixel color — red, green, or blue — instead of changing to match surrounding content. By cycling through pure black, white, red, green, blue, cyan, magenta, yellow, and gray, this online dead pixel checker makes it easy to spot dead pixels (black dots on any color) and stuck pixels (colored dots that don't change). This pixel tester works on all screen types — LCD monitors, LED displays, OLED phone screens, laptop displays, and tablets. Testing for dead pixels is recommended when you suspect a screen defect, after purchasing a new monitor, before a warranty claim, or anytime you notice black dots or colored spots on your display.

Dead pixel checker — online dead pixel test features

A free browser-based dead pixel test and stuck pixel checker with 9 fullscreen solid colors, keyboard & touch navigation, and a built-in pixel fix guide.

  1. 9 solid fullscreen colors for thorough dead pixel testing: Cycle through 9 distinct colors to check for dead pixels and defective pixels: black, white, red, green, blue, cyan, magenta, yellow, and gray. Dead pixels appear as black dots on every color — white is best for spotting dead pixels. Stuck pixels (red, green, or blue dots) stand out on black backgrounds. A full dead pixel test requires checking all colors.
  2. Fullscreen mode for distraction-free pixel checking: Enter fullscreen mode to fill your entire display with a solid color — no browser UI, no toolbars. This ensures every pixel is tested, including edges normally covered by the browser chrome or taskbar. Essential for a complete dead pixel checker and stuck pixel test.
  3. Keyboard, touch & tap navigation: Use left/right arrow keys to cycle colors, Esc to exit, or tap the screen on mobile devices. On-screen arrows and color dot indicators let you jump directly to any color. Controls auto-hide after 3 seconds so you can check for dead pixels without visual obstruction.
  4. Jump to any color instantly: Before entering fullscreen, tap any of the 9 color preview buttons to start your dead pixel test on that exact color. No need to cycle through all screens — go straight to white for dead pixel detection or black for stuck pixel checking.
  5. Built-in stuck pixel fixer guide: Found a stuck or defective pixel? This dead pixel checker includes a step-by-step guide: the pressure method (gentle pressure with microfiber cloth for 5-10 seconds), pixel fixer videos (YouTube color-cycling at full screen for 10 minutes), and software tools like JScreenFix.
  6. Works on every screen — monitors, phones, tablets, TVs: This online dead pixel test and stuck pixel checker works on any device with a browser. Test your LCD monitor, LED display, OLED phone screen (iPhone or Android), laptop, tablet, or TV. The Fullscreen API works on Chrome, Safari, Firefox, and Edge.

How to check for dead pixels — step-by-step dead pixel test guide

A simple step-by-step process for testing for dead pixels and stuck pixels using this free online dead pixel checker. Learn how to properly check for dead pixels on any screen.

  1. 1. Clean your screen before testing for dead pixels: Dust, smudges, and debris can easily be mistaken for dead pixels or defective pixels. Wipe your screen thoroughly with a clean microfiber cloth before starting the dead pixel test to avoid false positives during your pixel checking.
  2. 2. Click Start Test to begin the dead pixel checker in fullscreen: Click the Start Test button to enter fullscreen mode. Your screen will fill with a solid color. Allow fullscreen permission if prompted. On mobile, the dead pixel test also works inline. Start with white — the best color to check for dead pixels (they appear as black dots).
  3. 3. Cycle through all colors and inspect every pixel: Examine your entire screen carefully on each color. Any pixel not matching the solid background is a defective pixel. Black dots that never light up on any color = dead pixels. Colored dots (red, green, blue) that stay fixed = stuck pixels. Cycle through all 9 colors using arrow keys, screen taps, or the on-screen controls for a complete stuck pixel test.

Found dead pixels or defective pixels? What you can do

Expert tips and techniques for dealing with dead pixels, stuck pixels, and defective pixels — including DIY fixes, stuck pixel checker results interpretation, and when professional repair is needed.

  1. Dead pixel vs stuck pixel vs defective pixel — know the difference: A dead pixel is completely black on every color — it does not light up at all due to transistor failure. A stuck pixel shows as a persistent red, green, or blue dot because one sub-pixel is stuck "on." Defective pixels is a general term covering both. Stuck pixels can sometimes be fixed; dead pixels usually require screen replacement.
  2. Pressure method to fix stuck pixels: Turn off your screen. Place a soft microfiber cloth over the stuck pixel. Apply gentle, steady pressure with your finger or a stylus eraser for 5-10 seconds. Be very careful — too much pressure can crack the screen or create more defective pixels. Turn the screen back on and run the dead pixel test again to check if the pixel is unstuck. Repeat 2-3 times.
  3. Pixel fixer videos & stuck pixel fixer software: Search for "pixel fixer" or "stuck pixel fix" on YouTube. These videos rapidly cycle red, green, blue, and white across the screen to exercise stuck sub-pixels. Position the flashing area over the stuck pixel, set full screen and maximum brightness, and run for at least 10 minutes. Web-based tools like JScreenFix and Windows apps like UDPixel let you target a specific screen region for stuck pixel fixing.
  4. Check your manufacturer warranty for defective pixels: Most monitor manufacturers have dead pixel policies — some replace the screen for even a single bright stuck pixel, while others require 3-5 defective pixels. Bright stuck pixels in the screen center are typically covered more readily than dark dead pixels near edges. Take clear photos of the defect through this dead pixel checker as warranty evidence.
  5. OLED vs LCD — how defective pixels differ by screen type: OLED screens (most phones, high-end TVs) have pixels that emit light directly — a dead pixel on OLED is completely dark. LCD screens use a backlight, so a "dead" LCD pixel may still let some light through and appear gray rather than black. On OLED, burn-in (permanent image retention) can resemble defective pixels but is a different issue. Run the dead pixel test on all colors to distinguish between pixel defects and burn-in.
  6. When to seek professional screen repair for defective pixels: If you find multiple dead pixels or stuck pixels clustered together in a noticeable area, professional screen replacement may be necessary. For phones and tablets, use an authorized service center. For monitors, always check warranty coverage first — out-of-warranty screen replacement often costs nearly as much as buying a new display.

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