Adjust. Observe. Check.
One instruction at a time, on the pattern. Use your monitor controls.
Visual detail check. Does not measure color accuracy. Adjust in your monitor menu.
Free tests, report and explanations
1. Create a stable reference
The goal is to preserve detail and make comparisons repeatable. Without a colorimeter we cannot certify D65, luminance, gamut or ΔE accuracy, or create a measured ICC profile. Seeing more steps does not guarantee accurate colors.
- Let the monitor warm up for about 30 minutes. Use stable ambient lighting without reflections; keep your head position and viewing distance fixed.
- Record the current preset and settings before changing anything. For SDR web content, start with the manufacturer’s sRGB or standard mode. Do not copy another monitor’s settings.
- Test in SDR: temporarily disable HDR, night light and automatic contrast/brightness. Preserve your current color profile and record changes so you can restore them.
- Use native resolution and 100% browser zoom. Graphics output and display RGB ranges must match. These patterns use 0–255; they are not limited-range 16–235 video patterns.
- Adjust using the monitor controls. This page only displays patterns; it does not change hardware. Rest your gaze on neutral gray and avoid staring at saturated colors for long periods.
Brightness often controls panel light output; black level and contrast have different roles. If settings seem interchangeable, consult your model’s manual.
My monitor has game mode, HDR Effect or DCB
Record and temporarily disable enhancements such as simulated HDR Effect, DCB/natural skin, game color, dynamic contrast and shadow enhancement. Use the manufacturer’s neutral setting: the lowest number is not always neutral. After adjusting the baseline, restore only what you want and repeat the tests; keep separate setups for fidelity and games.
Respect control increments: if a setting changes in steps of 10, compare adjacent positions and choose the one that preserves detail without washing out the image. This page cannot provide finer precision than the menu offers.
2. Preserve shadow detail
Observe steps from 0 to 30. Level 0 should stay black and higher steps should become progressively visible. Do not force levels 1 or 2 to appear by washing out black. Set comfortable brightness first; if many levels are crushed, check RGB range and black level before gamma.
3. Find channel clipping
Compare steps from 225 to 255 in gray and each RGB channel. If the last blocks merge into one band, slightly reduce contrast or that channel’s gain in the monitor menu and repeat. Preserve separation without tinting gray. The limit depends on preset and contrast.
A value such as R76/G86/B72 is a menu setting, not a universal tolerance or proof of correct white. Record your own values in the final step. Use the blind check to see whether you can still discriminate without knowing where to look.
4. Compare midtones and gamma
The solid center should approach the average brightness of the black/white checkerboard when viewed far enough away for dots to blend. Select 2.2 as a common SDR approximation; adjust monitor gamma, not the target, for the comparison. This target is a power curve, not the exact sRGB transfer function.
Presets named Gamma 1, 2 and 3 do not necessarily represent curve exponents. Compare presets while keeping the target fixed. Only interpret with true pixel mapping, without scaling, moiré or artificial sharpening. This page compensates for browser-reported pixel density but cannot verify physical mapping. If lines and dots disagree, discard the estimate. Then inspect the neutral gradient: bands can originate in the display, profile, browser or processing.
5. Separate position from perception
Display uniform gray. Inspect center and corners with your head fixed, then move to face each region directly. Changes with viewing angle suggest angle dependence. A patch that stays in the same region suggests non-uniformity. Global RGB controls do not fix local differences.
For a global tint, start with the manufacturer’s sRGB or standard color-temperature preset. Make only small RGB changes, check all three gray levels and revisit highlights for clipping. Your eyes adapt to screen white: apparent neutrality does not verify D65.
6. Verify without knowing the answer
In each trial, one of four patches has a higher digital value. Choose it even if uncertain. Position is randomized each time and answers are revealed only after 16 trials to reduce learning during the run. Do not adjust the monitor mid-run.
Repeat the same condition before and after a small adjustment. Correct answers show discrimination in this test; they do not measure color accuracy or isolate display, vision and environment. Avoid repeating until you “pass”: confirm with another run and rest between runs.
7. Record a reproducible setup
Record menu values, their scale and preset. They are not applied to patterns or sent to a server. Download the report before closing: nothing is stored in the browser.
Recheck shadows, highlights and gray after any RGB change. Compare again the next day under the same conditions. For color-critical accuracy, validate with an instrument and suitable profile.
Method and references
Patterns are generated locally in browser sRGB. The check uses four alternatives, fixed values per run and independent random positions; chance per trial is 25%. No light measurement is made. Gamma patterns use 50% black/white pixels and a center of 255 × 0.5^(1/gamma).
References: EIZO Monitor Test (preparation, uniformity and pixel mapping); EIZO Understanding Monitor Gamma (tonal response). Tests and guidance on this page were implemented by Zeluvo.