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Straightforward Sininen

#51b5eb
Notes

Straightforward Sininen (#51B5EB) 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 (201°, 79%, 62%) places it in the highly saturated band at a mid lightness. Best used in small doses, like logos, CTAs, focus rings, or highlight text, where its saturation becomes a feature rather than noise. 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
#51b5eb
RGB
rgb(81, 181, 235)
HSL
hsl(201, 79%, 62%)
HWB
hwb(201 32% 8%)
OKLCH
oklch(73.6% 0.121 235.4)
P3
color(display-p3 0.4232 0.7010 0.9020)
HSV
hsv(201, 66%, 92%)
LAB
lab(70.03% -12.75 -35.55)
LCH
lch(70.03% 37.77 250.26)
CMYK
cmyk(66%, 23%, 0%, 8%)

Etymology

Straightforward
adjective

English compound straight + forward — sharing root with German geradeaus. As a color modifier, straightforward implies a clear-and-direct-and-unencumbered quality where the hue carries the visual register of clear-aim-and-uncomplicated character. Sits at the crisp-and-honest end of the grid, parallel to candid and direct in usage.

Sininen
noun

The Finnish word for blue — used for the Suomenlippu (Finnish flag) and the saturated blue of Finnish lake water. Sininen covers the entire blue-cyan spectrum in Finnish color vocabulary. The color refers to a Finnish lake at midsummer: a saturated, slightly cool deep blue with the optical depth of clear glacial-lake water.

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.

#51b5eb
Original
#9bb4ee
Protanopia
#86a4ea
Deuteranopia
#00c3c7
Tritanopia
#a4a4a4
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
2.29:1
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
9.16:1

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
##51B5EB
Display P3
Display P3
color(display-p3 0.4232 0.7010 0.9020)
P3 has subtle headroomOKLCH chroma 0.121

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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