#1B4366
Closest named color: Dark Grey Blue (#29465B). oklch(37.2% 0.075 247.8), rgb(27, 67, 102).
Aa
White text reads best on this color (10.28:1).
About this color
#1B4366 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.075 and its hue 248°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.027 away. White text reads best on it, at 10.28:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.075) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.04:1 |
| White text | 10.28:1 |
Values
| HEX | #1B4366 |
| RGB | rgb(27, 67, 102) |
| HSL | hsl(208, 58%, 25%) |
| OKLCH | oklch(37.2% 0.075 247.8) |
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 #1B4366 | 10.28:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #1B4366 | 2.04:1 | Fails | Lc 10.3 | Not readable |
| #1B4366 text on white | 10.28:1 | AAA | Lc 93.7 | Preferred for body text |
| #1B4366 text on black | 2.04:1 | Fails | Lc -8.9 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF5
oklch(93.6% 0.017 250.8)
-
Step 200
200
#C9DCED
oklch(88.6% 0.031 245.1)
-
Step 300
300
#A4C5E4
oklch(81% 0.057 246.9)
-
Step 400
400
#72A6D6
oklch(70.7% 0.09 247.2)
-
Step 500
500
#4B8FCC
oklch(63.2% 0.115 247.8)
-
Step 600
600
#2A78B8
oklch(55.7% 0.124 247.4)
-
Step 700
700
#1C649F
oklch(49% 0.117 248.2)
-
Step 800
800
#1A5281
oklch(42.7% 0.097 248)
-
Step 900
900 (this color)
#1B4366
oklch(37.2% 0.075 247.8)
-
Step 950
950
#12283D
oklch(27% 0.048 249)
#1B4366 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) | #334468 | 0.028 |
| Deuteranopia (no green cones) | #293D65 | 0.022 |
| Tritanopia (no blue cones) | #004B50 | 0.055 |
| Achromatopsia (no color) | #414141 | 0.075 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B4366
#1B4366
oklch(37.2% 0.075 247.8)
- #5A380A
#5A380A
oklch(37.3% 0.075 68.5)
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 #1B4366, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.027
- Twilight Blue #0A437A ΔE 0.035
- Charcoal #264653 ΔE 0.038
- Marine Blue #01386A ΔE 0.043
- Dark Blue Grey #1F3B4D ΔE 0.045
- Prussian Blue #1D3557 ΔE 0.047
- Midnight Green #073B4C ΔE 0.053
- Light Navy #155084 ΔE 0.058
Use #1B4366 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.