A dark defect, enlarged
A dead pixel looks like a tiny dark square that stays dark on every background. This enlarged drawing shows the idea; a real one is a single dot.
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Dead Pixel Test & Stuck Pixel Check
A dead pixel check that fills your screen with solid colours so you can spot faulty pixels yourself. Run a dead pixels test or stuck pixel test on a monitor, laptop, phone or tablet using fullscreen colours — no app to install, no sign-up. It takes about a minute and never touches your hardware.
Can it fix a pixel? No. There is no repair function here — no flashing fixer, no pressure instructions. For a possible fault, contact the manufacturer or seller.
Clean the screen gently
Wipe dust and smudges with a soft, dry microfibre cloth first. Most “dead pixels” turn out to be dust.
Use normal brightness
Set brightness to the level you normally use. Extreme brightness or dark-room viewing hides real faults.
Inspect every colour
A fault invisible on black can stand out on white or red. Cycle through all nine fields before deciding.
Fullscreen: the test asks for fullscreen only after you press Start Test. If your browser refuses or the device has no fullscreen mode, the test continues in an honest viewport-sized field instead.
Learn to spot a dead pixel
Optional practice with simulated defects drawn by this website. It teaches what to look for — it never tests your real screen and is never required before the real test.
Simulation — these sample defects are drawn by this website.
A stuck pixel changes with the background
This red sample dot glows clearly on the dark background. Switch to the light background and watch it almost disappear — that is why a real inspection must cover every colour.
Find the sample
A small dark sample is hidden somewhere in the panel below. Click or tap where you think it is — keyboard users can Tab to it or use Reveal example.
Sample defects stay clear of the edges. Nothing here is recorded or reported.
How to inspect your screen
- Start Test and look at each solid colour in turn.
- Watch for any dot that does not match the field — dark on bright fields, glowing on dark ones.
- Move through all nine colours with Next, the arrow keys, Space, or a sideways swipe.
- Press H to hide the controls and check the edges, then Exit to finish.
Controls during the test
- ← → or Space — previous / next colour
- H — hide controls, Esc — exit
- Swipe sideways on touch screens to change colour
About edges and cutouts
Browser address bars, notches and camera cutouts can cover parts of the physical display. This test cannot inspect pixels hidden behind them — tilt, scroll or rotate the device to check those areas separately.
Dead, stuck, or just dust?
Three different things people find during a dead pixel test. Only a visual check can tell them apart — this site does not diagnose your display automatically.
Dead pixel
Always dark, on every colour
A pixel that receives no power never lights up, so it stays black whether the field is white, red or blue. Easiest to confirm on a bright white field.
Stuck pixel
One fixed bright colour, usually on dark fields
A pixel frozen on red, green or blue glows against black but may vanish on white. This site offers no flashing fixer and no pressure or massage instructions — those can damage a panel.
Dust or smudge
Moves or wipes away
Dust has soft, irregular edges and often sits slightly above the glass. If the spot changes when you tilt the screen or disappears after gentle cleaning, it was never a pixel.
Screen map — record what you saw
Optional. After (or during) the test, click the rectangle to mark approximately where a suspicious spot appeared. Positions are approximate — not physical pixel coordinates. Notes stay in this browser session only, unless you tick the box below.
Your spots (0)
- No spots recorded yet.
Results
No colours inspected yet. Run the test — visited colours are ticked automatically, and you can tick or untick them by hand.
Download your summary
Produces a “User-reported visual inspection” note with the date, colours inspected and your own observations. It records what you reported — it does not capture, verify or prove a physical screen defect.
Guide
Learn more
Short guides that explain what you are seeing. The test itself stays on this page.
Dead Pixel vs Stuck Pixel — How to Tell the Difference
Always-dark versus frozen-bright: learn which is which, why dust looks similar, and what to check on every colour.
How to Check for Dead Pixels — Step-by-Step Inspection
From wiping the screen to saving your inspection note: the full step-by-step pass in about a minute.
LCD Dead Pixel Test — Check a Monitor or Laptop Screen
For monitors and laptops: viewing distance, the full colour cycle, corner checks, and second-hand buying tips.
OLED Dead Pixel Test — Check a Phone or Tablet Screen
For phones and tablets: landscape mode, swipe controls, notch caveats, and confirming tiny suspects on dense screens.
Black Screen Test — Find Stuck Pixels on a Pure Black Field
Pure black exposes what bright fields hide: glowing stuck pixels, backlight bleed, and edge faults.
White Screen Test — Find Dead Pixels on a Pure White Field
Pure white confirms dead pixels: any dot that stays dark here deserves a second look on black.
RGB Screen Test — Check Red, Green and Blue Subpixels
Red, green, blue in turn: isolate each subpixel to name the fault white and black alone cannot.
Dead Pixel Warranty Policy — Will One Bad Pixel Qualify?
One dot rarely means automatic replacement: how pixel policies decide, and what to prepare before you claim.
Can Dead Pixels Be Fixed? Myths Versus Safe Next Steps
No safe home fix exists here: why flashing and pressure are refused on this site, and what to do instead.
Frequently asked questions
How do I test for dead pixels?
Press Start Test above for a free dead pixel check. The screen fills with nine solid colours — black, white, red, green, blue, cyan, magenta, yellow and medium grey. This dead pixels test doubles as a stuck pixel test: look for any dot that does not match the background on each colour, and press H to hide the controls while you check the edges.
What does a dead pixel look like?
A tiny black dot that stays black on every colour, including white. Then rule out dust: tilt the screen and wipe gently with a microfibre cloth. Dust blurs or moves; a dead pixel stays sharp and fixed.
What is the difference between a dead pixel and a stuck pixel?
A dead pixel receives no power and is black on all backgrounds. A stuck pixel still receives power but is frozen on one colour, so it glows red, green or blue on dark backgrounds and may vanish on white. Black reveals stuck pixels; white confirms dead ones. See the fix section below for why neither has a reliable at-home repair.
Which colours should I use?
All nine. White exposes dead pixels, black exposes stuck pixels, red, green and blue isolate each subpixel, and the rest catch what they miss. A fault invisible on one colour often stands out on another.
How do I test a monitor or laptop?
Clean the screen, use normal brightness, press Start Test — nothing to install. Sit at your usual distance, cycle all nine colours, hide the controls to check the corners. On a second-hand display, run the full cycle and save the summary before you buy.
Can I test an Android phone, iPhone or tablet?
Yes — it runs in the mobile browser, no app needed, so checking for stuck pixels on iPhone works the same as on Android phones and tablets. Rotate to landscape for the largest field and swipe sideways to change colours. Notches, cutouts and the address bar cover small areas, so check those parts separately.
Why does fullscreen not work on my browser?
Fullscreen needs a user action first, so this site requests it when you press Start Test. Some browsers still refuse — iPhone Safari has no fullscreen mode for web pages. The test then continues viewport-sized and says so; the colours work the same.
Can this website automatically detect a defective pixel?
No. It only shows colour patterns; it cannot see your screen and performs no detection or diagnosis. Every conclusion is yours, made with your own eyes.
Will taking a screenshot capture a physical dead pixel?
No. A screenshot captures the image sent to the display, not the physical panel, so faulty pixels never appear in screenshots or recordings. The PNG summary is likewise a written note of what you reported — not a capture of the defect.
Can dead pixels be repaired?
A truly dead pixel — black on every colour — almost never recovers, so most searches for a dead pixel fix end the same way: confirm the fault and talk to the manufacturer or seller. The same applies to queries like “how to fix dead pixels on phone” or a stuck pixel fix — a stuck pixel sometimes returns to normal on its own, but this site offers no repair function: no flashing fixer, no pressure instructions. If you suspect a fault, record it and contact the manufacturer or seller.
Is one dead pixel covered by warranty?
It depends on the manufacturer’s pixel policy. Many makers tolerate a few defective pixels per panel before a screen qualifies for repair or replacement; others are stricter on new premium displays. Check the published policy — this summary is your inspection record, not a warranty certificate.
Does this test upload or save my data?
No. Everything runs in your browser: spot marks live in page memory for the session only, unless you tick the box to keep notes in your browser’s local storage. Summaries are generated locally on download. No accounts. The site measures basic visits with Google Analytics, but your test notes are never sent there. See Privacy.
Honest limits
- Does this site diagnose my display?
- No. It only shows colour patterns. Any conclusion is yours, made with your own eyes.
- Can it fix a pixel?
- No. There is no repair function here — no flashing fixer, no pressure instructions. For a possible fault, contact the manufacturer or seller.
- What are the viewport and pixel-ratio numbers?
- Browser-reported values (CSS pixels and devicePixelRatio). They describe the browser window, not your panel’s verified native resolution.
- What permissions or data are involved?
- None. No camera, microphone, location or recording access; no accounts. Basic visit statistics are measured (see Privacy). Notes stay in your browser.
Technical details
Browser-reported values, rounded for readability. They describe the browser window, not your panel’s verified native resolution.
- Viewport
- …
- Device pixel ratio
- …
Values update if you resize the window or move it to another display.