#1C3789
Closest named color: Twilight Blue (#0A437A). oklch(37.1% 0.141 265.8), rgb(28, 55, 137).
Aa
White text reads best on this color (10.73:1).
About this color
#1C3789 is a dark, vivid blue. In OKLCH its lightness is 37%, its chroma 0.141 and its hue 266°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.044 away. White text reads best on it, at 10.73:1.
| Hue family | Blues |
| Lightness | dark (37%) |
| Chroma | vivid (0.141) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 1.95:1 |
| White text | 10.73:1 |
Values
| HEX | #1C3789 |
| RGB | rgb(28, 55, 137) |
| HSL | hsl(225, 66%, 32%) |
| OKLCH | oklch(37.1% 0.141 265.8) |
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 #1C3789 | 10.73:1 | AAA | Lc -98.3 | Preferred for body text |
| Black text on #1C3789 | 1.95:1 | Fails | Lc 9.6 | Not readable |
| #1C3789 text on white | 10.73:1 | AAA | Lc 94.3 | Preferred for body text |
| #1C3789 text on black | 1.95:1 | Fails | Lc -8.2 | 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
#F1F5FF
oklch(97% 0.014 268.5)
-
Step 100
100
#E0EAFF
oklch(93.6% 0.03 265.3)
-
Step 200
200
#C8D9FF
oklch(88.5% 0.056 266.2)
-
Step 300
300
#A4C0FF
oklch(81% 0.095 265.8)
-
Step 400
400
#739CFF
oklch(70.7% 0.152 265.7)
-
Step 500
500
#507FFF
oklch(63.1% 0.197 265.8)
-
Step 600
600
#3160FA
oklch(55.7% 0.235 265.7)
-
Step 700
700
#254DDA
oklch(49.1% 0.219 265.8)
-
Step 800
800
#1F41B0
oklch(42.8% 0.181 265.7)
-
Step 900
900 (this color)
#1C3789
oklch(37.1% 0.141 265.8)
-
Step 950
950
#112251
oklch(26.9% 0.089 265.7)
#1C3789 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) | #00438C | 0.032 |
| Deuteranopia (no green cones) | #003987 | 0.018 |
| Tritanopia (no blue cones) | #004C5A | 0.111 |
| Achromatopsia (no color) | #3E3E3E | 0.141 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #1C3789
#1C3789
oklch(37.1% 0.141 265.8)
- #523C00
#523C00
oklch(37.1% 0.076 85.3)
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 #1C3789, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.044
- Cobalt #1E488F ΔE 0.047
- Sapphire #2138AB ΔE 0.057
- Marine Blue #01386A ΔE 0.058
- Dark Slate Blue #483D8B ΔE 0.066
- Blueberry #464196 ΔE 0.069
- Royal #0C1793 ΔE 0.071
- Light Navy #155084 ΔE 0.072
Use #1C3789 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.