#42507E
Closest named color: Dusk (#4E5481). oklch(44.1% 0.078 270.1), rgb(66, 80, 126).
Aa
White text reads best on this color (7.83:1).
About this color
#42507E is a dark, moderately saturated blue. In OKLCH its lightness is 44%, its chroma 0.078 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Dusk (#4E5481), ΔE 0.022 away. White text reads best on it, at 7.83:1.
| Hue family | Blues |
| Lightness | dark (44%) |
| Chroma | moderately saturated (0.078) |
| Temperature | cool |
| Nearest name | Dusk (#4E5481) |
| Black text | 2.68:1 |
| White text | 7.83:1 |
Values
| HEX | #42507E |
| RGB | rgb(66, 80, 126) |
| HSL | hsl(226, 31%, 38%) |
| OKLCH | oklch(44.1% 0.078 270.1) |
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 #42507E | 7.83:1 | AAA | Lc -91.8 | Preferred for body text |
| Black text on #42507E | 2.68:1 | Fails | Lc 16.9 | Dividers and decoration only |
| #42507E text on white | 7.83:1 | AAA | Lc 87.1 | Fine for body text |
| #42507E text on black | 2.68:1 | Fails | Lc -15.0 | 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
#F4F5FA
oklch(97.1% 0.007 277.2)
-
Step 100
100
#E6EAF3
oklch(93.7% 0.013 266.7)
-
Step 200
200
#D2D9EB
oklch(88.5% 0.026 268.8)
-
Step 300
300
#B5C0DF
oklch(80.9% 0.045 269.9)
-
Step 400
400
#8F9FCF
oklch(70.8% 0.073 270.2)
-
Step 500
500
#7386C2
oklch(62.9% 0.093 270.1)
-
Step 600
600
#5C6FAF
oklch(55.5% 0.102 270.3)
-
Step 700
700
#4C5D96
oklch(49.1% 0.094 270.1)
-
Step 800
800 (this color)
#42507E
oklch(44.1% 0.078 270.1)
-
Step 900
900
#354062
oklch(37.8% 0.06 269.7)
-
Step 950
950
#1F2539
oklch(26.9% 0.038 270.9)
#42507E 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) | #3F5580 | 0.014 |
| Deuteranopia (no green cones) | #394F7D | 0.013 |
| Tritanopia (no blue cones) | #2C5A61 | 0.070 |
| Achromatopsia (no color) | #525252 | 0.078 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #42507E
#42507E
oklch(44.1% 0.078 270.1)
- #635017
#635017
oklch(43.9% 0.078 89.9)
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 #42507E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dusk #4E5481 ΔE 0.022
- Twilight #4E518B ΔE 0.028
- Light Navy Blue #2E5A88 ΔE 0.035
- YInMn Blue #415A77 ΔE 0.035
- Dusk Blue #26538D ΔE 0.037
- Dusty Grape #545775 ΔE 0.040
- Denim Blue #3B5B92 ΔE 0.040
- Light Navy #155084 ΔE 0.045
Use #42507E 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.