This free dead pixel test checks your monitor for dead, stuck, and hot pixels using 13 fullscreen color patterns plus a built-in magnifier and coordinate locator. If you find a defect, switch to the Pixel Fixer tab to attempt a repair, use the Pixel Identifier to diagnose the defect type, or check the Warranty Guide to see if your manufacturer will replace it. If you want the full context, see the full gaming tools hub.
Most dead pixel testers cycle through 5 or 6 solid colors and nothing else. This tool goes further with 13 test colors, 4 diagnostic patterns, a pixel magnifier for close inspection, coordinate tracking for warranty documentation, and a built-in stuck pixel fixer. Run it within 30 days of buying a new monitor – that is the return window most retailers honor for pixel defects.
Disclosure: We may earn a commission when you buy through links on this page. This does not affect our recommendations – we only suggest products we would choose ourselves. Learn more
Dead Pixel Test Tool
Click any color to test it in fullscreen, or hit Start Full Test to cycle through all 13. Scan your entire screen on each color – dead pixels appear as tiny dots that do not match the background.
Pattern Tests
← → Navigate
Space Next
Esc Exit
M Magnifier
C Coordinates
A Auto-cycle
How to Test for Dead Pixels
Dead pixels hide in plain sight. A single red sub-pixel stuck on a 27-inch 1440p display is roughly 0.23mm wide – smaller than a grain of sand. You need a methodical approach to catch them.
- Set your monitor brightness to 100%. Dead pixels are harder to spot at low brightness, especially stuck pixels that emit a faint glow.
- Close all windows and disable overlays. Taskbars, toolbars, and desktop icons cover pixels. The fullscreen test removes all of that.
- Run each solid color. Dead pixels (always black) are easiest to spot on white. Stuck red sub-pixels are easiest to spot on blue or green backgrounds. Test all 13 colors – skipping colors means missing defects.
- Scan methodically, not randomly. Divide your screen into a 3×3 mental grid. Inspect each zone for 5-10 seconds per color. Start top-left, work across, then down. Rushing through colors is the number one reason people miss defects.
- Use the magnifier on suspicious spots. Press M during fullscreen to activate the 10x zoom magnifier. If you see a dot that does not match the background, hover the magnifier over it to confirm it is a pixel defect and not dust on the screen surface.
If you find a defect, press C to toggle the coordinate display and click the defective pixel to record its exact X,Y position. You will need this information if you contact your manufacturer for a warranty claim.
Dead Pixel vs Stuck Pixel vs Hot Pixel
Not all pixel defects are the same, and the type determines whether you can fix it and whether your manufacturer will replace it.
| Defect | Appearance | Cause | Fixable? | Warranty? |
|---|---|---|---|---|
| Dead pixel | Permanent black dot on every color | Transistor failure – the pixel’s switching mechanism is broken and cannot receive electrical signals | No. Hardware failure, no software fix. | Usually yes if within tolerance (varies by brand) |
| Stuck pixel | Always one color (red, green, or blue dot) regardless of what the screen displays | One sub-pixel transistor stuck in the “on” position, continuously emitting light | Sometimes. Color cycling fixes roughly 50-60% of stuck pixels within 30 minutes. | Treated as “bright dot defect” – thresholds vary |
| Hot pixel | Always white – visible as a bright white dot on dark backgrounds | All three sub-pixel transistors (R, G, B) stuck in the “on” state simultaneously | Rarely. Same techniques as stuck pixels but lower success rate. | Treated same as bright dot defects |
| Dust under panel | Irregular shape, may look gray or fuzzy, sometimes visible only at certain angles | Microscopic particle trapped between LCD layers during manufacturing | No (without disassembly). Not the same as external dust on the screen surface. | Depends on manufacturer – some consider it a cosmetic defect |
Quick way to tell the difference: A dead pixel is always black on every test color. A stuck pixel is always one specific color. A hot pixel is always white. If the “defect” disappears when you wipe the screen with a microfiber cloth, it was external dust, not a pixel issue.
Screenshots do not capture dead pixels. If you take a screenshot of a solid red screen and the “dead pixel” appears in the screenshot, it is a software rendering issue, not a hardware defect. Dead pixels are physical transistor failures that exist in the panel itself – the GPU sends the correct color data, but the pixel cannot display it.
How the Stuck Pixel Fixer Works
Stuck pixel fixers rapidly cycle colors (red, green, blue, white, black) at high frequency to force the stuck transistor to switch states. The theory: the liquid crystal material in the pixel gets “jammed” in one orientation, and rapid switching can jostle it back into working order.
Realistic Success Rates
Many pixel fixer sites claim “fixes most stuck pixels.” Here is what actually happens based on aggregated user reports from hardware forums and repair communities:
- Stuck pixels under 1 week old: 60-80% fix rate with 20-30 minutes of color cycling
- Stuck pixels 1-4 weeks old: 30-50% fix rate, may require multiple sessions
- Stuck pixels over 1 month old: Under 20% fix rate – the transistor is likely permanently stuck
- Dead pixels: Near 0% fix rate. Dead pixels are transistor failures, not stuck crystals. No software tool can fix broken hardware.
- Hot pixels: 10-20% fix rate, similar to stuck but harder since all three sub-pixels must be freed
If 30 minutes of cycling does not fix a stuck pixel, try leaving it running for 2-4 hours. If it still does not clear, the pixel is likely permanent. Running the fixer for longer than 8 hours provides no additional benefit and wastes electricity.
The Gentle Pressure Method
Some repair guides suggest placing a damp microfiber cloth over the stuck pixel and pressing gently with a fingertip or the rounded end of a pen cap while the pixel fixer cycles colors. This physical pressure can sometimes help the liquid crystal realign. Use extreme caution: pressing too hard or using a sharp object can crack the panel glass or damage surrounding pixels. This is a last resort, not a first step.
Monitor Return Policies by Brand
Manufacturers disagree on how many dead pixels justify a replacement. Four brands (Dell, BenQ, MSI, CORSAIR) offer zero-tolerance policies where a single dead pixel qualifies for replacement. Others require 3-6 or more. Use the Warranty Guide calculator above to check your specific situation, or review the summary table below.
| Brand | Dead Pixel Threshold | Bright Pixel Threshold | Warranty | Notes |
|---|---|---|---|---|
| Dell | 1+ (Premium Panel Guarantee) | 1+ bright pixel | 3 years | Zero-tolerance on UltraSharp and some Alienware. Standard Dell monitors use ISO 13406-2 Class II (requires multiple defects). |
| ASUS | 5+ dark sub-pixels | 3+ bright sub-pixels | 3 years | ASUS counts sub-pixels, not whole pixels. ROG and ProArt lines may have different thresholds. |
| Samsung | 3+ or 1 center | 5+ sub-pixels | 1-3 years | Center-zone defects may qualify with fewer pixels. Samsung counts sub-pixels. Within return window, use the retailer instead. |
| LG | 5+ total defects | 5+ total defects | 1-3 years | Uses ISO 9241 standards with defect zones. UltraGear gaming monitors may have more lenient retailer partnerships. |
| Acer | 6+ or 1 center cluster | 6+ bright sub-pixels | 3 years | Follows ISO 13406-2 standards. Predator and Nitro lines sometimes offer better terms through retailers. |
| BenQ | 1+ (Zero Pixel Defect) | 1+ (Zero Pixel Defect) | 3 years | One of the best policies in the industry. Any pixel defect qualifies for replacement under warranty. |
| MSI | 1+ (varies by line) | 1+ (varies by line) | 3 years | Zero dead pixel warranty on most gaming monitors. Verify your specific model is covered. |
| AOC | 3+ dead pixels | 5+ bright sub-pixels | 3 years | Follows ISO 9241-302 Class II for most monitors. AGON gaming line may have better terms. |
| Gigabyte | 3+ dead pixels | 5+ bright sub-pixels | 3 years | Standard ISO policy. AORUS gaming monitors may have separate provisions. |
| ViewSonic | 3+ dead pixels | 3+ bright sub-pixels | 1-3 years | One of the more lenient non-zero-tolerance policies with a lower threshold than many competitors. |
| HP | 5+ total defects | 5+ total defects | 1-3 years | HP follows ISO standards. OMEN gaming monitors may be handled differently. |
| Lenovo | 5+ or cluster of 3+ | 5+ bright sub-pixels | 1-3 years | Follows ISO standards. Clusters of 3+ defects in a small area may qualify separately from scattered defects. |
| CORSAIR | 1+ (Zero Dead Pixel) | 1+ (Zero Dead Pixel) | 3 years | CORSAIR offers zero dead pixel warranty on Xeneon monitors. Excellent policy for a newer monitor brand. |
Retailer return windows matter more than manufacturer warranties. Amazon (30 days), Best Buy (15 days, 30 for members), Micro Center (30 days), and Newegg (30 days) accept returns for any number of dead pixels within their return period. If you find dead pixels on a new monitor, return through the retailer first – it is faster and easier than filing a manufacturer warranty claim.
OLED vs LCD Pixel Defects
OLED panels work differently from LCDs, and that changes how pixel defects appear and behave.
On an LCD monitor, the backlight is always on. A “dead” pixel on an LCD still receives backlight – the liquid crystal just fails to block or pass it correctly. On an OLED display, each pixel produces its own light. A dead OLED pixel is completely off – no light emission at all. This means dead pixels on OLED are more visible on bright backgrounds and less visible on dark backgrounds (since surrounding pixels are also dark).
OLED-Specific Issues
- Burn-in (image retention) – OLED pixels degrade with use, and static elements (taskbars, game HUDs, channel logos) can leave permanent ghost images. This is not a dead pixel – it is organic material degradation. Pixel cycling tools cannot fix burn-in.
- Dark spot defects – Occasionally an OLED pixel’s organic layer fails prematurely, creating a permanent dark spot. This is the OLED equivalent of a dead pixel and is not fixable.
- Stuck sub-pixels – OLED panels can have stuck sub-pixels just like LCDs. The color cycling fixer can sometimes fix these since the underlying mechanism (transistor stuck in one state) is similar.
This dead pixel test works on OLED monitors. The solid color screens will reveal dead and stuck pixels the same way they do on LCD panels. For OLED burn-in testing, use our Monitor Test Suite which includes uniformity patterns designed to reveal image retention.
Testing on Phones and Tablets
This dead pixel test works in mobile browsers on phones and tablets. Tap the test to enter fullscreen, and tap the screen to cycle through colors. On phones, dead pixels are harder to spot because the pixel density is much higher – a 6.7-inch 1440p phone display packs 437 pixels per inch compared to 109 PPI on a 27-inch 1440p desktop monitor.
When to Test a Phone or Tablet
- Buying a used phone – Always run a dead pixel test before handing over money. Used phone sellers may not disclose pixel defects.
- After a screen replacement – Third-party replacement screens sometimes have more pixel defects than original panels. Test immediately after a repair.
- New device unboxing – Most phone manufacturers have a 14-day return window. Test within the first day.
AMOLED vs LCD Phones
Most flagship phones from Samsung, Google, and Apple use AMOLED (OLED) displays. Budget phones typically use IPS LCD. AMOLED dead pixels are easier to spot on bright test colors because the surrounding pixels produce their own light – a dead pixel creates a stark black void. On LCD phones, dead pixels are slightly less obvious because the backlight still illuminates behind the defective pixel.
Frequently Asked Questions
How do I check my monitor for dead pixels?
Use the Pixel Test tab above to cycle through 13 fullscreen colors. Dead pixels appear as tiny dots that stay a different color from the background. Set your brightness to 100%, close all windows, and scan each color screen systematically by dividing the display into sections. The magnifier tool (press M) lets you zoom in on suspicious spots at 10x magnification.
Can dead pixels be fixed?
True dead pixels cannot be fixed with software. The transistor driving the pixel has failed permanently, and no amount of color cycling will repair broken hardware. Stuck pixels (always one color instead of always black) have a 50-60% fix rate using rapid color cycling tools like the Pixel Fixer tab above. Run it for 20-30 minutes positioned directly over the stuck pixel.
What is the difference between a dead pixel and a stuck pixel?
A dead pixel is always black on every test color because its transistor has failed completely. A stuck pixel is always one specific color (red, green, or blue) because one sub-pixel transistor is stuck in the “on” position. The practical difference: dead pixels are permanent, while stuck pixels can sometimes be fixed with color cycling software.
How many dead pixels is acceptable?
That depends on your manufacturer’s warranty policy. Dell, BenQ, MSI, and CORSAIR replace monitors with even 1 dead pixel under zero-tolerance policies. ASUS requires 5+ dark sub-pixel defects. Samsung requires 3+ or 1 in the center zone. Check the warranty calculator above for your specific brand and situation. If you bought the monitor within the last 30 days, return it through the retailer regardless of the manufacturer’s policy – retailers like Amazon and Best Buy accept returns for any pixel defects within their return window.
Does JScreenFix actually work?
JScreenFix and similar pixel cycling tools work on stuck pixels roughly 50-60% of the time when the defect is less than a week old. They do not work on dead pixels at all. Our Pixel Fixer tab uses the same color cycling principle with additional options: three animation patterns (color cycle, noise, strobe), adjustable speed, and a timer with progress tracking. If JScreenFix did not work for you, try the noise pattern at max speed for 30 minutes – it exercises the pixel more aggressively than basic color cycling.
How long should I run a stuck pixel fixer?
Start with 20-30 minutes. If the pixel has not changed, try a second session of 1-2 hours. For stubborn stuck pixels under 2 weeks old, leaving the fixer running for 4-8 hours overnight has the highest success rate. Beyond 8 hours, additional runtime provides no measurable benefit. If the pixel is still stuck after three sessions totaling 12+ hours, it is likely permanent.
Do dead pixel tests work on phones?
Yes. This test works in any modern mobile browser that supports fullscreen mode. Tap to enter fullscreen, tap to cycle colors. Phone displays have much higher pixel density than desktop monitors (400+ PPI vs 100-160 PPI), so individual dead pixels are smaller and harder to spot. Test in a dark room and bring the phone close to your face for the best chance of catching defects.
Can I check for dead pixels without downloading software?
Yes, that is exactly what this tool does. It runs entirely in your browser using HTML, CSS, and JavaScript. Nothing is downloaded or installed. Your display data stays on your device – the tool does not upload screenshots or pixel data to any server.
Is 1 dead pixel worth returning a monitor for?
If you are within the retailer’s return window (typically 15-30 days), yes. Retailers like Amazon, Best Buy, and Micro Center accept returns for any number of dead pixels. Outside the return window, it depends on the manufacturer: Dell replaces for 1 dead pixel, but Samsung and LG may require 3-5 or more. A dead pixel in the center of the screen is more disruptive than one near the edge, so factor location into your decision.
Do OLED monitors get dead pixels?
Yes, but they work differently. OLED dead pixels are completely off (no light emission) because OLED pixels generate their own light – there is no backlight behind them. Dead pixels on OLED appear as stark black voids on bright backgrounds. OLED panels can also develop burn-in (permanent image retention from static content), which is a different defect entirely and cannot be fixed with pixel cycling tools. This dead pixel test works on OLED monitors for detecting dead and stuck sub-pixels.
Do dead pixels show up in screenshots?
No. Dead pixels are hardware defects in the physical panel. Screenshots capture what the GPU sends to the display, not what the panel actually shows. If you see a dot in a screenshot that looks like a dead pixel, it is a software rendering issue or a GPU artifact – not a pixel defect. To confirm a real dead pixel, wipe the screen surface with a microfiber cloth (rules out dust) and check if the dot appears in the same spot on every test color.
Sources and References
- ISO 9241-302:2008 (successor to ISO 13406-2) – International standard for pixel defect classification in electronic visual displays, defining Class I through IV tolerance thresholds used by most monitor manufacturers in warranty policies
- Dell Technologies Premium Panel Guarantee – the industry’s strictest dead pixel policy requiring replacement for monitors with even one bright sub-pixel defect during the warranty period
- iFixit TFT-LCD panel repair guide – detailed explanation of thin-film transistor failure modes that cause dead versus stuck sub-pixels, including liquid crystal alignment behavior during rapid color cycling
- Photography Life pixel defect analysis by Nasim Mansurov – side-by-side comparison of dead, stuck, and hot pixel behavior on both camera sensors and display panels with macro photography examples showing individual sub-pixel states
