Dead Pixel Test
Find dead pixels
in seconds.
Cycle through 10 fullscreen color screens and look for any spot that doesn't match the background — a tiny black dot, a stuck color, or a pixel that stays lit. Works on any monitor, phone, or TV.
HOW TO USE
Three steps, 60 seconds.
Open the test.
Hit Start Pixel Test. Your screen goes fullscreen with the black screen first — ideal for spotting hot pixels instantly.
Cycle through colors.
Use → arrow key, Space, or swipe left to advance. Each of the 10 screens isolates a different defect type.
Mark what you find.
Note the pixel's position on screen. Stuck pixels sometimes recover after 10–15 minutes on a cycling color test.
PIXEL TYPES
Know what you're looking for.
Dead pixels
Stays completely dark.
A dead pixel never lights up. Run the white and color screens — any pixel that stays black is dead.
Stuck pixels
Locked on one color.
A stuck pixel is permanently red, green, or blue. Cycle through the pure-color screens to spot them.
Hot pixels
Always bright white.
A hot pixel stays lit on every screen. Run the black screen first — any bright dot is a hot pixel.
Everything you need to know about dead pixels.
Every screen — whether it's a monitor, laptop, phone, or TV — is made of millions of tiny pixels. Each one has three sub-pixels in red, green, and blue that blend to produce any color. When a pixel stops responding entirely and goes permanently dark, that's a dead pixel: a fixed black dot that stays dark no matter what's on screen. On a bright white background, even a single dead pixel is hard to miss once you know what to look for.
Dead pixels are commonly confused with stuck pixels, which behave differently. A stuck pixel is frozen on a single color — typically red, green, or blue — because one of its sub-pixels can't switch off. A stuck pixel test can reveal whether the issue is temporary; stuck pixels occasionally recover after running a rapid color-cycling session for 10–30 minutes. The third type is a hot pixel: it stays fully lit white on every screen, and the black test screen catches them immediately.
Why Run a Pixel Check?
The most practical reason to check dead pixels online is immediately after buying a new display. Most manufacturers have a warranty policy covering screens with a certain number of defective pixels, but that window closes quickly. A two-minute fullscreen test right after unboxing can save you a complicated return conversation weeks later.
It's equally important when buying second-hand. A stuck or dead pixel tucked into a corner is easy to miss in a quick power-on demo, but it's immediately obvious on a dedicated test screen. Any monitor, phone, or tablet worth buying is worth spending 60 seconds to verify.
How This Dead Pixel Tester Works
This free dead pixel detector cycles your entire display through ten fullscreen color screens: black, white, red, green, blue, cyan, magenta, yellow, checkerboard, and a grayscale gradient. Each screen is designed to expose a specific type of defect.
Start with black — any pixel glowing on a pure black background is a hot pixel. The white screen reveals dead pixels as fixed dark spots that don't change. The primary color screens (red, green, blue) isolate individual sub-pixel faults, while cyan, magenta, and yellow catch the mixed-channel failures that the primaries can miss. The checkerboard and gradient screens handle edge cases: defects that only show up against contrast or where the panel has uneven brightness.
Works on Every Display — Including OLED
This is a fully browser-based dead pixel test — nothing to install and no account required. It works on IPS, LCD, TN, AMOLED, and OLED panels. For an OLED dead pixel test, the black screen is especially telling: on OLED displays, dead pixels go completely dark because each pixel generates its own light with no backlight leaking through. On IPS and LCD monitors, some dead pixels appear very dark grey rather than pure black, which is still easy to spot against a lit screen.
For a dead pixel test on iPhone, open this page in Safari and tap the fullscreen button — no app download needed. Dead pixel test on Android works the same way in Chrome. Swipe left to advance through screens, swipe right to go back. Touch controls work reliably on both platforms, and the layout adapts cleanly to any screen size or orientation.
What to Do If You Find One
If you've spotted a defect, the next step depends on what type it is. A truly dead pixel — permanently dark — is almost always a permanent hardware fault. Take a photo to document the location and size, then review your manufacturer's warranty policy. Many brands will replace a screen with even a single confirmed dead pixel if you're within the coverage period.
A stuck pixel is worth treating before writing it off. Leave this dead pixel test and fix routine running on the fullscreen cycling screens for 15–30 minutes. The rapid color changes can sometimes release a sub-pixel that's been frozen in one state. It doesn't work every time, but it costs nothing to try, and it has brought plenty of stuck pixels back to normal.
This dead pixel checker runs entirely in your browser. No data is collected, no cookies are set, and nothing is sent anywhere. Whether you're inspecting a brand-new 4K monitor fresh out of the box or an older phone screen you've used for years, the fullscreen test gives you a clear answer in well under two minutes.
FAQ
Frequently asked questions.
How do I test for dead pixels?
The quickest way is to run a fullscreen dead pixel test — exactly what this tool does. Click Start Pixel Test and cycle through the 10 color screens using arrow keys, spacebar, or swipe on mobile. On each screen, look for any spot that doesn't match the solid background. A dead pixel stays dark regardless of the screen color. A stuck pixel stays one fixed color no matter what's behind it. The whole check takes under two minutes.
How do I test for dead pixels on a monitor?
Open this page in your browser, click Start Pixel Test, and let it go fullscreen. Use the right arrow key or spacebar to advance through the 10 screens. Start with the black screen — any glowing dot is a hot pixel. The white screen reveals dead pixels as small dark spots. Then cycle through each color screen to catch stuck sub-pixels. On a large monitor, take a moment on each screen and scan from corner to corner before moving on.
How do I test for dead pixels on a laptop?
Same process as a desktop monitor — open this page in your laptop browser and click Start Pixel Test. A practical tip: dim your room lights slightly and tilt the display to cut down on reflections. Laptop panels are often denser than external monitors, so stuck sub-pixels can be subtler. Take your time on each of the 10 screens, especially the pure color ones where individual sub-pixel faults are easiest to notice.
How do I test for dead pixels on Android?
Open this page in Chrome on your Android device and tap Start Pixel Test. The test is fully touch-enabled — swipe left to advance to the next screen, swipe right to go back. It adapts to any screen size and orientation automatically. Pay extra attention to the corners and edges, where pixel defects are slightly more common. No app install needed — it runs entirely in the browser.
How do I do a dead pixel test?
Hit the Start Pixel Test button at the top of this page. Your screen goes fullscreen and starts on black. Advance through all 10 screens: black, white, red, green, blue, cyan, magenta, yellow, checkerboard, and gradient. On each screen, look for any pixel that stands out from the uniform background. Dead pixels appear dark on color screens. Stuck pixels are a vivid color where they shouldn't be. Hot pixels glow on the black screen.
How do I do a stuck pixel test?
Run the same dead pixel test and focus your attention on the solid color screens. A stuck pixel is frozen on one color — typically red, green, or blue — and stays that color regardless of what screen is behind it. Cycle through the red, green, blue, cyan, magenta, and yellow screens. If you see a dot that holds the same shade across multiple different color screens, it's a stuck pixel. The checkerboard screen can also help reveal stuck sub-pixels that are hard to see on a solid background.
Can dead pixels be fixed?
Truly dead pixels — permanently dark and never lighting up on any screen — are hardware failures that no software can reverse. However, many pixels that look dead are actually stuck pixels that still respond to color. If your pixel shows any color at all, or changes slightly between test screens, it's stuck rather than dead and may recover. Try the Pixel Repair tool before writing it off — stuck pixels sometimes respond to a few sessions of rapid color cycling.
Can stuck pixels be fixed?
Often yes. Stuck pixels can sometimes recover by rapidly cycling through thousands of color changes per second. This creates voltage shifts across the sub-pixel transistor that can knock it out of its frozen state. Use the Pixel Repair tool — position the fixer over the stuck pixel and run it for 10–30 minutes. Some pixels come back in one session; others take a few tries over consecutive days. It's always worth attempting before filing a warranty claim.