#066CB0
Closest named color: Mid Blue (#276AB3). oklch(51.7% 0.134 247.1), rgb(6, 108, 176).
Aa
White text reads best on this color (5.55:1).
About this color
#066CB0 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 52%, its chroma 0.134 and its hue 247°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.015 away. White text reads best on it, at 5.55:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.134) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.77:1 |
| White text | 5.55:1 |
Values
| HEX | #066CB0 |
| RGB | rgb(6, 108, 176) |
| HSL | hsl(204, 93%, 36%) |
| OKLCH | oklch(51.7% 0.134 247.1) |
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 #066CB0 | 5.55:1 | AA | Lc -82.5 | Fine for body text |
| Black text on #066CB0 | 3.77:1 | AA large text | Lc 26.9 | Dividers and decoration only |
| #066CB0 text on white | 5.55:1 | AA | Lc 77.2 | Fine for body text |
| #066CB0 text on black | 3.77:1 | AA large text | Lc -24.6 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E0EBF6
oklch(93.5% 0.019 248)
-
Step 200
200
#C7DCF0
oklch(88.5% 0.036 246.9)
-
Step 300
300
#9FC5E9
oklch(80.8% 0.065 247.2)
-
Step 400
400
#69A6DE
oklch(70.6% 0.104 247.5)
-
Step 500
500
#3B8FD5
oklch(63.1% 0.133 247.2)
-
Step 600
600
#0878C2
oklch(55.7% 0.144 246.9)
-
Step 700
700 (this color)
#066CB0
oklch(51.7% 0.134 247.1)
-
Step 800
800
#035288
oklch(42.7% 0.111 247.3)
-
Step 900
900
#12446D
oklch(37.6% 0.087 247.8)
-
Step 950
950
#0D2840
oklch(27% 0.056 248.3)
#066CB0 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) | #4A70B3 | 0.048 |
| Deuteranopia (no green cones) | #3162AF | 0.031 |
| Tritanopia (no blue cones) | #007D85 | 0.096 |
| Achromatopsia (no color) | #686868 | 0.134 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #066CB0
#066CB0
oklch(51.7% 0.134 247.1)
- #935900
#935900
oklch(51.8% 0.114 67.1)
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 #066CB0, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.015
- French Blue #436BAD ΔE 0.037
- Ocean Blue #03719C ΔE 0.038
- Flat Blue #3C73A8 ΔE 0.041
- Nice Blue #107AB0 ΔE 0.042
- Peacock Blue #016795 ΔE 0.044
- Muted Blue #3B719F ΔE 0.044
- Windows Blue #3778BF ΔE 0.050
Use #066CB0 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.