#155D51
Closest named color: Dark Green Blue (#1F6357). oklch(43.2% 0.071 178.9), rgb(21, 93, 81).
Aa
White text reads best on this color (7.73:1).
About this color
#155D51 is a dark, moderately saturated teal or cyan. In OKLCH its lightness is 43%, its chroma 0.071 and its hue 179°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Green Blue (#1F6357), ΔE 0.022 away. White text reads best on it, at 7.73:1.
| Hue family | Teals and cyans |
| Lightness | dark (43%) |
| Chroma | moderately saturated (0.071) |
| Temperature | cool |
| Nearest name | Dark Green Blue (#1F6357) |
| Black text | 2.71:1 |
| White text | 7.73:1 |
Values
| HEX | #155D51 |
| RGB | rgb(21, 93, 81) |
| HSL | hsl(170, 63%, 22%) |
| OKLCH | oklch(43.2% 0.071 178.9) |
Contrast
WCAG 2 contrast ratios are the conformance target: AA needs 4.5:1 for body text and 3:1 for large text, AAA needs 7:1. APCA Lc values are supplementary guidance from the WCAG 3 drafts.
| Pair | WCAG 2 | Result | APCA | APCA guidance |
|---|---|---|---|---|
| White text on #155D51 | 7.73:1 | AAA | Lc -91.3 | Preferred for body text |
| Black text on #155D51 | 2.71:1 | Fails | Lc 17.5 | Dividers and decoration only |
| #155D51 text on white | 7.73:1 | AAA | Lc 86.5 | Fine for body text |
| #155D51 text on black | 2.71:1 | Fails | Lc -15.5 | Dividers and decoration only |
Tints and shades
A 50–950 scale built in OKLCH: the hue is held, lightness follows a Tailwind v4-like curve, and every step is kept inside the sRGB gamut. This color sits at step 800.
-
Step 50
50
#F2F7F5
oklch(97.2% 0.006 170.4)
-
Step 100
100
#E2EDEA
oklch(93.7% 0.012 178)
-
Step 200
200
#CADED9
oklch(88.4% 0.022 179.1)
-
Step 300
300
#A5CAC1
oklch(81% 0.041 178.8)
-
Step 400
400
#71AFA1
oklch(70.8% 0.068 178.4)
-
Step 500
500
#479A8A
oklch(63% 0.085 179)
-
Step 600
600
#208574
oklch(55.6% 0.093 178.6)
-
Step 700
700
#0F7062
oklch(49% 0.085 179.7)
-
Step 800
800 (this color)
#155D51
oklch(43.2% 0.071 178.9)
-
Step 900
900
#194B42
oklch(37.6% 0.056 179.2)
-
Step 950
950
#112C27
oklch(27% 0.035 179.9)
#155D51 with color blindness
Simulated with the Machado et al. (2009) model. ΔE is how far the color moves: below about 0.02 you would not notice a change.
| Vision | Seen as | Shift (ΔE) |
|---|---|---|
| Protanopia (no red cones) | #595751 | 0.076 |
| Deuteranopia (no green cones) | #4F5052 | 0.071 |
| Tritanopia (no blue cones) | #005F59 | 0.013 |
| Achromatopsia (no color) | #535353 | 0.072 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #155D51
#155D51
oklch(43.2% 0.071 178.9)
- #703F4F
#703F4F
oklch(43.2% 0.071 359.5)
Analogous
Neighbouring hues, 30° either side.
Split complementary
The two hues beside the complement (150° and 210°).
Triadic
Three hues spaced 120° apart.
Palettes with this color
Curated palettes that contain a color within ΔE 0.04 (OKLab) of #155D51, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Green Blue #1F6357 ΔE 0.022
- Deep Teal #00555A ΔE 0.036
- Dark Blue Green #005249 ΔE 0.039
- Petrol #005F6A ΔE 0.040
- Spruce #0A5F38 ΔE 0.043
- Pine #2B5D34 ΔE 0.044
- Dark Slate Gray #2F4F4F ΔE 0.047
- Dark Aqua #05696B ΔE 0.048
Use #155D51 in your product
Turn it into light and dark UI roles checked for contrast, then export to Tailwind v4, shadcn/ui, CSS or design tokens.