Dead Pixel on a TV
Updated
To test a TV for dead pixels, open this page in the TV’s web browser and start the test below. No browser? Plug in a laptop by HDMI and run the test on it full screen.
Six full-screen colors. Click, tap or press an arrow key to move to the next one.
How do I test a TV for dead pixels?
Turn off motion smoothing and any eco mode first, so the picture is steady and bright. Then follow these steps.
- Open this page in the TV browser, or mirror a laptop to the TV over HDMI.
- Start the test. On a TV browser, the arrow buttons on the remote usually change the color.
- Stand close to the screen and scan it in strips, top to bottom.
- Check any dot again on each color before you decide what it is.
How big is one pixel on a TV?
Smaller than you might think. On a 55 inch 4K TV each pixel is about 0.32 mm across. You may need to stand close to see a single dead one.
Is it a dead pixel or something else?
A dead pixel is one sharp black dot on every bright color. A colored dot is usually stuck, and the stuck pixel fixer can sometimes free it.
Cloudy patches on a dark picture come from the backlight. Run the black screen test to check them.
What should I do about a dead pixel on a new TV?
Photograph the dot on a solid color, close enough to see it clearly. Then contact the seller before the return window closes, and check the maker’s pixel policy.
Our guide to screen returns covers what to keep and what to ask.
What pixel faults can a TV have?
Each pixel is made of red, green and blue parts. A fault in any of them shows up as one of these:
- Dead pixel: a black dot that stays dark on every color.
- Stuck pixel: a red, green or blue dot that stays lit.
- Hot pixel: a white dot that stays fully lit, easiest to see on black.
- Dead line: a full row or column of pixels, usually a panel or cable fault.
How do I test a TV with a USB stick?
If the TV has no web browser and no laptop is handy, use plain color pictures instead:
- Make five pictures at the TV’s resolution, such as 3840 × 2160, in black, white, red, green and blue.
- Save them as PNG files on a USB stick.
- Plug the stick into the TV and open the pictures in its media player.
- Step through each color and scan the screen up close.
Turn off any zoom or picture size setting, so each picture fills the screen exactly.
How do I check an OLED TV?
OLED pixels make their own light, so there is no backlight to bleed. Check for dead pixels the same way, then look for faint marks on a plain gray screen.
Faint shapes on gray can be image retention from a logo or menu. OLED TVs run a pixel refresh while switched off, so leave the TV in standby and check again the next day.
What is clouding or backlight bleed on a TV?
On LCD and LED TVs, light from the backlight can leak through unevenly. It shows as cloudy patches or bright corners on a black screen in a dark room.
Some unevenness is normal on large LCD panels. If it shows in normal films or shows, report it to the seller with a photo from your seat.
Can a stuck pixel on a TV be fixed?
Sometimes. A stuck pixel fixer flashes colors fast over the spot, which can free a pixel that is stuck on. Run our stuck pixel test for 10 to 20 minutes through the TV browser or a laptop.
A dead pixel that stays black on every color rarely comes back. Do not press on the screen, as that can damage the panel.
How do I test a used TV before buying?
Ask the seller to switch it on before you pay. Then check these points:
- Open this page in the TV browser and run the test on each color.
- Play something dark to look for bleed or clouding.
- Try every HDMI port and the remote buttons.
- Check the model number on the back matches the listing, and the size on our TV size chart.
Does the warranty cover a dead pixel on a TV?
It depends on the maker and on how many faulty pixels there are. TV makers do not always publish a pixel policy, so ask the support team directly.
Have the model, serial number, receipt and photos ready. Our dead pixel policy guide shows how monitor makers count faults, which helps you describe yours.
Is the dot on the screen or on the glass?
Wipe the screen with a dry microfiber cloth first. Dust, a speck of food or a smudge can look just like a dead pixel.
If the dot moves when you look from the side, it is on the surface. A real pixel fault stays in place from every angle.
How close do I need to stand to see a dead pixel?
Closer than you sit to watch. On a 55 inch 4K TV, a single pixel becomes too small to see beyond about 42.9 in (109.0 cm)109.0 cm (42.9 in).
Stand within that distance and scan the screen in strips. On a 1080p TV the pixels are twice as wide, so they show from further away.
Can I test a TV in the shop before buying?
Often, yes. Ask staff to open the TV’s web browser and load this page, or show a plain white and black picture.
Display TVs run bright for hours, so check the one you take home as well. Run the test again on the day it is delivered.
Questions
Can I test a TV with my phone?
Only by casting or mirroring your phone to the TV. Then open this page on the phone and start the test full screen.
Does a dead pixel test harm my TV?
No. It only shows plain colors, like any other picture.
Should I test a new TV in a dark room?
Yes, for bright dots and bleed. Dark dots are easier to see on white with the lights on.
How many dead pixels are acceptable on a TV?
There is no single rule, as each maker sets its own. Report any dead pixel you can see from your seat to the seller.
Can a dead pixel on a TV get worse?
A single dead pixel usually stays the same. If more appear or a line forms, contact the maker, as the panel may be failing.
Can I run a dead pixel test without a TV browser?
Yes. Plug a laptop into the TV with an HDMI cable, mirror the screen and start the test full screen. A USB stick with solid color pictures also works.
Is a bright patch the same as a stuck pixel?
No. A soft glow near the edges on a dark picture comes from the backlight, not a pixel. A pixel fault is one sharp dot.
Does a dead pixel matter from the sofa?
Often not. On a large 4K TV each pixel is a fraction of a millimeter. One dead pixel can be hard to see from a few meters away.