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Punchy Aries Cerulean

#217bbf
Notes

Punchy Aries Cerulean (#217BBF) is a true azure with a vibrant character. It holds its own as a focal accent, carrying visual weight without tipping into neon territory. Its HSL profile (206°, 71%, 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 orange. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#217bbf
RGB
rgb(33, 123, 191)
HSL
hsl(206, 71%, 44%)
HWB
hwb(206 13% 25%)
OKLCH
oklch(56.6% 0.133 246.6)
P3
color(display-p3 0.2418 0.4754 0.7280)
HSV
hsv(206, 83%, 75%)
LAB
lab(49.80% -1.28 -42.79)
LCH
lch(49.80% 42.81 268.28)
CMYK
cmyk(83%, 36%, 0%, 25%)

Etymology

Punchy
adjective

A modern adjectival form of punch, to strike sharply. Used as a color word since the early twentieth century for hues that read as highly contrasting and visually loud. Punchy red, punchy yellow: the implication is full saturation combined with optical impact. Sits across the bold and bright buckets, near vivid and striking.

Aries
modifier

Latin aries, ram-of-the-fleece. As a color modifier, aries implies a ram-and-fire-sign-and-Mars-ruled-cardinal-fire quality, the visual register of Babylonian-ram-and-Greek-Aries hand-ram-and-fire-sign-and-Mars-ruled-cardinal-fire Babylonian-ram-and-Greek-Aries-and-Golden-Fleece aries-and-ram-and-fire-sign surfaces under Babylonian-ram-and-Greek-Aries-and-Golden-Fleece spring-equinox-and-March-and-April fire-sign-light. Sits at the modifier-and-zodiac end of the grid, parallel to taurus and gemini in usage.

Cerulean
noun

From the Latin caeruleum, originally referring to dark blue paint pigment of the Roman world, then via French céruléen into English. As a modern art-supply name, cerulean blue is the cobalt-tin oxide pigment introduced in 1805. The color refers to a clean, slightly green-shifted blue with the matte finish of mineral pigment in linseed oil: lighter than cobalt, deeper than aqua, with the painter's weight of a word for sky.

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.

#217bbf
Original
#5b7ec2
Protanopia
#4470be
Deuteranopia
#008b94
Tritanopia
#6d6d6d
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).
AAon White
4.52:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
AAon Black
4.65:1

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
##217BBF
Display P3
Display P3
color(display-p3 0.2418 0.4754 0.7280)
P3 has subtle headroomOKLCH chroma 0.133

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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