#37457B
Closest named color: Cobalt (#1E488F). oklch(40.6% 0.092 270.9), rgb(55, 69, 123).
Aa
White text reads best on this color (9.13:1).
About this color
#37457B is a dark, moderately saturated blue. In OKLCH its lightness is 41%, its chroma 0.092 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.041 away. White text reads best on it, at 9.13:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | moderately saturated (0.092) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.29:1 |
| White text | 9.13:1 |
Values
| HEX | #37457B |
| RGB | rgb(55, 69, 123) |
| HSL | hsl(228, 38%, 35%) |
| OKLCH | oklch(40.6% 0.092 270.9) |
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 #37457B | 9.13:1 | AAA | Lc -95.3 | Preferred for body text |
| Black text on #37457B | 2.29:1 | Fails | Lc 13.1 | Not readable |
| #37457B text on white | 9.13:1 | AAA | Lc 90.9 | Preferred for body text |
| #37457B text on black | 2.29:1 | Fails | Lc -11.4 | 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
#F3F5FA
oklch(97% 0.007 268.5)
-
Step 100
100
#E6EAF5
oklch(93.7% 0.015 270)
-
Step 200
200
#D1D9EE
oklch(88.6% 0.03 269.1)
-
Step 300
300
#B3BFE4
oklch(80.8% 0.054 271)
-
Step 400
400
#8C9ED7
oklch(70.7% 0.086 270.6)
-
Step 500
500
#7185CC
oklch(63.1% 0.11 271)
-
Step 600
600
#596EB9
oklch(55.6% 0.119 270.4)
-
Step 700
700
#495BA0
oklch(49% 0.113 270.8)
-
Step 800
800 (this color)
#37457B
oklch(40.6% 0.092 270.9)
-
Step 900
900
#333F68
oklch(37.7% 0.072 270.3)
-
Step 950
950
#1E253D
oklch(27% 0.046 270.7)
#37457B 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) | #2F4B7D | 0.019 |
| Deuteranopia (no green cones) | #27457A | 0.020 |
| Tritanopia (no blue cones) | #16515A | 0.083 |
| Achromatopsia (no color) | #484848 | 0.092 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37457B
#37457B
oklch(40.6% 0.092 270.9)
- #5A4700
#5A4700
oklch(40.6% 0.083 91.2)
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 #37457B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.041
- Light Navy #155084 ΔE 0.041
- Twilight Blue #0A437A ΔE 0.043
- Dark Slate Blue #483D8B ΔE 0.044
- Dusk Blue #26538D ΔE 0.046
- Blueberry #464196 ΔE 0.053
- Deep Sea Blue #015482 ΔE 0.053
- Twilight #4E518B ΔE 0.056
Use #37457B 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.