#373D52
Closest named color: Onyx (#343A40). oklch(36.4% 0.037 272.1), rgb(55, 61, 82).
Aa
White text reads best on this color (10.75:1).
About this color
#373D52 is a dark, muted blue. In OKLCH its lightness is 36%, its chroma 0.037 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Onyx (#343A40), ΔE 0.032 away. White text reads best on it, at 10.75:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | muted (0.037) |
| Temperature | cool |
| Nearest name | Onyx (#343A40) |
| Black text | 1.95:1 |
| White text | 10.75:1 |
Values
| HEX | #373D52 |
| RGB | rgb(55, 61, 82) |
| HSL | hsl(227, 20%, 27%) |
| OKLCH | oklch(36.4% 0.037 272.1) |
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 #373D52 | 10.75:1 | AAA | Lc -98.8 | Preferred for body text |
| Black text on #373D52 | 1.95:1 | Fails | Lc 9.0 | Not readable |
| #373D52 text on white | 10.75:1 | AAA | Lc 94.9 | Preferred for body text |
| #373D52 text on black | 1.95:1 | Fails | Lc -7.7 | 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 900.
-
Step 50
50
#F4F5F8
oklch(97% 0.004 271.4)
-
Step 100
100
#E8EAEF
oklch(93.7% 0.007 268.5)
-
Step 200
200
#D5D9E4
oklch(88.5% 0.016 270)
-
Step 300
300
#BAC0D3
oklch(80.9% 0.028 271.8)
-
Step 400
400
#979FBD
oklch(70.6% 0.045 273.5)
-
Step 500
500
#7D88AD
oklch(63.1% 0.057 271.8)
-
Step 600
600
#667198
oklch(55.5% 0.062 272.1)
-
Step 700
700
#555F82
oklch(49.1% 0.058 271.8)
-
Step 800
800
#464E6A
oklch(42.9% 0.048 271.9)
-
Step 900
900 (this color)
#373D52
oklch(36.4% 0.037 272.1)
-
Step 950
950
#222632
oklch(27% 0.023 270.4)
#373D52 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) | #373F53 | 0.006 |
| Deuteranopia (no green cones) | #343D51 | 0.005 |
| Tritanopia (no blue cones) | #304144 | 0.034 |
| Achromatopsia (no color) | #3E3E3E | 0.037 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373D52
#373D52
oklch(36.4% 0.037 272.1)
- #453E27
#453E27
oklch(36.5% 0.038 93.1)
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 #373D52, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.032
- Dark Grey Blue #29465B ΔE 0.032
- Charcoal #264653 ΔE 0.034
- Charcoal Grey #3C4142 ΔE 0.035
- Dark Blue Grey #1F3B4D ΔE 0.036
- Prussian Blue #1D3557 ΔE 0.049
- Gunmetal #293241 ΔE 0.049
- Midnight Green #073B4C ΔE 0.055
Use #373D52 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.