#1B3673
Closest named color: Marine Blue (#01386A). oklch(35% 0.11 263.7), rgb(27, 54, 115).
Aa
White text reads best on this color (11.52:1).
About this color
#1B3673 is a dark, moderately saturated blue. In OKLCH its lightness is 35%, its chroma 0.110 and its hue 264°. Its hue sits on the cool side of the wheel. The nearest named color is Marine Blue (#01386A), ΔE 0.025 away. White text reads best on it, at 11.52:1.
| Hue family | Blues |
| Lightness | dark (35%) |
| Chroma | moderately saturated (0.110) |
| Temperature | cool |
| Nearest name | Marine Blue (#01386A) |
| Black text | 1.82:1 |
| White text | 11.52:1 |
Values
| HEX | #1B3673 |
| RGB | rgb(27, 54, 115) |
| HSL | hsl(222, 62%, 28%) |
| OKLCH | oklch(35% 0.11 263.7) |
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 #1B3673 | 11.52:1 | AAA | Lc -99.9 | Preferred for body text |
| Black text on #1B3673 | 1.82:1 | Fails | Lc 7.7 | Not readable |
| #1B3673 text on white | 11.52:1 | AAA | Lc 96.2 | Preferred for body text |
| #1B3673 text on black | 1.82:1 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFA
oklch(93.6% 0.023 264.5)
-
Step 200
200
#CADAF8
oklch(88.6% 0.045 263.1)
-
Step 300
300
#A5C1F7
oklch(80.9% 0.083 263.3)
-
Step 400
400
#759EF3
oklch(70.6% 0.133 263.8)
-
Step 500
500
#5384EF
oklch(63.2% 0.169 263.7)
-
Step 600
600
#386ADD
oklch(55.5% 0.184 263.7)
-
Step 700
700
#2B58C0
oklch(49.1% 0.171 263.7)
-
Step 800
800
#24489B
oklch(42.6% 0.142 263.8)
-
Step 900
900 (this color)
#1B3673
oklch(35% 0.11 263.7)
-
Step 950
950
#142548
oklch(27.1% 0.069 263.1)
#1B3673 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) | #103D75 | 0.020 |
| Deuteranopia (no green cones) | #003572 | 0.020 |
| Tritanopia (no blue cones) | #00454F | 0.088 |
| Achromatopsia (no color) | #393939 | 0.110 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B3673
#1B3673
oklch(35% 0.11 263.7)
- #4C3600
#4C3600
oklch(34.9% 0.072 83.2)
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 #1B3673, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Marine Blue #01386A ΔE 0.025
- Twilight Blue #0A437A ΔE 0.038
- Marine #042E60 ΔE 0.046
- Prussian Blue #1D3557 ΔE 0.049
- Cobalt #1E488F ΔE 0.067
- Dark Blue Grey #1F3B4D ΔE 0.072
- Midnight Blue #191970 ΔE 0.073
- Dark Grey Blue #29465B ΔE 0.074
Use #1B3673 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.