Screen condition is the single most expensive thing to get wrong on a used phone or tablet, and it is also where buyers panic the most. Most people lump every display flaw under “the screen looks off,” but dead pixels, burn-in, ghosting, and backlight bleed have different causes, different fixes, and very different consequences for value. This guide defines each defect, shows you how to surface it during inspection, and tells you which ones are permanent so you can evaluate a screen with confidence instead of walking away from a good deal.
For the full picture on how screen wear fits into overall device condition, see Swappa’s Used Electronics Condition Grades guide.
Quick Answer
The four common screen defects are dead pixels (permanently dark or stuck dots), OLED burn-in (faint permanent ghost images from static content), ghosting or image retention (a temporary afterimage that fades), and backlight bleed (light leaking around the edges of an LCD in the dark). Dead pixels and burn-in are permanent. Ghosting is usually temporary. Backlight bleed is a fixed physical trait of the panel that will not get worse. Test any used display with solid full-screen colors (white, black, red, green, blue) at full brightness before you buy.
The Four Most Common Screen Defects Defined
Screen defects fall into four buckets. Knowing which one you are looking at tells you whether it is a walk-away problem or a minor negotiating point.
Dead pixels. A dead pixel is a single point on the display that no longer lights up, so it stays black regardless of what is on screen. A related issue, the stuck pixel, is locked on one color (red, green, or blue) and shows as a bright dot. Dead pixels are most visible against a solid white or colored background. A single dead pixel near the edge is easy to miss. A cluster in the center is not.
OLED burn-in. Burn-in is uneven aging of the individual pixels on an OLED or AMOLED panel. When static elements (a navigation bar, a keyboard, a status bar, a channel logo) stay on screen for hundreds of hours, those pixels dim faster than the ones around them. The result is a faint permanent ghost of that element that shows up on solid colors, most often gray. Burn-in only affects OLED and AMOLED screens, not traditional LCDs.
Ghosting (image retention). Ghosting, also called image retention, looks like burn-in but is temporary. A faint afterimage of the previous content lingers for a few seconds or minutes, then fades on its own. It is common on both LCD and OLED panels and does not indicate permanent damage. The key difference from burn-in is that ghosting goes away.
Backlight bleed. Backlight bleed is light leaking unevenly around the edges or corners of an LCD screen, visible as brighter cloudy patches when the display shows a dark image in a dim room. It is caused by the backlight not being perfectly sealed behind the LCD layer. OLED screens do not have a backlight, so they do not get bleed. Mild bleed is common and normal on LCDs.
How To Test A Display For Dead Pixels And Bleed
You do not need special equipment to inspect a screen. You need solid full-screen colors, full brightness, and a couple of minutes. This is a core part of a full device check, covered end to end in How to Test a Used Device.
Set brightness to maximum and turn off any auto-brightness or dark mode. Then display each of these full-screen colors one at a time: pure white, pure black, red, green, and blue. A free pixel-test website or app cycles through them for you.
- White and light colors surface dead pixels (black dots) and dust or debris under the glass.
- Red, green, and blue surface stuck pixels, which will be dots showing the wrong color.
- Solid black in a dark room surfaces backlight bleed on LCDs (bright cloudy edges) and helps confirm whether an OLED has any burn-in shadow.
Look at the whole panel, including the corners and edges where bleed and edge dead pixels hide. Tilt the device slightly to check for pressure marks or discoloration that only appear at an angle. If you are buying in person, do this test before anything else, since a bad panel is a deal-ender.
When you are shopping remotely, ask the seller for a photo or short video of the screen showing a solid white and a solid black image. This is standard practice and a reasonable seller will not push back. For the wider set of remote-buying precautions, see How to Buy Used Electronics Safely.
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Spotting Burn-In And Ghosting On OLED Screens
Burn-in and ghosting look nearly identical at first glance, and confusing them is the most common mistake buyers make. The test that separates them is time.
To check an OLED or AMOLED device for burn-in, display a solid medium-gray or a solid white image at full brightness for at least thirty seconds. Then look for faint darker outlines of interface elements: a keyboard shape at the bottom, a status bar across the top, or app icons in a grid. If a ghost image is visible and stays put no matter what content you switch to, that is burn-in, and it is permanent.
Ghosting behaves differently. If you switch to a new solid color and the leftover image fades away within a few seconds to a minute, that is image retention, not burn-in. Retention is temporary and does not affect the device long term.
Burn-in risk is higher on older OLED phones, devices used heavily for navigation or gaming, and screens run at high brightness for long stretches. It is much rarer on tablets and laptops that spend time in sleep. Light burn-in near the status bar is common on well-used OLED phones and is often only visible on solid gray, so weigh how noticeable it actually is during normal use before you rule a device out.
Which Defects Are Permanent And Which Are Not
This is the part that turns panic into a decision. Two of these defects are permanent, one is temporary, and one is a fixed physical trait that will not get worse.
| Defect | Cause | Permanent? | How to test | Effect on value |
|---|---|---|---|---|
| Dead pixel | Failed pixel transistor | Yes | Solid white and colored screens at full brightness | Minor for a single edge pixel; larger for center clusters |
| Stuck pixel | Pixel locked on one color | Sometimes | Solid red, green, blue screens | Minor; occasionally fixable with pixel-cycling tools |
| OLED burn-in | Uneven pixel aging from static content | Yes | Solid gray or white for 30+ seconds | Moderate; depends on visibility during normal use |
| Ghosting (image retention) | Temporary pixel charge lag | No | Switch solid colors, watch it fade | None if it fully fades |
| Backlight bleed | Light leaking past the LCD edge | No (does not worsen) | Solid black in a dark room | Minor to moderate depending on severity |
A few practical notes on that table. Dead pixels are physical failures and do not heal, though a single one at the edge is easy to live with. Stuck pixels can sometimes be revived with a pixel-cycling app, so they are worth a small discount rather than a hard pass. Burn-in never reverses. Ghosting that fully fades is a non-issue. Backlight bleed does not spread or worsen over time, so a device with mild, tolerable bleed today will look the same in a year.
One thing that is never just a screen defect: a cracked screen. A crack can spread, let moisture in, and kill the touch layer. On Swappa, cracked glass is a hard non-listable condition, so a listing that passes staff review has already cleared that bar. For where the line sits between surface flaws and real damage, see Cosmetic vs. Functional Damage.
How Screen Defects Affect Condition And Value
Screen condition is one of the biggest inputs into what a used device is worth, so it maps directly onto how devices are graded and priced. Swappa’s condition grades are defined by wear: Mint means no signs of wear, Good means minor wear, Fair means noticeable wear, and every listed grade has to be fully functional. A visible screen defect typically moves a device down a grade, and that grade difference is where the price difference lives. For how those grades translate to real numbers, defer to the Used Electronics Condition Grades guide rather than fixed dollar figures, since prices move by model and vary as ranges.
The practical takeaway for buyers: a single edge dead pixel or mild backlight bleed is a legitimate negotiating point, not a reason to walk. Noticeable center-screen dead pixels, obvious burn-in, or a cracked screen are different, and those should either drop the price meaningfully or send you to another listing.
Buying on Swappa removes most of the guesswork from this. Real people approve listings before they go live, cracked-glass and water-damaged devices are non-listable, and sellers must disclose condition accurately. If a device shows up not as advertised, the buyer is entitled to a refund, and Swappa’s fees (3% seller fee plus 3% buyer fee already included in the listing price) are lower than typical auction-site fees. Payments run through PayPal with buyer and seller protection, or Stripe for select sellers.
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FAQ
What is the difference between OLED burn-in and ghosting?
Burn-in is permanent uneven aging of OLED pixels caused by static content staying on screen for a long time, and it leaves a faint image that never goes away. Ghosting, also called image retention, is a temporary afterimage that fades on its own within seconds to a minute. If the leftover image disappears when you switch content, it is ghosting, not burn-in.
Are dead pixels permanent on a used phone?
Yes. A dead pixel is a physical failure of that point on the display and will not repair itself. A stuck pixel, which shows one wrong color rather than staying black, can sometimes be revived with a pixel-cycling app, but a true dead pixel is permanent. A single dead pixel at the edge is usually easy to live with, while a cluster near the center is more serious.
How do I test a used device screen for defects before buying?
Set the display to full brightness with auto-brightness and dark mode off, then show solid full-screen colors one at a time: white, black, red, green, and blue. White surfaces dead pixels, colored screens surface stuck pixels, and solid black in a dark room surfaces backlight bleed on LCDs. For OLED devices, hold a solid gray or white image for at least thirty seconds and look for faint permanent outlines.
Is backlight bleed a serious problem on a used screen?
Usually not. Backlight bleed is light leaking around the edges of an LCD panel and only shows up as brighter patches when a dark image is displayed in a dim room. It does not spread or get worse over time, and mild bleed is common and normal. Only heavy, obviously distracting bleed is worth a meaningful discount.
Do screen defects affect a used device’s condition grade and value?
Yes. A visible screen defect typically moves a device down a condition grade, and that grade difference drives the price difference. Minor issues like a single edge dead pixel or mild backlight bleed are small negotiating points, while obvious burn-in or center dead pixels reduce value more. On Swappa, cracked screens are non-listable entirely, so they never receive a grade.
Can a phone with a cracked screen be listed on Swappa?
No. Cracked glass is a hard non-listable condition on Swappa, not a low grade, because a crack can spread, admit moisture, and damage the touch layer. Real people approve listings before they go live, so an approved listing has already cleared that bar. If you own a device with a cracked screen, the practical move is to buy a verified replacement.
The Bottom Line
Screen defects are not all created equal. Dead pixels and OLED burn-in are permanent, ghosting is temporary and harmless once it fades, and backlight bleed is a fixed panel trait that will not get worse. Test any used display with solid full-screen colors at full brightness, judge each flaw by how noticeable it actually is in normal use, and treat minor issues as negotiating points rather than deal-breakers.
When you buy on a platform where listings are staff-reviewed and cracked or water-damaged devices are non-listable, the screen question becomes about preference and price, not risk.
