Dead Pixel Test
Check your screen for dead pixels, stuck pixels, OLED burn-in, and screen tearing, all in one tool. Three test modes, no download, works on any device with a browser.
Go full screen and scan each color for a dot that doesn't change. Use the swatches above or the arrow keys to cycle through white, black, red, green, and blue.
Dead pixel, stuck pixel, or something else?
Check a new monitor before the return window closes
Retailers typically give 14-30 days to return a defective display. Running a full dead pixel test the day it arrives is the single most effective way to catch a defect while you still have a return option.
Inspect a used laptop or monitor before buying
Sellers rarely mention pixel defects unless asked directly. Testing in person, or asking a remote seller to run this tool on a video call, surfaces problems a product photo never shows.
Diagnose a suspicious mark you already noticed
If you spotted a dot, patch, or line during normal use, cycling through solid colors tells you whether it is a pixel defect, burn-in, or something else entirely.
Check for OLED and AMOLED burn-in
A full black screen in a dark room reveals faint ghosted shapes, most often a taskbar, status bar, or navigation buttons burned in from months of static use.
Confirm screen tearing before blaming your GPU
A moving reference line makes tearing obvious immediately, helping you decide whether the problem is your display, your cable, or your graphics settings.
Document a defect for a warranty claim
Manufacturers and retailers often want to see the defect reproduced. This tool gives you a controlled, repeatable way to show a dead or stuck pixel on request.
Dead pixels vs. stuck pixels vs. hot pixels vs. burn-in vs. tearing
| Type | Appearance | Cause | Fix |
|---|---|---|---|
| Dead pixel | Always black, on every background color | The subpixel receives no power at all | Rarely self-resolves; usually a hardware/warranty issue |
| Stuck pixel | Locked to one fixed color (often red, green, or blue) regardless of background | The transistor is stuck delivering power to one subpixel | Sometimes resolves with pressure/massage techniques or pixel-fixing software |
| Hot pixel | Unusually bright dot, most visible against black or dark backgrounds | A subpixel drawing more current than it should | Behaves like a variant of a stuck pixel; same troubleshooting applies |
| OLED burn-in | A faint, static ghosted shape (icons, bars, logos), visible mainly on solid colors | Uneven long-term wear of organic LEDs from displaying the same static content | Cannot be reversed by software; panel replacement is the only real fix for severe cases |
| Screen tearing | A horizontal split or misalignment during fast motion, not present on static images | The display refresh is out of sync with the frame being rendered | Software fix: enable V-Sync, G-Sync, or FreeSync, or cap frame rate |
What a subpixel is, and why this test works
Why white alone misses defects
A subpixel stuck on full red is nearly invisible against white, since white already contains full-intensity red, green, and blue. The same stuck red subpixel becomes obvious the instant you switch to a green or blue background, because now it clashes with the surrounding color instead of blending into it.
Why black alone misses defects
A true dead pixel, which produces no light at all, is invisible against black for the same reason: it matches its surroundings perfectly. That is why a full pixel test always requires cycling through multiple colors, not just checking one.
How to run a complete dead pixel test
- 1
Dim the room
Bright ambient light or glare on the screen makes subtle stuck or hot pixels harder to spot. A dim, evenly lit room gives you the clearest read.
- 2
Select Dead / Stuck Pixel mode
Use the mode selector above the preview. This mode cycles through the five colors most likely to expose a defective subpixel.
- 3
Go full screen
A defect near the very edge of the screen can be hidden by a browser toolbar or taskbar if you skip full screen mode.
- 4
Scan methodically on each color
Use the arrow keys to move through white, black, red, green, and blue. On each color, scan in a consistent pattern, left to right, top to bottom, rather than glancing randomly, so you don't skip a section.
- 5
Check from multiple distances and angles
Some defects, particularly on LCD panels, are more visible off-angle. Lean in close, then step back to your normal viewing distance, and check again.
- 6
Switch to Burn-in mode
On OLED or AMOLED devices, run the full black screen in a dark room and look for any faint outline that persists against the black field.
- 7
Switch to Screen Tearing mode
Watch the moving line during motion. A clean single line means no tearing. A visibly split line points to a sync issue you can usually fix in your graphics settings.
Testing for OLED and AMOLED burn-in
What to look for
A very faint variation in brightness or color that traces the outline of something that used to be displayed constantly: a status bar, a set of navigation buttons, a paused video's letterbox bars, or a frequently used app's static UI elements.
Why it only affects OLED and AMOLED
Standard LCD panels use a shared backlight behind every pixel, so they do not develop burn-in the same way. OLED and AMOLED panels light each pixel individually, and organic LED material wears unevenly with use, which is the direct cause of burn-in on phones, TVs, and OLED monitors.
Testing for screen tearing
What tearing looks like
During fast motion, the image appears to split horizontally, with the top and bottom sections momentarily offset from each other, as if two frames were stacked slightly out of alignment. It disappears the instant motion stops.
How to fix it
Enable V-Sync in your graphics settings or the app causing the issue, or use G-Sync (Nvidia) or FreeSync (AMD) if your monitor supports adaptive sync. Capping your frame rate at or below your monitor's refresh rate also reduces tearing significantly.
How many dead pixels are acceptable?
Some premium panel grades are sold under a zero-dead-pixel guarantee, meaning even a single confirmed dead pixel qualifies for a replacement. Standard consumer-grade panels often permit a small number of defects, commonly measured against ISO 9241-307 class ratings used by some manufacturers, before a device is considered defective under warranty. Before assuming a result from this test qualifies for a return or repair, check the specific dead pixel policy published by the manufacturer or retailer for your exact model, since this varies enough that a general rule of thumb is not reliable.
Testing notes by device type
Desktop monitors
Test at your normal seating distance first, then lean in to roughly 12 inches from the panel. Some manufacturers only count a defect if it is visible at normal viewing distance, so document both.
Laptops
Laptop panels are smaller and viewed closer by default, so defects that would be invisible on a 27-inch desktop monitor are often obvious. Tilt the lid slightly to change the viewing angle and re-scan, since some LCD defects are angle-dependent.
External displays and projectors
Projected images are viewed from much further away, so a single dead pixel is unlikely to be visible during real use. Focus more on uniformity, color banding, and hot spots than individual pixel defects.
Phones and tablets
High pixel density makes individual dead pixels harder to spot with the naked eye. Use the color-cycling swatches and look closely at edges and corners, where defects are statistically more common due to panel manufacturing tolerances.
Mistakes that cause a missed or false result
Testing on only one color
Checking white alone, then declaring a screen defect-free, is the single most common mistake. Many stuck subpixels are only visible against specific background colors. Always cycle through all five test colors before concluding a screen is clean.
Testing with bright ambient light or glare
Reflections and glare on a glossy panel can look deceptively similar to a bright or hot pixel, or can mask a genuine dim, stuck pixel. Dim the room before drawing any conclusion.
Confusing dust or debris for a pixel defect
A speck of dust trapped between a screen protector and the panel, or on the glass itself, can look like a stuck pixel from a distance. Wipe the screen with a clean microfiber cloth and check from a very close angle before assuming it is a hardware defect.
Skipping the edges and corners
Manufacturing defects are statistically more common near panel edges and corners. A quick glance at the center of the screen alone is not a complete test.
What to do once you've confirmed a dead or stuck pixel
If you are still within a retailer's standard return window, a confirmed dead pixel is often grounds for a straightforward exchange regardless of the manufacturer's own warranty threshold, since general return policies are usually more generous than dead pixel-specific warranty terms. If you are past the return window, the manufacturer's warranty policy is the deciding factor. See the full dead pixel test guide for a walkthrough of what to document and how to approach a warranty claim.
Can a stuck pixel actually be fixed?
Rapid color cycling
Displaying a fast-changing sequence of solid colors, sometimes for ten to twenty minutes, can occasionally jolt a stuck transistor back into normal operation. The Dead / Stuck Pixel mode above can be cycled manually with the arrow keys to approximate this, though dedicated pixel-fixing software automates it at a much faster refresh rate than a person can click through.
Gentle pressure massage
With the device powered off, some people apply very light, brief pressure to the exact location of a stuck pixel using a soft cloth, then power the screen back on to check. This carries real risk of making things worse, including creating new dead pixels or pressure damage, so it should only be attempted on a device that's already out of warranty and only as a last resort.
Why success isn’t guaranteed
Both techniques work on some stuck pixels and do nothing for others, because the underlying cause varies. A transistor that is genuinely misfiring in a way that responds to rapid switching may recover; a transistor with a physical manufacturing defect will not, no matter how long you cycle colors against it.
When to stop trying
If a stuck pixel doesn't respond after a reasonable attempt, repeating the process for hours rarely changes the outcome. At that point, treat it the same way you would a dead pixel: document it and check your device's specific warranty or return policy instead of continuing to attempt a manual fix.
How major manufacturers handle dead pixel claims
| Category | General approach |
|---|---|
| Premium / zero-defect panels | Sold under a guarantee that any confirmed dead or stuck pixel qualifies for a replacement, often at a price premium reflecting that stricter quality control. |
| Standard consumer panels | Commonly permit a small number of defects, sometimes categorized by defect type and screen zone, before a unit is classified as faulty under warranty. |
| Retailer return policies | Often more generous than manufacturer warranty terms during the standard return window, since general dissatisfaction-based return rules can apply regardless of the manufacturer's specific pixel threshold. |
| Mobile devices | Phone and tablet manufacturers frequently apply their own separate pixel policy distinct from their monitor or TV lineup, sometimes with a shorter defect-reporting window tied to the device's overall warranty period. |
Because these policies change and vary so much by brand, model year, and region, the only reliable step is searching your manufacturer's current support documentation for terms like “dead pixel policy” or “pixel defect warranty” for your exact model before filing a claim.
Reducing the risk of burn-in and pixel stress over time
Avoid long static displays
Leaving a paused video, a fixed dashboard, or a single app's static UI on screen for many hours at high brightness is the single biggest contributor to burn-in over a device's lifetime. Screensavers and auto-dim or auto-sleep settings exist specifically to interrupt this.
Use lower brightness where practical
OLED burn-in progresses faster at higher brightness levels, since the organic material wears proportionally to how hard it's driven. Keeping brightness moderate for everyday use, reserving maximum brightness for when you actually need it, meaningfully extends a panel's uniform lifespan.
Let built-in pixel-shifting features run
Most OLED TVs and phones include a subtle pixel-shifting or logo-dimming feature that nudges static UI elements by a few pixels periodically. Disabling this to eliminate a barely visible shimmer trades a minor cosmetic quirk for meaningfully faster burn-in risk.
Run periodic checks
Running the Burn-in mode above every few months on an OLED device gives you an early read on whether burn-in is developing, while it's still faint, rather than discovering it only once it's obvious during normal content.
Why LCD, LED, and OLED panels fail differently
| Panel type | Dead / stuck pixel risk | Burn-in risk |
|---|---|---|
| Standard LCD | Present, tied to transistor manufacturing defects | Effectively none, since a shared backlight sits behind all pixels |
| LED-backlit LCD | Same as standard LCD | Effectively none, same reasoning as standard LCD |
| OLED | Present, though modern manufacturing has reduced rates significantly | The primary long-term risk, since each pixel is individually lit and wears with use |
| AMOLED | Present, similar profile to OLED | Same underlying risk as OLED, common on phone displays |
Testing before you buy: new, refurbished, and used
| Source | What a defect typically means |
|---|---|
| New, boxed retail | Almost always covered by the retailer's standard return window regardless of the manufacturer's own pixel policy threshold. |
| Certified refurbished | Refurbishment programs generally test and reject panels with visible defects before resale, so a confirmed defect is worth raising directly with the refurbisher's own warranty terms. |
| Private sale, used | No warranty applies in most cases. A defect found during an in-person or video-call test becomes a negotiating point on price rather than a warranty claim. |
| Open-box or clearance | Often sold with a shorter or excluded pixel-defect warranty, so testing immediately upon arrival matters more than with a standard new purchase. |
For a private sale or marketplace purchase where an in-person test isn't possible, asking the seller to run this tool on a video call, holding the camera close enough to see the full panel on each test color, is a practical way to check before money changes hands.
Pixel defects vs. related terms people search for
LCD tester vs. dead pixel test
“LCD tester” is often used as a broader, informal term covering everything from pixel checks to uniformity and color accuracy, while “dead pixel test” usually refers specifically to the pixel and subpixel defect check this tool's Dead / Stuck Pixel mode performs.
Burn-in checker vs. image retention
Image retention is a temporary, usually LCD-specific effect where a very recently displayed static image briefly lingers before fading within minutes. Burn-in is permanent and specific to OLED and AMOLED panels. A “burn-in checker” like the mode above is testing for the permanent condition, not temporary retention.
Screen tear test vs. frame drop
Tearing is a visual split within a single frame due to sync mismatch. A dropped or stuttering frame is a separate performance issue, where a frame is skipped or delayed entirely rather than displayed incorrectly. The Screen Tearing mode above tests specifically for the split-frame symptom, not general performance stutter.
PC screen test vs. monitor test screen
Both phrases are typically used to describe the same general activity, using a full-screen tool like this one to inspect a display for defects, regardless of whether the display is a laptop panel, a desktop monitor, or an external screen.
Software pixel-fixing tools vs. this test
What this test does
Diagnoses. It shows you solid colors so you can visually locate and identify a dead pixel, stuck pixel, burn-in patch, or tearing artifact. It doesn't attempt to repair anything, since a genuine hardware defect can't be fixed by any software.
What dedicated pixel-fixing software does
Attempts a repair on stuck pixels specifically, by flashing rapid, high-frequency color changes at the exact defect location for an extended period, automating the manual rapid-cycling technique described earlier at a speed no person can replicate by hand.
Why you'd still want both
A diagnostic test tells you what you're dealing with and exactly where it is. Fix software only has a real chance at helping with stuck pixels, so testing first, with this tool, avoids wasting time running fix software against what's actually a permanent dead pixel or burn-in, neither of which will respond.
A caution on unverified software
Because pixel-fixing tools involve flashing rapid light patterns, stick to well-reviewed, established options rather than obscure downloads, and stop immediately if you experience any discomfort, since rapid flashing patterns are a known trigger for photosensitive reactions in a small percentage of people.
Where dead and stuck pixels actually come from
A single display panel contains millions of individual subpixels, each with its own microscopic transistor controlling exactly how much current reaches it. On an LCD panel, that transistor is part of a thin-film transistor, or TFT, array etched onto glass in a cleanroom environment where even a speck of dust or a momentary voltage fluctuation during manufacturing can damage or disable a single transistor among millions. OLED panels replace the backlight-plus-liquid-crystal structure with individually emissive diodes, but the same basic manufacturing risk applies: at the scale of a modern display, achieving true zero-defect yield across every single subpixel is not economically or physically realistic, which is exactly why manufacturers publish tolerance policies rather than zero-defect guarantees as a baseline standard.
This also explains why defects cluster statistically near panel edges and corners rather than distributing perfectly evenly. Manufacturing processes like photolithography and etching are more prone to small inconsistencies at the boundary of a production batch or wafer, the same reason edge pieces in many precision manufacturing processes carry a slightly higher defect rate than pieces cut from the center. It is part of why the step-by-step testing routine above specifically calls out checking corners and edges rather than assuming a clean center-of-screen scan is sufficient.
It also explains the difference between a dead pixel and a stuck pixel at the transistor level. A dead pixel's transistor has failed in a way that cuts off power delivery entirely, an unrecoverable hardware failure. A stuck pixel's transistor is still functioning, but a manufacturing defect, contamination, or a minor electrical fault has left it delivering current to only one subpixel color rather than responding to the full range of signals it should. That distinction, a total hardware failure versus a partial, sometimes-recoverable one, is the entire reason pixel-fixing techniques and software work on some defects and not others, and it's worth keeping in mind when deciding how much time to spend attempting a manual fix before accepting a result and moving to a warranty or return process instead.
Which mode to run first, and how long a full test should take
Start with Dead / Stuck Pixel mode, since it's the fastest to run and covers the most common defect type. A careful full-screen scan across all five colors, moving methodically rather than glancing quickly, takes most people two to four minutes on a single display, longer on a larger 4K panel where more screen area needs covering at the same visual density.
Move to Burn-in mode next if you're testing an OLED or AMOLED device, but skip it entirely for standard LCD panels, since burn-in is structurally not possible on a shared-backlight display and testing for it wastes time without providing any useful information. This mode only takes thirty seconds to a minute once the room is properly dimmed, since you're looking for the presence or absence of a specific pattern rather than scanning methodically.
Finish with Screen Tearing mode, which takes under a minute, since tearing during motion is either immediately visible or it isn't; there's no methodical scanning required the way there is for pixel defects. A full three-mode test, done properly, takes most people under five minutes total, making it practical to run immediately upon unboxing a new display, right before a return window closes, or as a quick periodic check on a device you already own.
If you're short on time and can only run one mode, Dead / Stuck Pixel mode is the highest-value choice for most situations, since pixel defects are the most commonly disputed issue in warranty and return conversations, while burn-in and tearing are typically either obviously present during normal use already or not relevant to the specific panel technology you're testing.
Display and pixel terms explained
Subpixel
One of the three individual red, green, or blue light elements that together make up a single visible pixel on a display.
TFT array
The grid of thin-film transistors on an LCD panel that individually controls each subpixel's brightness, manufactured as a single etched layer across the whole display.
Panel grade / bin
A manufacturing quality classification assigned to a panel based on how many defects it has, with higher grades commanding a price premium for stricter defect tolerance.
Refresh rate
How many times per second a display redraws its image, measured in Hz. A mismatch between refresh rate and incoming frame rate is the underlying cause of screen tearing.
V-Sync / G-Sync / FreeSync
Software and hardware technologies that synchronize a display's refresh rate with the incoming frame rate specifically to prevent screen tearing.
Image retention
A temporary version of burn-in, most common on LCD panels, where a recently displayed static image briefly lingers before fading within minutes, unlike permanent OLED burn-in.
Pixel pitch
The physical distance between adjacent pixels, which determines how visible an individual pixel defect is likely to be at normal viewing distance.
Return merchandise authorization (RMA)
The formal process, usually involving a case number, for returning or exchanging a defective device with a manufacturer or retailer.
Common questions
What is the difference between a dead pixel and a stuck pixel?
A dead pixel has lost power completely and shows black on every background, with no exceptions. A stuck pixel still receives power but is locked to a single color, most commonly red, green, or blue, and that color persists no matter what background you display behind it.
How do I test for dead pixels?
Switch to Dead / Stuck Pixel mode above, go full screen, and cycle through white, black, red, green, and blue using the swatches or the left and right arrow keys. Scan the entire screen methodically on each color, including corners and edges, since defects can appear anywhere on the panel.
Can a stuck pixel fix itself?
Sometimes. Stuck pixels are occasionally caused by a transistor that is temporarily stuck rather than permanently damaged. Rapidly cycling colors, gentle pressure massage techniques, or dedicated pixel-fixing software can occasionally free a stuck subpixel. A true dead pixel, which has lost power entirely, does not respond to these techniques.
How many dead pixels are acceptable on a new monitor?
There is no single industry standard. Acceptable defect counts vary by manufacturer, panel grade, and sometimes by region, ranging from a strict zero-dead-pixel policy on premium panels to several permitted defects on standard consumer-grade panels. Check the specific manufacturer's dead pixel policy for your exact model before assuming a defect qualifies for replacement.
How do I check for OLED burn-in?
Switch to Burn-in mode, go full screen in a dim room, and look for any faint shape, outline, or discoloration that stays visible against the solid black field. Common burn-in patterns include a taskbar, a navigation bar, a static logo, or a paused video's letterbox bars.
How do I test for screen tearing?
Switch to Screen Tearing mode and go full screen. Watch the moving reference line during motion. A clean, single line indicates no tearing. A visibly split or offset line, where the top and bottom sections appear misaligned, indicates tearing, which is a synchronization issue rather than a hardware defect and is usually fixable through V-Sync, G-Sync, or FreeSync settings.
Is this the same as the Color Screen Test tool?
They share the same underlying full-screen color mechanism, but this tool is purpose-built for pixel and panel diagnostics, with a dedicated three-mode selector for dead/stuck pixels, burn-in, and screen tearing, plus keyboard navigation for faster scanning. If you just need a specific solid color for a background or general test, the Color Screen Test tool works too.