#37555B
Closest named color: Dark Slate Gray (#2F4F4F). oklch(42.8% 0.037 211.5), rgb(55, 85, 91).
Aa
White text reads best on this color (8.03:1).
About this color
#37555B is a dark, muted teal or cyan. In OKLCH its lightness is 43%, its chroma 0.037 and its hue 212°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Gray (#2F4F4F), ΔE 0.027 away. White text reads best on it, at 8.03:1.
| Hue family | Teals and cyans |
| Lightness | dark (43%) |
| Chroma | muted (0.037) |
| Temperature | cool |
| Nearest name | Dark Slate Gray (#2F4F4F) |
| Black text | 2.61:1 |
| White text | 8.03:1 |
Values
| HEX | #37555B |
| RGB | rgb(55, 85, 91) |
| HSL | hsl(190, 25%, 29%) |
| OKLCH | oklch(42.8% 0.037 211.5) |
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 #37555B | 8.03:1 | AAA | Lc -92.5 | Preferred for body text |
| Black text on #37555B | 2.61:1 | Fails | Lc 16.2 | Dividers and decoration only |
| #37555B text on white | 8.03:1 | AAA | Lc 87.8 | Fine for body text |
| #37555B text on black | 2.61:1 | Fails | Lc -14.3 | Not readable |
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
#F3F6F6
oklch(97.1% 0.003 197.1)
-
Step 100
100
#E5EBEC
oklch(93.6% 0.007 208.8)
-
Step 200
200
#D1DBDE
oklch(88.5% 0.012 217.6)
-
Step 300
300
#B2C5C9
oklch(81% 0.022 211.8)
-
Step 400
400
#89A7AD
oklch(70.8% 0.034 211.1)
-
Step 500
500
#6B9199
oklch(63.1% 0.044 212.1)
-
Step 600
600
#527B83
oklch(55.6% 0.047 211.1)
-
Step 700
700
#42686F
oklch(49.2% 0.044 210.4)
-
Step 800
800 (this color)
#37555B
oklch(42.8% 0.037 211.5)
-
Step 900
900
#30464A
oklch(37.8% 0.028 210)
-
Step 950
950
#1C292C
oklch(27% 0.019 213.5)
#37555B 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) | #50535B | 0.035 |
| Deuteranopia (no green cones) | #4A4E5B | 0.032 |
| Tritanopia (no blue cones) | #295857 | 0.020 |
| Achromatopsia (no color) | #505050 | 0.037 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37555B
#37555B
oklch(42.8% 0.037 211.5)
- #624843
#624843
oklch(42.8% 0.037 31)
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 #37555B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Gray #2F4F4F ΔE 0.027
- Deep Teal #00555A ΔE 0.039
- Petrol #005F6A ΔE 0.043
- YInMn Blue #415A77 ΔE 0.049
- Dark Green Blue #1F6357 ΔE 0.051
- Dark Grey Blue #29465B ΔE 0.054
- Charcoal #264653 ΔE 0.055
- Dark Blue Green #005249 ΔE 0.055
Use #37555B 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.