Dead Pixel Test: How to Check Your Screen for Dead, Stuck & Hot Pixels
A single faulty pixel is all it takes to notice a defect every time you sit down at your monitor. This free dead pixel test runs full-screen white, black, and pure RGB patterns in your browser so you can audit every subpixel on a new LCD, OLED, or laptop display in under two minutes — no download, no installation, nothing uploaded from your machine.
Dead vs. stuck vs. hot pixels: what you are actually looking for
A pixel on an LCD panel is built from three subpixels — one red, one green, one blue — each driven by its own tiny transistor. When that transistor fails completely, the pixel receives no voltage at any time. It stays black on every color you display, including a full white screen. That is a true dead pixel (also called a dark dot defect).
A stuck pixel is different: the transistor works, but one or two subpixels are frozen at maximum output. The result is a tiny dot that glows red, green, or blue no matter what the surrounding image shows. Stuck pixels are usually visible on black and mid-gray backgrounds but can hide on matching solid colors, which is why a full color cycle matters.
Hot pixels appear only at long exposure or high brightness in cameras, but on monitors the term is often used for always-white dots — a subpixel stuck fully open. On OLED panels, where each pixel emits its own light, a permanently dark dot usually indicates a degraded emitter rather than a transistor fault, and a permanently bright dot indicates a shorted one.
How to run the dead pixel test correctly
Clean the screen first with a microfiber cloth — dust and fingerprints are routinely mistaken for pixel defects. Then dim the room. Ambient glare can mask a faint dark dot on a white field.
Enter fullscreen mode (press F) and step through each solid color: white reveals dark dots, black reveals bright and stuck dots, and pure red, green, and blue isolate individual subpixels. Move your view progressively across the panel in a grid pattern rather than scanning randomly; a systematic sweep is what professional QC operators do on the factory line.
Give dark colors at least 10–15 seconds per area. Transistor-level defects are static, but slow liquid-crystal response can briefly mimic a dark dot right after a color switch — if a spot disappears after a moment, it was panel response, not a defect.
How many bad pixels is "too many"?
Every panel manufacturer publishes pixel-defect acceptance criteria, usually graded on the ISO 9241-307 class scale. Most monitor brands ship panels rated Class I (zero defects allowed) down to Class II, which permits a small number of dark, bright, or stuck subpixels — often up to 5 of each type, or a lower limit on clustered defects within a 5×5 pixel block.
Practically, this means one stuck pixel in a corner is usually within spec and will not qualify for a warranty replacement, while a cluster of three or more defects within millimeters of each other, or any defect near the center of the screen, often does. Check your manufacturer's published policy before filing a claim, and photograph the defects against our solid test colors as evidence.
Retail return windows are more forgiving than manufacturer warranties. If you are within the store's return period and the test shows any defect you find unacceptable, an exchange is typically the fastest path to a clean panel.
Can you fix a dead or stuck pixel?
True dead pixels (permanently black) are hardware failures and cannot be fixed with software — the transistor no longer switches. Stuck pixels occasionally recover: the pixel just needs its crystals jolted back into motion.
Two approaches are worth trying. First, run rapid color-cycling content over the affected area for 20–60 minutes — our burn-in exerciser mode does exactly this with high-frequency noise and full-spectrum strobes. Second, very gentle pressure on the affected spot with a soft cloth while the screen is off can release a stuck crystal, but this carries a risk of worsening the damage, so it is a last resort.
If the defect persists after exercise, treat it as permanent and decide between living with it, exchanging the panel, or pursuing warranty service.
When to test: new purchases, used panels, and laptops
Run the full sweep within the first few days of ownership on every new monitor, laptop, tablet, TV, or Steam Deck-class handheld. Defect rates are highest in early life, and return windows are short.
For used panels, a dead pixel test also doubles as a quick health screen before purchase negotiations — combine it with the screen uniformity checks for backlight bleed and with the OLED burn-in scan if the panel is organic. High-refresh gaming displays should additionally get a refresh rate verification, since returned units sometimes arrive misconfigured.
Frequently Asked Questions
What is a dead pixel test?+
It is a visual inspection method that fills the screen with solid colors — white, black, red, green, and blue — so defective pixels stand out against the uniform background. A pixel that stays black on white, or stays lit on black, is defective. This page runs the full pattern set in your browser at no cost.
How many dead pixels are normal on a new monitor?+
Most manufacturers ship Class II panels, which allow a small number of subpixel defects (commonly up to 5 dark and 5 bright). Zero-defect Class I panels exist but cost more. One off-center stuck pixel is usually within spec; clusters or central defects are stronger grounds for replacement.
Can a dead pixel fix itself?+
A truly dead (always-black) pixel cannot — its driving transistor has failed. A stuck pixel sometimes recovers after hours of color-cycling exercise. Try the exerciser mode for 30–60 minutes before concluding the defect is permanent.
Does this dead pixel test work on OLED and laptops?+
Yes. The solid-color patterns work on any display technology — LCD, Mini-LED, OLED, laptops, tablets, phones, and TVs. On OLED, remember that a pure black field turns pixels completely off, so inspect black-screen defects using very dark gray instead for the most honest result.
Why do I see small dots that move when I wipe the screen?+
Those are dust or fingerprints, not pixel defects. Always clean the panel with a dry microfiber cloth and re-test before concluding you have bad pixels — a large share of reported defects turn out to be surface debris.
Is a stuck pixel a reason to return a monitor?+
If it is within the retailer return window, yes — most stores exchange panels with any visible defect regardless of manufacturer Class. Outside that window, warranty policy depends on the defect count, type, and location under the manufacturer's published pixel policy.