#373D59
Closest named color: Dark Grey Blue (#29465B). oklch(36.7% 0.049 274.5), rgb(55, 61, 89).
Aa
White text reads best on this color (10.63:1).
About this color
#373D59 is a dark, muted blue. In OKLCH its lightness is 37%, its chroma 0.049 and its hue 274°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.032 away. White text reads best on it, at 10.63:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | muted (0.049) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 1.97:1 |
| White text | 10.63:1 |
Values
| HEX | #373D59 |
| RGB | rgb(55, 61, 89) |
| HSL | hsl(229, 24%, 28%) |
| OKLCH | oklch(36.7% 0.049 274.5) |
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 #373D59 | 10.63:1 | AAA | Lc -98.6 | Preferred for body text |
| Black text on #373D59 | 1.97:1 | Fails | Lc 9.3 | Not readable |
| #373D59 text on white | 10.63:1 | AAA | Lc 94.6 | Preferred for body text |
| #373D59 text on black | 1.97:1 | Fails | Lc -8.0 | 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 900.
-
Step 50
50
#F4F5F9
oklch(97.1% 0.005 275)
-
Step 100
100
#E7E9F1
oklch(93.5% 0.011 274.9)
-
Step 200
200
#D5D8E7
oklch(88.4% 0.021 276.9)
-
Step 300
300
#B9BFD9
oklch(80.8% 0.037 275.2)
-
Step 400
400
#959EC6
oklch(70.6% 0.059 274.9)
-
Step 500
500
#7B86B7
oklch(63% 0.075 274.3)
-
Step 600
600
#656FA3
oklch(55.5% 0.082 275.1)
-
Step 700
700
#545D8C
oklch(49.1% 0.076 275)
-
Step 800
800
#444C72
oklch(42.6% 0.064 274.3)
-
Step 900
900 (this color)
#373D59
oklch(36.7% 0.049 274.5)
-
Step 950
950
#222536
oklch(27% 0.032 276.3)
#373D59 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) | #34405A | 0.010 |
| Deuteranopia (no green cones) | #323D58 | 0.008 |
| Tritanopia (no blue cones) | #2D4247 | 0.043 |
| Achromatopsia (no color) | #3E3E3E | 0.049 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373D59
#373D59
oklch(36.7% 0.049 274.5)
- #473F1F
#473F1F
oklch(36.8% 0.05 95.7)
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 #373D59, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.032
- Charcoal #264653 ΔE 0.039
- Dark Blue Grey #1F3B4D ΔE 0.041
- Onyx #343A40 ΔE 0.044
- Charcoal Grey #3C4142 ΔE 0.047
- Prussian Blue #1D3557 ΔE 0.047
- Gunmetal #293241 ΔE 0.056
- Midnight Green #073B4C ΔE 0.059
Use #373D59 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.