#1B4075
Closest named color: Twilight Blue (#0A437A). oklch(37.5% 0.1 257.8), rgb(27, 64, 117).
Aa
White text reads best on this color (10.31:1).
About this color
#1B4075 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.100 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.014 away. White text reads best on it, at 10.31:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | moderately saturated (0.100) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.03:1 |
| White text | 10.31:1 |
Values
| HEX | #1B4075 |
| RGB | rgb(27, 64, 117) |
| HSL | hsl(215, 63%, 28%) |
| OKLCH | oklch(37.5% 0.1 257.8) |
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 #1B4075 | 10.31:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #1B4075 | 2.03:1 | Fails | Lc 10.3 | Not readable |
| #1B4075 text on white | 10.31:1 | AAA | Lc 93.6 | Preferred for body text |
| #1B4075 text on black | 2.03:1 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E1EBF9
oklch(93.7% 0.022 256.7)
-
Step 200
200
#C8DBF5
oklch(88.5% 0.041 256.2)
-
Step 300
300
#A3C3F2
oklch(81% 0.075 257.9)
-
Step 400
400
#70A2EB
oklch(70.7% 0.12 257.8)
-
Step 500
500
#4989E5
oklch(63.2% 0.154 257.7)
-
Step 600
600
#2A70D3
oklch(55.6% 0.168 258)
-
Step 700
700
#1C5DB7
oklch(49.1% 0.157 258)
-
Step 800
800
#1A4D94
oklch(42.8% 0.129 257.8)
-
Step 900
900 (this color)
#1B4075
oklch(37.5% 0.1 257.8)
-
Step 950
950
#112645
oklch(27% 0.064 258.1)
#1B4075 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) | #264577 | 0.020 |
| Deuteranopia (no green cones) | #153D74 | 0.011 |
| Tritanopia (no blue cones) | #004C54 | 0.078 |
| Achromatopsia (no color) | #404040 | 0.100 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B4075
#1B4075
oklch(37.5% 0.1 257.8)
- #573B00
#573B00
oklch(37.5% 0.078 78.7)
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 #1B4075, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.014
- Marine Blue #01386A ΔE 0.037
- Cobalt #1E488F ΔE 0.048
- Light Navy #155084 ΔE 0.050
- Dark Grey Blue #29465B ΔE 0.054
- Prussian Blue #1D3557 ΔE 0.057
- Deep Sea Blue #015482 ΔE 0.059
- Dusk Blue #26538D ΔE 0.067
Use #1B4075 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.