Gamma Calibration Test.
Squint until the striped and solid halves blend — that's your monitor's actual gamma, checked against the 2.2 standard.
Gamma fusion
Each bar is 1-pixel lines (left) beside the solid grey that matches them at gamma 2.2 (right). Step back a metre or squint: if the two halves melt into one flat tone, your gamma is on target. If the solid half stands out lighter or darker, your gamma is off. View at 100% browser zoom — the lines rely on exact pixels.
Which gamma is your screen hitting?
A 50% line dither with the solid grey for four gammas beside it. The patch that blends into the stripes is your display's gamma — aim for 2.2.
50% reference dither
The values sit close together on purpose — gamma is a subtle, whole-screen quality. If the 2.2 patch is clearly the match, you're calibrated; if a neighbour matches better, nudge your monitor's gamma preset toward 2.2 and re-check.
Shadow & highlight detail
Eight steps across the darkest, middle and brightest tones. Every step should be distinct from its neighbours. If the darkest steps merge into black, shadows are crushed; if the brightest merge into white, highlights are clipped.
Shadow detail
2 – 20%Midtone
20 – 77%Highlight detail
82 – 100%What your results mean
Compare the striped and solid halves in the fusion and curve-compare patterns, and the ladders' steps, to read your display's actual gamma against the 2.2 target.
| What you see | What it means | What to do |
|---|---|---|
| The striped half blends into the solid grey half when you squint or step back | Your gamma is close to 2.2, the standard for general use — correct | Nothing to do. |
| The solid grey half looks lighter than the striped half | Gamma is too low — mid-tones look washed out and flat | Raise gamma toward 2.2 in the monitor's picture menu, then re-check. |
| The solid grey half looks darker than the striped half | Gamma is too high — shadows lose detail (crushed blacks) | Lower gamma toward 2.2 in the monitor's picture menu. |
| In curve compare, the 1.8, 2.0, or 2.4 patch blends into the stripes better than the 2.2 patch | Your display is actually running that gamma, not 2.2 | Nudge the monitor's gamma preset toward the value that matched, then re-test. |
| The darkest 2-3 steps of the shadow-detail ladder look identical to each other | Black crush — shadow detail is being lost | Lower contrast or gamma and turn off dynamic-contrast / vivid modes; also see the black level test. |
| The brightest 2-3 steps of the highlight-detail ladder look blown out to white | Highlights are clipping — detail near white is lost | Lower brightness or contrast slightly; if it persists at neutral settings, that's a hardware limit. |
Frequently asked questions
What is monitor gamma?
Gamma is the curve that maps the digital signal (0–255) to the light your screen actually emits. It is not linear: it devotes more steps to the darks, because your eyes are more sensitive to changes there. The standard for computer displays is a gamma of about 2.2 (the sRGB standard). If your gamma is off, shadows look crushed or washed out and midtones sit too dark or too bright.
How does the gamma fusion test work?
The striped half of each bar is 1-pixel black and white lines. Physically those average to a fixed amount of light — 50% for equal lines — regardless of your display's gamma. The solid half is the single grey value that equals that light level only if your gamma is 2.2. So when you step back or squint and the two halves blend into one flat tone, your gamma is 2.2. If the solid looks lighter or darker than the stripes, your gamma is lower or higher. View at 100% zoom for it to work.
What gamma should my monitor be set to?
For general use in a normally-lit room, 2.2 is the standard target and what sRGB assumes. Dark-room video mastering often uses 2.4, and legacy Macs used 1.8 (long since changed to 2.2). Unless you have a specific reason, set 2.2 — most monitors have a gamma option in their menu, and OS calibration tools can nudge it. Use the curve-compare pattern here to see which value your screen is actually hitting.
Why do my shadows look crushed or washed out?
Crushed shadows (dark detail disappearing into black) usually mean your gamma is too high or the black level / contrast is set too aggressively. Washed-out shadows (greyish blacks, flat darks) mean gamma too low or brightness too high. Run the shadow-detail ladder: if the darkest two or three steps look identical, detail is being lost. Adjust gamma toward 2.2 and re-check.
Does gamma calibration replace a colorimeter?
No — this is a visual check, and your eyes plus room lighting introduce error. It is excellent for spotting a clearly wrong gamma and for setting a monitor's gamma preset by eye, but a hardware colorimeter with calibration software measures the curve precisely and builds an ICC profile. Use this test to get close and to verify; use a colorimeter when you need certified accuracy.