colors
Back to gallery

Straightforward Diatom

#055a1f
Notes

Straightforward Diatom (#055A1F) 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 (138°, 89%, 19%) places it in the highly saturated band at a dark 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 magenta. For something softer, pull in its analogous neighbors on either side of the wheel.

HEX
#055a1f
RGB
rgb(5, 90, 31)
HSL
hsl(138, 89%, 19%)
HWB
hwb(138 2% 65%)
OKLCH
oklch(40.8% 0.118 147.2)
P3
color(display-p3 0.1491 0.3473 0.1513)
HSV
hsv(138, 94%, 35%)
LAB
lab(32.79% -36.90 27.11)
LCH
lch(32.79% 45.79 143.70)
CMYK
cmyk(94%, 0%, 66%, 65%)

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.

Diatom
noun

Single-celled algae with intricate silica cell walls — among the most numerous photosynthetic organisms on Earth, producing roughly a quarter of global oxygen. The color refers to a diatom-bloom-tinted lake at midday: a soft, slightly cool deep blue-green with the optical complexity of suspended single-celled 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.

#055a1f
Original
#5b5119
Protanopia
#524b24
Deuteranopia
#00584d
Tritanopia
#444444
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
8.44:1
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
2.49:1

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
##055A1F
Display P3
Display P3
color(display-p3 0.1491 0.3473 0.1513)
P3 has subtle headroomOKLCH chroma 0.118

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