#37457F
Closest named color: Cobalt (#1E488F). oklch(40.9% 0.099 271.3), rgb(55, 69, 127).
Aa
White text reads best on this color (9.05:1).
About this color
#37457F is a dark, moderately saturated blue. In OKLCH its lightness is 41%, its chroma 0.099 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.036 away. White text reads best on it, at 9.05:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | moderately saturated (0.099) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.32:1 |
| White text | 9.05:1 |
Values
| HEX | #37457F |
| RGB | rgb(55, 69, 127) |
| HSL | hsl(228, 40%, 36%) |
| OKLCH | oklch(40.9% 0.099 271.3) |
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 #37457F | 9.05:1 | AAA | Lc -95.0 | Preferred for body text |
| Black text on #37457F | 2.32:1 | Fails | Lc 13.3 | Not readable |
| #37457F text on white | 9.05:1 | AAA | Lc 90.6 | Preferred for body text |
| #37457F text on black | 2.32:1 | Fails | Lc -11.7 | 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
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E6EAF5
oklch(93.7% 0.015 270)
-
Step 200
200
#D1D8EF
oklch(88.4% 0.033 272.2)
-
Step 300
300
#B3BFE7
oklch(80.9% 0.058 272)
-
Step 400
400
#8B9DDB
oklch(70.6% 0.093 271.4)
-
Step 500
500
#7084D1
oklch(63.1% 0.118 271.6)
-
Step 600
600
#596DBE
oklch(55.7% 0.128 271.3)
-
Step 700
700
#495AA4
oklch(49.1% 0.12 271.6)
-
Step 800
800 (this color)
#37457F
oklch(40.9% 0.099 271.3)
-
Step 900
900
#333E6A
oklch(37.6% 0.077 271.7)
-
Step 950
950
#1E253E
oklch(27.1% 0.048 271.1)
#37457F 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) | #2C4C81 | 0.022 |
| Deuteranopia (no green cones) | #23467E | 0.023 |
| Tritanopia (no blue cones) | #11525C | 0.088 |
| Achromatopsia (no color) | #494949 | 0.099 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #37457F
#37457F
oklch(40.9% 0.099 271.3)
- #5B4800
#5B4800
oklch(41% 0.084 91.5)
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 #37457F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.036
- Dark Slate Blue #483D8B ΔE 0.039
- Light Navy #155084 ΔE 0.041
- Dusk Blue #26538D ΔE 0.044
- Twilight Blue #0A437A ΔE 0.044
- Blueberry #464196 ΔE 0.046
- Twilight #4E518B ΔE 0.053
- Deep Sea Blue #015482 ΔE 0.053
Use #37457F 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.