#1B4683
Closest named color: Cobalt (#1E488F). oklch(39.9% 0.113 257.8), rgb(27, 70, 131).
Aa
White text reads best on this color (9.33:1).
About this color
#1B4683 is a dark, moderately saturated blue. In OKLCH its lightness is 40%, its chroma 0.113 and its hue 258°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.021 away. White text reads best on it, at 9.33:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.25:1 |
| White text | 9.33:1 |
Values
| HEX | #1B4683 |
| RGB | rgb(27, 70, 131) |
| HSL | hsl(215, 66%, 31%) |
| OKLCH | oklch(39.9% 0.113 257.8) |
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 #1B4683 | 9.33:1 | AAA | Lc -95.5 | Preferred for body text |
| Black text on #1B4683 | 2.25:1 | Fails | Lc 12.8 | Not readable |
| #1B4683 text on white | 9.33:1 | AAA | Lc 91.2 | Preferred for body text |
| #1B4683 text on black | 2.25:1 | Fails | Lc -11.2 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E0EBFB
oklch(93.7% 0.025 257.6)
-
Step 200
200
#C6DBF9
oklch(88.5% 0.047 257.3)
-
Step 300
300
#9FC3F8
oklch(81% 0.085 257.9)
-
Step 400
400
#69A1F4
oklch(70.6% 0.136 258.1)
-
Step 500
500
#3E87F0
oklch(63.1% 0.174 257.9)
-
Step 600
600
#186EDE
oklch(55.5% 0.188 257.8)
-
Step 700
700
#075BC1
oklch(49% 0.175 257.8)
-
Step 800
800
#0D4B9C
oklch(42.6% 0.145 257.8)
-
Step 900
900 (this color)
#1B4683
oklch(39.9% 0.113 257.8)
-
Step 950
950
#0D2649
oklch(27.1% 0.072 257.4)
#1B4683 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) | #264C85 | 0.022 |
| Deuteranopia (no green cones) | #104282 | 0.015 |
| Tritanopia (no blue cones) | #00545E | 0.086 |
| Achromatopsia (no color) | #474747 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1B4683
#1B4683
oklch(39.9% 0.113 257.8)
- #604100
#604100
oklch(40% 0.083 78.1)
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 #1B4683, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.021
- Twilight Blue #0A437A ΔE 0.021
- Light Navy #155084 ΔE 0.029
- Deep Sea Blue #015482 ΔE 0.042
- Dusk Blue #26538D ΔE 0.042
- Dark Slate Blue #483D8B ΔE 0.061
- Marine Blue #01386A ΔE 0.062
- Blueberry #464196 ΔE 0.063
Use #1B4683 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.