colors
Back to gallery

Straightforward Spirulina

#155e29
Notes

Straightforward Spirulina (#155E29) is a deep green with a jewel character. It carries the deep, saturated richness of a gemstone. Authoritative and slightly formal, it works well for type and heavy UI elements. Its HSL profile (136°, 63%, 23%) places it in the balanced band at a dark lightness. It works well as a headline, icon, or deep background in an otherwise light layout, pairing cleanly with cream, bone, and warm neutrals. For a confident two-color system, pair it with its complementary magenta. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#155e29
RGB
rgb(21, 94, 41)
HSL
hsl(136, 63%, 23%)
HWB
hwb(136 8% 63%)
OKLCH
oklch(42.5% 0.110 148.2)
P3
color(display-p3 0.1757 0.3631 0.1843)
HSV
hsv(136, 78%, 37%)
LAB
lab(34.65% -34.64 24.00)
LCH
lch(34.65% 42.14 145.28)
CMYK
cmyk(78%, 0%, 56%, 63%)

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.

Spirulina
noun

Arthrospira platensis, the cyanobacterium harvested from alkaline lakes since the time of the Aztecs and now sold globally as a nutritional supplement and natural food coloring. The color refers to fresh-dried spirulina powder in a small bowl: a saturated, slightly cool deep blue-green with the matte finish of dehydrated cyanobacterial cells. Cooler than algae.

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.

#155e29
Original
#5f5524
Protanopia
#564f2d
Deuteranopia
#005c52
Tritanopia
#4b4b4b
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).
AAAon White
7.88:1
The quick brown foxSample body text at normal size. The wcag minimum for body contrast is 4.5:1 (AA) or 7:1 (AAA).
Failon Black
2.66:1

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
##155E29
Display P3
Display P3
color(display-p3 0.1757 0.3631 0.1843)
P3 has subtle headroomOKLCH chroma 0.110

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.

Related Colors

Canvas