Calibrate your monitor's brightness and contrast settings. Check black level detail, white clipping, and contrast ratio using standard reference patterns used by display professionals.
Incorrect brightness and contrast settings cause you to lose detail in shadows and highlights. Too-high brightness clips dark tones into solid black. Too-high contrast crushes bright highlights to pure white. These reference patterns — used by broadcast engineers and display professionals — let you quickly set accurate brightness and contrast without expensive calibration hardware.
Eight patches from pure black (0) to level 64. Correct brightness setting: level 0 is pure black, level 5 is just barely visible. If levels 5–16 all look identical, brightness is too low.
Eight patches from level 210 to pure white (255). Correct contrast: level 255 looks white, level 250 is distinctly lighter than 245. If top levels appear identical, contrast is too high.
Alternating 4×4 grid of pure black and white. Measures real-world contrast ratio including backlight bleed. The ratio of white patch luminance to black patch luminance is the ANSI contrast ratio.
1-pixel alternating black/white grid. Should appear as uniform gray from normal viewing distance. Tests sharpness, sub-pixel rendering, and whether artificial sharpening is active.
Broadcast standard black-level calibration. Adjust brightness until the sub-black bars (0, 0a) disappear into the background while the +1 bar remains just visible.
More free tools to check your setup.
Test your monitor for dead pixels, stuck pixels, and screen uniformity with our professional color testing tool.
Test your monitor for color banding and bit depth issues using smooth gradient and stepped color patterns.
Check your monitor for backlight bleeding, IPS glow, and uneven brightness with full-screen solid color tests.
Test HDR display performance: peak brightness, shadow detail, contrast ratio, and color volume using Canvas-rendered test patterns.
Check monitor shadow detail with near-black patches from value 1 to 30 and a PLUGE calibration pattern. Normal and inverted modes.
Guides on monitor calibration, color accuracy, and display specifications.
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Found a bright dot on screen? Use our free Screen Test to locate stuck pixels, try safe fixes, and know when to claim warranty.
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A black dot on white is usually a dead pixel. A bright colored dot on black is usually a stuck pixel. Here is how to check before you try a fix or ask for a return.
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