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Effective Tiānlán

#2bb7b1
Notes

Effective Tiānlán (#2BB7B1) is a true cyan with a cool character. It leans cool, sitting on the blue, green, and violet side of the wheel. Quiet and dependable, a fit for product UI and data visualization. Its HSL profile (177°, 62%, 44%) places it in the balanced band at a mid lightness. It works across type, buttons, and borders, saturated enough to feel deliberate but balanced enough to not fight the rest of the palette. For a confident two-color system, pair it with its complementary red. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#2bb7b1
RGB
rgb(43, 183, 177)
HSL
hsl(177, 62%, 44%)
HWB
hwb(177 17% 28%)
OKLCH
oklch(70.8% 0.113 190.5)
P3
color(display-p3 0.3557 0.7074 0.6908)
HSV
hsv(177, 77%, 72%)
LAB
lab(67.69% -36.73 -7.36)
LCH
lch(67.69% 37.46 191.34)
CMYK
cmyk(77%, 0%, 3%, 28%)

Etymology

Effective
adjective

Latin effectīvus, productive — adjectival suffix -ive. As a color modifier, effective implies a clear-and-purpose-achieving quality where the hue carries the visual register of successful-task-completion design-element. Sits at the crisp-and-functional end of the grid, parallel to practical and useful in usage.

Tiānlán
noun

Chinese for sky-blue — combining tiān (sky) and lán (blue). Used for the pale blue of clear-sky painting in Chinese landscape tradition and the tiānlán-cí (sky-blue glaze) of Song-dynasty porcelain. The color refers to a Song tiānlán glaze: a soft, slightly cool pale blue with the high gloss of fired ceramic glaze.

Closest matches

The nearest named color in three reference sources, ranked by perceptual distance (ΔE76 in CIELAB). ΔE < 1 is imperceptible to most viewers; ΔE > 10 is clearly different. When two sources point to the same hex they’re merged into one tile; click any to open that color’s page.

Variations

Click any swatch to explore

Harmonies

Accessibility

Color-vision simulation

How this color appears to viewers with the four major color-vision-deficiency types. Computed via the Machado (2009) physiologically-based model. If a tile matches the original, the color reads the same to that viewer.

#2bb7b1
Original
#acadb1
Protanopia
#989fb2
Deuteranopia
#00bcb5
Tritanopia
#999999
Achromatopsia
WCAG contrast

The color used as foreground text against pure white and pure black, with the contrast ratio and WCAG 2.1 grade. Aim for AA (4.5:1) for body text and AA Large (3:1) for 18 pt+ headlines; AAA (7:1) is the gold standard for long-form reading surfaces.

The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
Failon White
2.47:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAAon Black
8.51:1

Wide gamut

Display P3 representation

The CSS Color 4 wide-gamut form of this color. Both swatches render the same color on every display — the P3 form only diverges from sRGB when a designer pushes channels outside sRGB's reach.

sRGB hex
sRGB hex
##2BB7B1
Display P3
Display P3
color(display-p3 0.3557 0.7074 0.6908)
P3 has subtle headroomOKLCH chroma 0.113

Moderately saturated colors gain a small bump in P3 — the difference is usually visible side-by-side on wide-gamut hardware but won't change the character of the color.

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