Monitor Tests
Find dead pixels, check refresh rate and motion, test colors and backlight, and fill your screen with any color.
Pixel and panel tests
Dead Pixel Test
Fill the screen with pure colors, find dead and stuck pixels, and map them for a warranty claim.
Burn-In Test
Grey and color screens that reveal OLED burn-in and image retention, with a timed retention check.
Backlight Bleed Test
Show full screen black and dark grey to spot backlight bleed, IPS glow and clouding on an LCD.
TV Test Pattern
Color bars, brightness, contrast, sharpness and overscan patterns to set up any TV picture.
HDR Test
See whether HDR is on, which color range your screen covers and how bright its highlights get.
Stuck Pixel Fixer
Flash rapid colors over a stuck pixel to try to free it, with a box you can drag, resize and time.
4K Test
One pixel lines, fine text and a zone plate that show whether a screen really displays 4K.
Monitor Test
Step through 17 full screen patterns to check a monitor's pixels, colors, gamma and sharpness.
Projector Test Pattern
Focus stars, keystone grid, convergence and ANSI contrast patterns for setting up a projector.
Monitor Color Test
Color bars, gradients, gamma and saturation patterns that show banding, tints and clipped colors.
Color screens
Red Screen
A dim red screen light that keeps your night vision, plus pure red for checking pixels.
White Screen
A full white screen for light, cleaning and pixel checks, from warm 2700 K to cool 9300 K.
Black Screen
A pure black full screen that stays awake, for OLED, cleaning, dark rooms and backlight checks.
Blue Screen
Full screen blue for chroma key backdrops and pixel checks, plus fixes for the blue screen of death.
Green Screen
Chroma key green or pure green on any display, for keying, screen replacement and pixel checks.
Pink Screen
Soft, hot, deep or pastel pink full screen light for selfies, video calls, backdrops and room glow.
Purple Screen
Purple, violet and lavender full screen light for room glow, backdrops and color checks.
Orange Screen
Warm orange, amber and candlelight full screen glow with a dimmer and a sleep timer.
Yellow Screen
Pure yellow for pixel and tint checks, plus gold, lemon and mustard shades for warm light.
Grey Screen
Grey levels from 5 to 75% for checking uniformity, dirty screen effect, bands and burn in.
Rainbow Screen
A full screen rainbow: smooth color cycle, flowing bands or still bars, with a speed control.
Color Screen
Fill your display with any color: 12 test colors, a color picker and hex codes, with auto cycling.
Motion and refresh rate
UFO Test
Watch the same craft at full, half and quarter frame rate to judge motion blur and smoothness.
FPS Test
Compare 30, 60, 120 fps and your maximum side by side, with a live frame rate counter.
Ghosting Test
Spot ghosting and overshoot on dark, grey and light backgrounds, then tune overdrive.
Input Lag Test
Compare the lag of two screens with a photo timer, or film a click and flash in slow motion.
Refresh Rate Test
See the refresh rate your screen really runs at, with frame times and dropped frames.
144Hz Test
Check that your monitor really runs at 144 Hz and see 60 and 144 fps side by side.
Screen Tearing Test
Watch fast moving bars, see what tearing and stutter look like, and learn the fix for each.
Screen calculators
Aspect Ratio Calculator
Find any ratio, resize without stretching and see how 16:9, 21:9 or 9:16 fits on a screen.
PPI Calculator
Pixel density, dot pitch and the distance where pixels disappear, for any monitor, phone or TV.
What Is My Screen Resolution?
See your real screen resolution, scaling, window size and aspect ratio, and find your screen size.
Monitor Size Calculator
Width, height and area from any diagonal, with two screens drawn side by side to scale.
Finding panel faults
The dead pixel test fills your screen with solid colors so dead, stuck and hot pixels stand out, and lets you mark them for a warranty claim. If you find a stuck one, the stuck pixel fixer flashes colors over it. The monitor test runs a full set of patterns for gamma, sharpness, uniformity and viewing angles, while the backlight bleed test and burn in test look for light leaks and image retention. For color, the monitor color test shows banding, tints and clipping, and the hdr test checks whether HDR is really on. TVs and projectors have their own tv test pattern and projector test pattern sets, and the 4k test shows whether every pixel arrives.
Checking Hz and motion blur
The refresh rate test tells you the hertz your screen is really running at, and the 144hz test confirms a fast monitor is not stuck at 60. The ufo test shows motion blur at full, half and quarter frame rate, the fps test puts 30, 60 and 120 fps side by side, and the ghosting test and screen tearing test show trails and tearing during movement. To compare the delay of two screens, use the input lag test.
Solid colors for light and checks
Need a plain color? Open a white screen for light or cleaning, a black screen for OLED and backlight checks, a red screen for night vision, a green screen or blue screen for chroma key, a grey screen for uniformity, or any shade on the color screen page.
Sizes, ratios and pixel density
What is my screen resolution reads the real pixels of the screen you are on. The ppi calculator, aspect ratio calculator and monitor size calculator work out pixel density, ratios and real screen dimensions.
Display problems
The monitor flickering and second monitor not detected guides fix the most common display faults.