#00427B
Closest named color: Twilight Blue (#0A437A). oklch(37.7% 0.113 252.1), rgb(0, 66, 123).
Aa
White text reads best on this color (10.16:1).
About this color
#00427B is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.113 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Twilight Blue (#0A437A), ΔE 0.006 away. White text reads best on it, at 10.16:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.113) |
| Temperature | cool |
| Nearest name | Twilight Blue (#0A437A) |
| Black text | 2.06:1 |
| White text | 10.16:1 |
Values
| HEX | #00427B |
| RGB | rgb(0, 66, 123) |
| HSL | hsl(208, 100%, 24%) |
| OKLCH | oklch(37.7% 0.113 252.1) |
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 #00427B | 10.16:1 | AAA | Lc -97.1 | Preferred for body text |
| Black text on #00427B | 2.06:1 | Fails | Lc 11.0 | Not readable |
| #00427B text on white | 10.16:1 | AAA | Lc 93.0 | Preferred for body text |
| #00427B text on black | 2.06:1 | Fails | Lc -9.5 | 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
#F0F6FD
oklch(97.1% 0.011 252.1)
-
Step 100
100
#DFEBFA
oklch(93.6% 0.024 254)
-
Step 200
200
#C3DCF8
oklch(88.5% 0.047 251.3)
-
Step 300
300
#99C5F6
oklch(81% 0.084 251.6)
-
Step 400
400
#5DA4F2
oklch(70.6% 0.136 252.2)
-
Step 500
500
#238BEE
oklch(63.1% 0.174 252.2)
-
Step 600
600
#0074D0
oklch(55.6% 0.166 251.9)
-
Step 700
700
#0061B0
oklch(49% 0.147 252)
-
Step 800
800
#004F92
oklch(42.6% 0.129 252.3)
-
Step 900
900 (this color)
#00427B
oklch(37.7% 0.113 252.1)
-
Step 950
950
#062748
oklch(27% 0.072 252.2)
#00427B 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) | #23477D | 0.029 |
| Deuteranopia (no green cones) | #063D7A | 0.014 |
| Tritanopia (no blue cones) | #005058 | 0.083 |
| Achromatopsia (no color) | #414141 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #00427B
#00427B
oklch(37.7% 0.113 252.1)
- #5C3900
#5C3900
oklch(37.7% 0.081 71.3)
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 #00427B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Twilight Blue #0A437A ΔE 0.006
- Marine Blue #01386A ΔE 0.040
- Cobalt #1E488F ΔE 0.043
- Light Navy #155084 ΔE 0.046
- Deep Sea Blue #015482 ΔE 0.055
- Dark Grey Blue #29465B ΔE 0.065
- Dusk Blue #26538D ΔE 0.065
- Prussian Blue #1D3557 ΔE 0.068
Use #00427B 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.