#373A4E
Closest named color: Onyx (#343A40). oklch(35.4% 0.035 277.8), rgb(55, 58, 78).
Aa
White text reads best on this color (11.18:1).
About this color
#373A4E is a dark, muted blue. In OKLCH its lightness is 35%, its chroma 0.035 and its hue 278°. Its hue sits on the cool side of the wheel. The nearest named color is Onyx (#343A40), ΔE 0.026 away. White text reads best on it, at 11.18:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | muted (0.035) |
| Temperature | cool |
| Nearest name | Onyx (#343A40) |
| Black text | 1.87:1 |
| White text | 11.18:1 |
Values
| HEX | #373A4E |
| RGB | rgb(55, 58, 78) |
| HSL | hsl(232, 17%, 26%) |
| OKLCH | oklch(35.4% 0.035 277.8) |
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 #373A4E | 11.18:1 | AAA | Lc -99.6 | Preferred for body text |
| Black text on #373A4E | 1.87:1 | Fails | Lc 8.0 | Not readable |
| #373A4E text on white | 11.18:1 | AAA | Lc 95.8 | Preferred for body text |
| #373A4E text on black | 1.87:1 | Fails | Lc 0.0 | 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
#F5F5F8
oklch(97.1% 0.004 286.3)
-
Step 100
100
#E8E9EF
oklch(93.5% 0.008 278.6)
-
Step 200
200
#D6D8E3
oklch(88.4% 0.015 277.8)
-
Step 300
300
#BCBFD2
oklch(80.8% 0.027 278.6)
-
Step 400
400
#9A9FBB
oklch(70.8% 0.041 277.3)
-
Step 500
500
#8187AA
oklch(63.1% 0.053 277.2)
-
Step 600
600
#6B7096
oklch(55.6% 0.059 278.5)
-
Step 700
700
#595E80
oklch(49.1% 0.055 277.7)
-
Step 800
800
#494D68
oklch(42.8% 0.045 277.8)
-
Step 900
900 (this color)
#373A4E
oklch(35.4% 0.035 277.8)
-
Step 950
950
#242631
oklch(27.1% 0.021 276.9)
#373A4E 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) | #343C4F | 0.007 |
| Deuteranopia (no green cones) | #333A4D | 0.007 |
| Tritanopia (no blue cones) | #313E41 | 0.032 |
| Achromatopsia (no color) | #3B3B3B | 0.035 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #373A4E
#373A4E
oklch(35.4% 0.035 277.8)
- #403C26
#403C26
oklch(35.4% 0.036 99.1)
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 #373A4E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.026
- Dark Blue Grey #1F3B4D ΔE 0.033
- Charcoal Grey #3C4142 ΔE 0.037
- Gunmetal #293241 ΔE 0.040
- Dark Grey Blue #29465B ΔE 0.040
- Charcoal #264653 ΔE 0.041
- Prussian Blue #1D3557 ΔE 0.046
- Space Cadet #2B2D42 ΔE 0.049
Use #373A4E 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.