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Dead Pixel Test App: Check Your LCD Screen for Defective Pixels
Dead pixel tester is a handy online tool that helps you locate non-functioning or defective pixels on your digital screen. It displays various solid colors, making it easier to spot pixels that either don’t change color or remain dark.
Our dead pixel repair tool is designed to repair stuck pixels on your display. It quickly cycles through colors or uses flashing patterns to stimulate the pixel, encouraging it to start working properly again.
White Screen
- What to Look For: Dead pixels appear as small black dots on the white screen because they fail to emit any light. Stuck pixels, which are pixels that are permanently lit in one or two colors, may also stand out, appearing as colored dots (red, green, or blue).
- Identifying Dead Pixels: Carefully scan the screen for any black spots that don't match the surrounding white color. These are dead pixels.
- Identifying Stuck Pixels: Look for bright red, green, or blue spots that stand out against the white background. This indicates stuck pixels.
This tool works on all devices, including desktops, laptops, tablets, and smartphones. It works on all digital display types including TFT, LCD, LED monitors, OLED, AMOLED phone displays.
No need to download or install anything. Our app works within the browser.
A dead pixel is a pixel on a digital display that stays unlit, showing up as a black dot. This occurs when the sub-pixels (red, green, blue) fail to receive power or a signal, preventing them from displaying any color and distorting the display image.
Common types of dead pixels include:
- Dead Pixels: Completely black, unlit pixels.
- Stuck Pixels: Pixels stuck in one color (red, green, or blue).
- Hot Pixels: Pixels that are always on, typically white.
How it works
Dead Pixel Test
This tool offers a straightforward, step-by-step approach to checking for dead pixels. Upon clicking the “Start Dead Pixel Test” button, the tool enters full-screen mode, allowing users to thoroughly examine their screens. The screen cycles through a series of full-screen colors—white, black, red, green, blue, yellow, cyan, and magenta—each displayed one at a time.
Users can manually navigate through these colors using the “Next” and “Previous” buttons, allowing them to carefully inspect each color for any anomalies. To assist users in identifying dead pixels, a zoom circle is attached to the cursor making it easier for users to focus on a specific area.
Dead Pixel Repair
Dead Pixel Repair works by rapidly cycling through RGB and CMYK colors. You can control the speed of color cycling. This is done on full screen so the dead pixels can reactivate the stuck pixel.
This technique only works if a pixel has been temporarily stuck. If the hardware is damaged, you’ll need to replace the display unit.
There are several ways to repair dead pixels:
- Pixel Cycling: Rapidly cycles colors to stimulate stuck pixels.
- Noise Patterns: Introduces random pixel changes to dislodge stuck pixels.
- Inversion Techniques: Switches pixel colors to their opposites to “unstick” pixels.
- Color Sweep: Gradually transition colors to identify and fix stuck pixels.
- Flashing Box: Creates a small, rapidly flashing box to re-energize stuck pixels.
- Gradient Sweep: Displays gradient transitions to reveal subtle pixel issues.
We use the pixel cycling technique which works relatively well.
How to Check for Dead Pixels on Each Color Screen
- White Screen
- What to Look For: Dead pixels appear as small black dots on the white screen because they fail to emit any light. Stuck pixels, which are pixels that are permanently lit in one or two colors, may also stand out, appearing as colored dots (red, green, or blue).
- Identifying Dead Pixels: Carefully scan the screen for any black spots that don’t match the surrounding white color. These are dead pixels.
- Identifying Stuck Pixels: Look for bright red, green, or blue spots that stand out against the white background. This indicates stuck pixels.
- Black Screen
- What to Look For: On a black screen, dead pixels are harder to spot, but stuck or bright pixels become more visible. Bright pixels, which are pixels permanently turned on, appear as small white or colored dots.
- Identifying Stuck Pixels: Look for any bright spots that contrast with the black background. They are usually stuck.
- Identifying Bright Pixels: Any white or colored dot against the black screen is a bright pixel.
- Red Screen
- What to Look For: On a red screen, dead pixels will appear as black dots, while stuck pixels may appear as small spots of blue or green.
- Identifying Dead Pixels: Scan for any black spots that interrupt the solid red color.
- Identifying Stuck Pixels: Look for spots that are not red, particularly blue or green, indicating stuck pixels.
- Green Screen
- What to Look For: On a green screen, dead pixels show up as black dots, and stuck pixels may appear as red or blue.
- Identifying Dead Pixels: Look for any black spots that are inconsistent with the green background.
- Identifying Stuck Pixels: Notice any red or blue spots, which indicate stuck pixels.
- Blue Screen
- What to Look For: Dead pixels on a blue screen appear as black dots, while stuck pixels may appear as red or green.
- Identifying Dead Pixels: Black spots on the blue screen indicate dead pixels.
- Identifying Stuck Pixels: Look for any red or green spots that disrupt the blue color, indicating stuck pixels.
- Yellow Screen
- What to Look For: Yellow screens can highlight dead pixels as black spots, and stuck pixels may show as small red or blue dots.
- Identifying Dead Pixels: Black dots on the yellow screen suggest dead pixels.
- Identifying Stuck Pixels: Red or blue spots are signs of stuck pixels.
- Cyan Screen
- What to Look For: Dead pixels appear as black dots on a sea green background, while stuck pixels may show as red or blue.
- Identifying Dead Pixels: Look for black spots that stand out against the sea green color.
- Identifying Stuck Pixels: Notice any red or blue spots, which are indicators of stuck pixels.
- Magenta Screen
- What to Look For: On the magenta screen, dead pixels will appear as black dots, and stuck pixels may appear as green or blue.
- Identifying Dead Pixels: Any black spot on the magenta background is a dead pixel.
- Identifying Stuck Pixels: Look for green or blue spots, which suggest stuck pixels.
How to fix Dead Pixels
In addition to identifying dead or stuck pixels, the Dead Pixel Checker tool provides a possible solution. When a problematic pixel is detected, users can click the “Fix Dead Pixel” button. This will activate a pixel jitter tool that quickly cycles through various full-screen colors (RGB + CMYK). The rapid color changes aim to stimulate stuck or dead pixels, potentially reviving them.
- How It Works: The pixel jitter tool forces the affected pixel to display a rapid sequence of colors, which can sometimes cause the pixel to reset and function correctly.
- Effectiveness: While this method may not work for every dead or stuck pixel, it can often revive pixels that are simply stuck in one color. For the best results, users should run the jitter tool for a few minutes and repeat the process if necessary.
Future Enhancements
The Dead Pixel Checker tool currently emphasizes color-based testing and pixel repair. However, upcoming updates will bring new features, including adjustable screen brightness and contrast settings. These improvements will help users more effectively identify and resolve dead pixels in different conditions.
Privacy and compatibility
Privacy is an important factor, and our tool does not gather any data from its users. It functions entirely within the browser session, which keeps your information safe.
Being fully web-based, the tool works with all major browsers that support JavaScript, allowing a broad audience to access it without needing any special requirements.
Frequently Asked Questions
- Can a dead pixel be fixed?
Sometimes, dead pixels are those that remain permanently off, showing up as black dots on the screen. Although they are generally seen as permanent issues, there are instances where they can be revived. Tools like the Pixel jitter function in our Dead Pixel Checker can help. This technique quickly cycles through colors to stimulate the pixel, and in some cases, it can restore its functionality.
- Is it okay to have a dead pixel?
It really depends on the individual and how many dead pixels are present. For many users, having one or two dead pixels may not be a big deal or even noticeable. However, if there are numerous dead pixels, it can significantly impact the viewing experience and might qualify for a warranty claim, depending on the display’s classification under the ISO 13406-2 standard.
ISO 13406-2 outlines acceptable levels of pixel defects in flat-panel displays. It classifies these defects and sets limits on the maximum number of allowable defects for each category.ISO 13406-2 is a standard that defines acceptable levels of pixel defects in flat-panel displays. It categorizes pixel defects into classes and specifies the maximum number of allowable defects for each class.
Key Points:
- Classes of Defects:
- Class 1: No pixel defects allowed.
- Class 2: Allows a limited number of defects, including dead, stuck, and hot pixels.
- Class 3: Permits more defects than Class 2.
- Class 4: Highest tolerance for defects.
Defect Categories:
- Type 1: Always lit (white) pixels.
- Type 2: Always unlit (black) pixels.
- Type 3: Stuck pixels (red, green, blue).
Example Allowances for Class 2:
Defect Type
Maximum Allowed
Type 1
2
Type 2
2
Type 3
5
Practical Application:
- Manufacturers: Use the standard to classify display quality.
- Consumers: Refer to it for warranty and quality assurance.
Mathematical Representation:
If 𝑁N is the total number of pixels, the defect rate 𝐷D for a given class can be expressed as:
𝐷=Number of Defects 𝑁D=N Number of Defects
For Class 2, if a display has 𝑁=1,000,000N=1,000,000 pixels:
𝐷Type 1=21,000,000=0.0002%DType 1=1,000,0002=0.0002%
- Classes of Defects:
- Is a dead pixel permanent?
Dead pixels are usually permanent, but sometimes they can be revived with pixel fixing techniques, such as those offered by our tool. If the pixel is merely stuck (constantly showing one color), it might be simpler to fix than a physically dead pixel.
- How much does it cost to fix dead pixels?
The cost to fix dead pixels can differ. If you use a software tool like our Dead Pixel Checker, you might be able to fix it for free. However, if the pixel can’t be repaired with software and it’s bothersome enough to warrant a screen replacement, the cost will depend on your device and whether it’s under warranty.
- Is one dead pixel noticeable?
The visibility of a dead pixel largely depends on where it is located and the resolution of your screen. On a high-resolution display, a single dead pixel can be hard to spot, particularly if it’s situated near the edge. In contrast, a dead pixel located near the center of the screen is likely to be more apparent.
- What causes dead pixels?
Dead pixels typically result from manufacturing defects, physical damage, or gradual wear and tear. They may also arise from electrical failures within the display.
- Can dead pixels spread?
Dead pixels themselves do not spread. However, if the cause is related to an underlying hardware issue, other pixels may become dead or stuck over time.
- Should I return the device with dead pixels?
The decision really depends on how bothersome the dead pixels are to you and whether they fall under the manufacturer’s warranty. If they are covered and you find them distracting, returning the device could be a good option. Many manufacturers have specific policies regarding dead pixels that clarify when a return or replacement is warranted.
- How can I prevent dead pixels?
While there’s no foolproof way to prevent dead pixels, treating your device with care, steering clear of extreme temperatures, and maintaining cleanliness can help minimize the risk.