#42737B
Closest named color: Deep Aqua (#08787F). oklch(52.4% 0.054 209), rgb(66, 115, 123).
Aa
White text reads best on this color (5.28:1).
About this color
#42737B is a medium-dark, muted teal or cyan. In OKLCH its lightness is 52%, its chroma 0.054 and its hue 209°. Its hue sits on the cool side of the wheel. The nearest named color is Deep Aqua (#08787F), ΔE 0.034 away. White text reads best on it, at 5.28:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (52%) |
| Chroma | muted (0.054) |
| Temperature | cool |
| Nearest name | Deep Aqua (#08787F) |
| Black text | 3.96:1 |
| White text | 5.28:1 |
Values
| HEX | #42737B |
| RGB | rgb(66, 115, 123) |
| HSL | hsl(188, 30%, 37%) |
| OKLCH | oklch(52.4% 0.054 209) |
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 #42737B | 5.28:1 | AA | Lc -81.5 | Fine for body text |
| Black text on #42737B | 3.96:1 | AA large text | Lc 27.9 | Dividers and decoration only |
| #42737B text on white | 5.28:1 | AA | Lc 76.2 | Fine for body text |
| #42737B text on black | 3.96:1 | AA large text | Lc -25.5 | 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 600.
-
Step 50
50
#F3F6F7
oklch(97.1% 0.003 219.5)
-
Step 100
100
#E5EBEC
oklch(93.6% 0.007 208.8)
-
Step 200
200
#CFDCDE
oklch(88.5% 0.014 207.9)
-
Step 300
300
#AFC5C9
oklch(80.8% 0.025 209.8)
-
Step 400
400
#85A8AE
oklch(70.8% 0.039 209.1)
-
Step 500
500
#65929A
oklch(63% 0.05 209.8)
-
Step 600
600 (this color)
#42737B
oklch(52.4% 0.054 209)
-
Step 700
700
#3C6970
oklch(49.1% 0.051 208.4)
-
Step 800
800
#32565B
oklch(42.8% 0.042 207)
-
Step 900
900
#2C474B
oklch(37.8% 0.033 207.6)
-
Step 950
950
#1A292C
oklch(26.9% 0.021 211.4)
#42737B 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) | #6B707C | 0.052 |
| Deuteranopia (no green cones) | #62697B | 0.047 |
| Tritanopia (no blue cones) | #277775 | 0.028 |
| Achromatopsia (no color) | #6C6C6C | 0.055 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42737B
#42737B
oklch(52.4% 0.054 209)
- #875E58
#875E58
oklch(52.4% 0.055 28.4)
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 #42737B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Deep Aqua #08787F ΔE 0.034
- Metallic Blue #4F738E ΔE 0.036
- Bluegreen #017A79 ΔE 0.040
- Deep Turquoise #017374 ΔE 0.040
- Slate #516572 ΔE 0.042
- Dark Aquamarine #017371 ΔE 0.043
- Ocean #017B92 ΔE 0.045
- Teal #008080 ΔE 0.046
Use #42737B 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.