You just bought a used MacBook — or your new one arrived and you want to check it before the return window closes. Either way, you need to know exactly what you're looking at. Retina displays pack so many pixels per inch that defects are tiny, and the notch cutout on newer MacBook Pros creates blind spots in your inspection if you're not careful.
Here's the complete process: how to run the test, what MacBook pixel defects actually look like, and what Apple will do about them.
How to Run the Dead Pixel Test on a MacBook
MacBook screens need to be in true full-screen mode for an accurate test. The key requirement: use Safari, not Chrome or Firefox.
Chrome's full-screen still surfaces the menu bar on cursor movement, which can mask defects along the top edge. Safari's full-screen mode (activated with Control + Command + F) completely hides the menu bar and Dock for a clean, uninterrupted view.
Here's the step-by-step process:
- Open Safari and navigate to deadpixelcheck.com.
- Darken your room. Ambient light reflecting off the screen makes small defects much harder to spot. Close blinds, turn off overhead lights.
- Press Control + Command + F to enter full-screen mode. Alternatively, go to View > Enter Full Screen.
- Click each color button on the tool — red, green, blue, white, black — and let it fill your screen.
- Scan the full display on each color. Move your eyes methodically from top-left to bottom-right. Pay special attention to corners and edges where defects cluster most often.
- Check the notch zone on MacBook Pro 14"/16" — the pixels immediately adjacent to the notch cutout can hide defects against the black bezel.
Pro Tip: Test at Multiple Brightness Levels
Run the test twice — once at full brightness, once at about 50%. Some display anomalies (particularly brightness uniformity issues and IPS bleed) only appear at specific brightness levels. Dead pixels will be visible at any brightness, but this gives you a complete picture of the panel's health.
What MacBook Pixel Defects Actually Look Like
MacBook Retina displays have very high pixel density — 224 ppi on MacBook Air models, 254 ppi on the 14" and 16" MacBook Pro. This means individual pixels are tiny. You need to look for small anomalies, not obvious blotches.
Here's what each defect type looks like:
- Dead pixel: A tiny black dot that appears on every color screen — red, green, blue, and white. It literally does not turn on. These are hardware failures and cannot be fixed with software.
- Stuck pixel: A dot that glows a fixed color (usually red, green, or blue) regardless of what the screen displays. On a red screen you might not notice it — but it will stand out on blue, and especially on black. Stuck pixels sometimes resolve on their own or with pixel-cycling software.
- Hot pixel: A pixel stuck permanently "on" — usually appears white or very bright. Most visible on the black screen.
- IPS backlight bleed: Not a pixel defect, but a common LCD characteristic. Appears as soft, glowing patches at the corners or edges, most visible on a dark screen in a dark room. This is a panel-level issue, not individual pixels.
- Pressure damage: A cluster of discolored or dead pixels, usually surrounded by a visible distortion pattern. Common in used laptops where the lid has been closed with something on the keyboard.
Don't Confuse Dust with Dead Pixels
Before diagnosing a dead pixel, clean the screen. A speck of dust between the display glass and the panel can look exactly like a dead pixel from a normal viewing distance. Use a microfiber cloth to gently clean the screen — if the dot moves or disappears, it was dust. If it stays fixed in position, you have a pixel defect.
Dead Pixel vs Stuck Pixel on a Retina Display
The distinction matters because stuck pixels sometimes resolve without any intervention, while true dead pixels almost never self-heal.
On MacBook Air and MacBook Pro LCD panels (Liquid Retina and Liquid Retina XDR), a dead pixel is one where the thin-film transistor (TFT) controlling that pixel has failed. It can no longer receive a signal to open the liquid crystal, so no backlight passes through — the result is a permanently black dot. Hardware failure, no fix without screen replacement.
A stuck pixel is one where the liquid crystal is frozen in one state — either fully open (transmitting light continuously) or stuck at a specific color channel. Stuck pixels on LCD panels sometimes free up after running a pixel-cycling video for 30–60 minutes. Our built-in stuck pixel fixer on the homepage cycles colors at high frequency to try to unstick frozen crystals.
Quick field test: run the black screen. A dead pixel doesn't appear — it's already off, just like every other off pixel. A stuck pixel glows a color. If you see a bright dot on the black screen, it's stuck, not dead.
Buying a Used MacBook? Run This Full Checklist
If you're purchasing a used or refurbished MacBook, pixel testing is just one part of the display inspection. Run all of these before handing over money or letting a return window expire:
- ✓ Dead pixel test (run now at deadpixelcheck.com)
- ✓ Backlight bleed test — black screen, dark room, look for corner glow
- ✓ Color uniformity — white screen, check for patches that look yellower or cooler
- ✓ Brightness uniformity — white screen at full brightness, look for dark patches
- ✓ Pressure damage check — look for any pixel clusters that might indicate impact or lid pressure
- ✓ Physical inspection — check the display frame for cracks, dents, or separation that could indicate past damage
- ✓ Hinge test — open and close the lid several times; it should feel smooth and hold at any angle without flopping
- ✓ True Tone / P3 wide color — go to System Settings > Displays to verify True Tone and P3 are listed as supported
Apple's Pixel Defect Policy for MacBooks
Apple doesn't publish a specific minimum dead pixel count for Mac displays the way some third-party monitor manufacturers do. Their approach is case-by-case evaluation based on:
- The number and type of defects (dead vs stuck vs hot)
- Location — center-of-screen defects are weighted more heavily than edge defects
- Impact on normal use — a defect visible during normal work tasks is a stronger claim
- Whether the display is within the standard 1-year limited warranty or AppleCare+
In practice, a single dead pixel in the central 75% of a MacBook display — visible during everyday use — is typically sufficient for a warranty display replacement. Apple technicians at Genius Bar appointments will evaluate the defect in person.
If you bought the MacBook within the last 14 days from Apple directly or Apple Authorized Resellers, you can also request a full unit return rather than a repair, even for a single dead pixel. Use that window.
What to Do If You Find a Defect
Found something on the test? Here's your decision tree:
If the MacBook is new (within 14 days): Contact Apple directly for a return and replacement. Don't go through repair — request a new unit. You're within the standard return window.
If the MacBook is new (within 1 year, no AppleCare): Book a Genius Bar appointment. Bring your phone photo of the defect, not just a description. Apple will evaluate and typically covers display defects under the standard limited warranty.
If you have AppleCare+: AppleCare+ covers accidental damage with a service fee, but manufacturing defects (dead pixels) are covered at no charge under the underlying warranty terms.
If the MacBook is used and out of warranty: Get a repair quote from Apple and compare it to independent repair shops. Display replacements for MacBook models run $300–$700 depending on the model. For a heavily used machine, weigh the repair cost against the machine's value.
If the pixel is stuck, not dead: Try our stuck pixel fixer tool first. Run it for 30–60 minutes on the affected area. It won't fix a true dead pixel, but it resolves stuck pixels in many cases.
Keep Your MacBook Screen Clean
A clean screen makes pixel defects easy to spot — and a dirty one creates false positives. Screen Mom Screen Cleaner is a top-rated kit with a microfiber cloth that's safe for Retina displays and won't leave streaks.
Screen Mom Screen Cleaner Set → Amazon affiliate link