#42509C
Closest named color: Twilight (#4E518B). oklch(46% 0.124 272.8), rgb(66, 80, 156).
Aa
White text reads best on this color (7.34:1).
About this color
#42509C is a medium-dark, moderately saturated blue. In OKLCH its lightness is 46%, its chroma 0.124 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight (#4E518B), ΔE 0.033 away. White text reads best on it, at 7.34:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | moderately saturated (0.124) |
| Temperature | cool |
| Nearest name | Twilight (#4E518B) |
| Black text | 2.85:1 |
| White text | 7.34:1 |
Values
| HEX | #42509C |
| RGB | rgb(66, 80, 156) |
| HSL | hsl(231, 41%, 44%) |
| OKLCH | oklch(46% 0.124 272.8) |
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 #42509C | 7.34:1 | AAA | Lc -90.2 | Preferred for body text |
| Black text on #42509C | 2.85:1 | Fails | Lc 18.7 | Dividers and decoration only |
| #42509C text on white | 7.34:1 | AAA | Lc 85.3 | Fine for body text |
| #42509C text on black | 2.85:1 | Fails | Lc -16.7 | Dividers and decoration only |
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 700.
-
Step 50
50
#F3F5FB
oklch(97% 0.008 271.3)
-
Step 100
100
#E6E9F6
oklch(93.6% 0.018 275.6)
-
Step 200
200
#D1D8F0
oklch(88.4% 0.034 272.8)
-
Step 300
300
#B3BFE8
oklch(80.9% 0.06 272.2)
-
Step 400
400
#8C9DDD
oklch(70.7% 0.096 272.3)
-
Step 500
500
#7183D3
oklch(63.1% 0.122 272.8)
-
Step 600
600
#5A6BC0
oklch(55.5% 0.133 272.8)
-
Step 700
700 (this color)
#42509C
oklch(46% 0.124 272.8)
-
Step 800
800
#3D4986
oklch(42.6% 0.102 273)
-
Step 900
900
#343E6C
oklch(37.8% 0.08 272.8)
-
Step 950
950
#1E243F
oklch(26.9% 0.051 273)
#42509C 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) | #2B5A9F | 0.034 |
| Deuteranopia (no green cones) | #1E529A | 0.037 |
| Tritanopia (no blue cones) | #09616E | 0.110 |
| Achromatopsia (no color) | #565656 | 0.124 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42509C
#42509C
oklch(46% 0.124 272.8)
- #6A5600
#6A5600
oklch(46% 0.094 93.2)
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 #42509C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight #4E518B ΔE 0.033
- Denim Blue #3B5B92 ΔE 0.038
- Blueberry #464196 ΔE 0.039
- Dusk Blue #26538D ΔE 0.042
- Dusky Blue #475F94 ΔE 0.048
- Dusk #4E5481 ΔE 0.051
- Light Navy Blue #2E5A88 ΔE 0.052
- Cobalt #1E488F ΔE 0.053
Use #42509C 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.