Device Checks
Dead Pixel Test — Check Your Monitor, TV, or Phone
Find dead and stuck pixels on your monitor, TV, or phone. Fullscreen color cycling reveals defects a glance can miss.
Before you start
- 1 Clean your screen — a smudge can look like a dead pixel.
- 2 Maximize your browser. The Start button below requests fullscreen.
- 3 Turn brightness to max for the clearest reveal.
- 4 On each color, scan edge-to-edge for pixels that stay wrong.
- 5 Use arrow keys (← →) on desktop, or tap on mobile, to cycle colors. Esc exits.
5 fullscreen panels in this order: Red → Green → Blue → White → Black. Each one exposes a different defect class.
- Red — reveals cyan dead pixels
- Green — reveals magenta dead pixels
- Blue — reveals yellow dead pixels
- White — reveals always-off pixels
- Black — reveals stuck-on pixels + backlight bleed
After scanning
✓ No defects
Your display is healthy. No further action needed.
⚠ Stuck pixels
Wrong color but lit. Try the stuck pixel fixer below — it works maybe a third of the time.
✗ Dead pixels
Always dark on white, or always lit on black. Check your warranty policy — policies for major brands are listed below.
Stuck pixel fixer
Drag the cycling window over the stuck pixel. Rapid color flashing can sometimes "un-stick" a pixel by flexing the liquid crystals through every state in quick succession. Try 10 to 60 minutes.
⚠ Photosensitivity warning: rapid color cycling at ~5 Hz. If you have photosensitive epilepsy or other sensitivity to flashing lights, skip this section.
Time remaining: 10:00
Warranty policies by brand
Pixel-defect thresholds vary widely. Numbers below are typical consumer-tier policies as of 2026 — always confirm on your model's warranty card before assuming you qualify.
Apple
Any dead pixel typically qualifies for replacement on iMacs and Studio Displays. Stuck pixels are evaluated case-by-case.
Dell
Tiered. Class I monitors (UltraSharp Premier) allow zero bright pixels. Most other monitors: 5+ bright or 8+ dark required for replacement.
LG
Typically requires 3+ bright pixels or 5+ dark within a defined area. Premium gaming and OLED lines are stricter.
Samsung
Similar tiered structure to LG. Premium displays may guarantee zero bright pixels.
ASUS
Many gaming models (ROG, TUF) carry an explicit "zero bright dot" warranty — even one bright pixel qualifies.
BenQ
Typically 3+ defects required. Designer-grade displays (PD, SW series) may be stricter.
Disclaimer: Policies change without notice. Contact the brand or check your warranty card before initiating an RMA.
Dead vs stuck — what you're actually looking at
Dead pixel
The transistor controlling the pixel has failed. The pixel is permanently dark and shows black even when the surrounding area is bright white. No software fix works — the hardware is broken.
Stuck pixel
One of the pixel's three sub-pixels (red, green, or blue) is locked on. The pixel always shows that color, even when the surrounding area is a different shade. Rapid color cycling can sometimes un-stick it.
Frequently asked questions
What's the difference between a dead pixel and a stuck pixel?
A dead pixel is always dark — it shows black even on a white screen because the transistor that powers it has failed. A stuck pixel is always bright in one color (usually red, green, or blue) because one sub-pixel is locked on. Stuck pixels can sometimes be un-stuck with rapid color cycling. Dead pixels are almost always permanent.
Are dead pixels permanent?
In nearly all cases, yes. The underlying transistor has failed, and no software fix can revive it. A handful of users have reported a dead pixel returning after a warm-up or a gentle massage with a soft cloth, but this is rare and unreliable. Your options are warranty replacement or learning to live with it.
Can stuck pixels be fixed?
Sometimes. Rapid color cycling (as in our fixer above) can un-stick a pixel by flexing the liquid crystals through every state in quick succession. Success isn't guaranteed — try for 10–60 minutes, and if it doesn't work, it's likely permanent. Some users report gentle pressure with a soft cloth on the stuck spot also works, but that risks further damage if done wrong.
How many dead pixels are acceptable under warranty?
It depends on the brand and model. Apple typically replaces any display with a dead pixel. Dell has a tiered policy: Class I monitors tolerate zero bright pixels, while most consumer models allow up to 5 bright or 8 dark before qualifying. ASUS offers 'zero bright dot' warranties on many gaming models. Always check your model's warranty card — policies vary widely.
How do I test for dead pixels on my phone or TV?
The same test works: open this page in your phone's browser or your TV's browser app, go fullscreen, and cycle through the colors. On iOS Safari, the address bar hides automatically — tap to advance. On smart TVs, Samsung and LG browsers both support fullscreen. For TVs without a browser, cast the tab from a laptop.
Is there a minimum number of pixels that won't pass quality control?
ISO 9241-307 defines 'pixel fault classes.' Most consumer monitors fall under Class II: a 24-inch display with ~2 million pixels is allowed up to 2 bright, 2 dark, and 5 total sub-pixel faults before failing certification. This is why you can legally buy a 'new' monitor with a few defects and have no warranty claim. Premium 'Class I' monitors (often enterprise or medical grade) allow zero.
Why does my screen look like it has hundreds of dead pixels?
Probably dust or smudges. Clean the screen with a microfiber cloth (dry, or very lightly dampened with distilled water — never glass cleaner, which can damage coatings) and re-test. If the dots move when you tilt the screen, it's dust. If they stay in place, they may be defects. Also check whether your screen has a matte coating — some users mistake matte texture for defects.
Does running this test harm my monitor?
No. Displaying solid colors for a few seconds each is well within normal operation. The pixel fixer sub-tool cycles colors rapidly for up to 10 minutes, which is also safe — though some people are sensitive to rapid flashing, so take breaks or skip it if you have photosensitive conditions.
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