#1B488E
Closest named color: Cobalt (#1E488F). oklch(41.2% 0.126 259.2), rgb(27, 72, 142).
Aa
White text reads best on this color (8.88:1).
About this color
#1B488E is a dark, moderately saturated blue. In OKLCH its lightness is 41%, its chroma 0.126 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.003 away. White text reads best on it, at 8.88:1.
| Hue family | Blues |
| Lightness | dark (41%) |
| Chroma | moderately saturated (0.126) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.36:1 |
| White text | 8.88:1 |
Values
| HEX | #1B488E |
| RGB | rgb(27, 72, 142) |
| HSL | hsl(217, 68%, 33%) |
| OKLCH | oklch(41.2% 0.126 259.2) |
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 #1B488E | 8.88:1 | AAA | Lc -94.4 | Preferred for body text |
| Black text on #1B488E | 2.36:1 | Fails | Lc 14.1 | Not readable |
| #1B488E text on white | 8.88:1 | AAA | Lc 89.9 | Fine for body text |
| #1B488E text on black | 2.36:1 | Fails | Lc -12.3 | 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 800.
-
Step 50
50
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EBF9
oklch(93.7% 0.021 259.2)
-
Step 200
200
#C9DAF5
oklch(88.4% 0.042 259.6)
-
Step 300
300
#A4C2F1
oklch(80.8% 0.074 259.3)
-
Step 400
400
#73A1EA
oklch(70.6% 0.119 259.3)
-
Step 500
500
#4E88E3
oklch(63.1% 0.15 259.1)
-
Step 600
600
#3170D1
oklch(55.7% 0.163 259)
-
Step 700
700
#245DB5
oklch(49.1% 0.152 259.1)
-
Step 800
800 (this color)
#1B488E
oklch(41.2% 0.126 259.2)
-
Step 900
900
#1F4075
oklch(37.7% 0.099 259.5)
-
Step 950
950
#132644
oklch(27% 0.061 259.2)
#1B488E 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) | #204F91 | 0.021 |
| Deuteranopia (no green cones) | #00458D | 0.018 |
| Tritanopia (no blue cones) | #005964 | 0.098 |
| Achromatopsia (no color) | #4A4A4A | 0.126 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B488E
#1B488E
oklch(41.2% 0.126 259.2)
- #634400
#634400
oklch(41.1% 0.085 79.1)
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 #1B488E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.003
- Light Navy #155084 ΔE 0.031
- Dusk Blue #26538D ΔE 0.035
- Twilight Blue #0A437A ΔE 0.038
- Deep Sea Blue #015482 ΔE 0.044
- Blueberry #464196 ΔE 0.054
- Dark Slate Blue #483D8B ΔE 0.058
- Light Navy Blue #2E5A88 ΔE 0.061
Use #1B488E 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.