#37447A
Closest named color: Cobalt (#1E488F). oklch(40.3% 0.092 271.5), rgb(55, 68, 122).
Aa
White text reads best on this color (9.24:1).
About this color
#37447A is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.092 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.042 away. White text reads best on it, at 9.24:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.092) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.27:1 |
| White text | 9.24:1 |
Values
| HEX | #37447A |
| RGB | rgb(55, 68, 122) |
| HSL | hsl(228, 38%, 35%) |
| OKLCH | oklch(40.3% 0.092 271.5) |
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 #37447A | 9.24:1 | AAA | Lc -95.5 | Preferred for body text |
| Black text on #37447A | 2.27:1 | Fails | Lc 12.8 | Not readable |
| #37447A text on white | 9.24:1 | AAA | Lc 91.2 | Preferred for body text |
| #37447A text on black | 2.27:1 | Fails | Lc -11.2 | 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E6E9F5
oklch(93.5% 0.016 274.8)
-
Step 200
200
#D2D8EE
oklch(88.4% 0.031 273.6)
-
Step 300
300
#B4BFE4
oklch(80.8% 0.054 272.1)
-
Step 400
400
#8D9ED7
oklch(70.8% 0.086 271.3)
-
Step 500
500
#7285CC
oklch(63.2% 0.109 271.6)
-
Step 600
600
#5A6DB9
oklch(55.5% 0.12 271.4)
-
Step 700
700
#4A5B9F
oklch(49% 0.111 271.2)
-
Step 800
800 (this color)
#37447A
oklch(40.3% 0.092 271.5)
-
Step 900
900
#343F68
oklch(37.8% 0.072 271.3)
-
Step 950
950
#1E253D
oklch(27% 0.046 270.7)
#37447A 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) | #2E4A7C | 0.019 |
| Deuteranopia (no green cones) | #264579 | 0.021 |
| Tritanopia (no blue cones) | #175059 | 0.083 |
| Achromatopsia (no color) | #474747 | 0.092 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37447A
#37447A
oklch(40.3% 0.092 271.5)
- #594600
#594600
oklch(40.3% 0.082 91)
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 #37447A, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.042
- Twilight Blue #0A437A ΔE 0.043
- Light Navy #155084 ΔE 0.044
- Dark Slate Blue #483D8B ΔE 0.044
- Dusk Blue #26538D ΔE 0.049
- Blueberry #464196 ΔE 0.053
- Deep Sea Blue #015482 ΔE 0.055
- Twilight #4E518B ΔE 0.058
Use #37447A 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.