#2D3F4B
Closest named color: Onyx (#343A40). oklch(35.7% 0.031 238), rgb(45, 63, 75).
Aa
White text reads best on this color (10.91:1).
About this color
#2D3F4B is a dark, muted blue. In OKLCH its lightness is 36%, its chroma 0.031 and its hue 238°. Its hue sits on the cool side of the wheel. The nearest named color is Onyx (#343A40), ΔE 0.022 away. White text reads best on it, at 10.91:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | muted (0.031) |
| Temperature | cool |
| Nearest name | Onyx (#343A40) |
| Black text | 1.92:1 |
| White text | 10.91:1 |
Values
| HEX | #2D3F4B |
| RGB | rgb(45, 63, 75) |
| HSL | hsl(204, 25%, 24%) |
| OKLCH | oklch(35.7% 0.031 238) |
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 #2D3F4B | 10.91:1 | AAA | Lc -99.1 | Preferred for body text |
| Black text on #2D3F4B | 1.92:1 | Fails | Lc 8.7 | Not readable |
| #2D3F4B text on white | 10.91:1 | AAA | Lc 95.2 | Preferred for body text |
| #2D3F4B text on black | 1.92:1 | Fails | Lc -7.4 | 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 900.
-
Step 50
50
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E6EBEE
oklch(93.7% 0.007 233.6)
-
Step 200
200
#D2DBE1
oklch(88.6% 0.013 236.6)
-
Step 300
300
#B3C3CE
oklch(80.8% 0.023 237.7)
-
Step 400
400
#8CA5B6
oklch(70.9% 0.037 237.8)
-
Step 500
500
#6F8EA3
oklch(63.1% 0.047 238.1)
-
Step 600
600
#56788E
oklch(55.5% 0.052 237.3)
-
Step 700
700
#466579
oklch(49.1% 0.048 237.4)
-
Step 800
800
#3A5263
oklch(42.6% 0.041 239.8)
-
Step 900
900 (this color)
#2D3F4B
oklch(35.7% 0.031 238)
-
Step 950
950
#1D282F
oklch(27% 0.02 236.4)
#2D3F4B 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) | #3A3F4C | 0.020 |
| Deuteranopia (no green cones) | #363B4B | 0.018 |
| Tritanopia (no blue cones) | #234243 | 0.024 |
| Achromatopsia (no color) | #3D3D3D | 0.031 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #2D3F4B
#2D3F4B
oklch(35.7% 0.031 238)
- #49392C
#49392C
oklch(35.8% 0.031 60.7)
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 #2D3F4B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.022
- Charcoal #264653 ΔE 0.023
- Dark Blue Grey #1F3B4D ΔE 0.024
- Charcoal Grey #3C4142 ΔE 0.029
- Dark Grey Blue #29465B ΔE 0.030
- Midnight Green #073B4C ΔE 0.040
- Gunmetal #293241 ΔE 0.044
- Prussian Blue #1D3557 ΔE 0.050
Use #2D3F4B 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.