#066BB5
Closest named color: Mid Blue (#276AB3). oklch(51.8% 0.141 249.2), rgb(6, 107, 181).
Aa
White text reads best on this color (5.55:1).
About this color
#066BB5 is a medium-dark, vivid blue. In OKLCH its lightness is 52%, its chroma 0.141 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.013 away. White text reads best on it, at 5.55:1.
| Hue family | Blues |
| Lightness | medium-dark (52%) |
| Chroma | vivid (0.141) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.77:1 |
| White text | 5.55:1 |
Values
| HEX | #066BB5 |
| RGB | rgb(6, 107, 181) |
| HSL | hsl(205, 94%, 37%) |
| OKLCH | oklch(51.8% 0.141 249.2) |
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 #066BB5 | 5.55:1 | AA | Lc -82.5 | Fine for body text |
| Black text on #066BB5 | 3.77:1 | AA large text | Lc 26.9 | Dividers and decoration only |
| #066BB5 text on white | 5.55:1 | AA | Lc 77.1 | Fine for body text |
| #066BB5 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
#E0EBF7
oklch(93.5% 0.02 250.4)
-
Step 200
200
#C7DCF2
oklch(88.6% 0.038 249.5)
-
Step 300
300
#9FC5EC
oklch(80.9% 0.069 249.4)
-
Step 400
400
#68A6E2
oklch(70.8% 0.109 248.9)
-
Step 500
500
#3A8EDA
oklch(63.1% 0.14 249.2)
-
Step 600
600
#0776C7
oklch(55.5% 0.152 249.3)
-
Step 700
700 (this color)
#066BB5
oklch(51.8% 0.141 249.2)
-
Step 800
800
#03518B
oklch(42.7% 0.116 249.2)
-
Step 900
900
#11446F
oklch(37.7% 0.09 248.7)
-
Step 950
950
#0C2841
oklch(27% 0.058 248.6)
#066BB5 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) | #4570B8 | 0.044 |
| Deuteranopia (no green cones) | #2962B4 | 0.026 |
| Tritanopia (no blue cones) | #007D87 | 0.102 |
| Achromatopsia (no color) | #686868 | 0.141 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #066BB5
#066BB5
oklch(51.8% 0.141 249.2)
- #915A00
#915A00
oklch(51.7% 0.113 69.1)
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 #066BB5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.013
- French Blue #436BAD ΔE 0.038
- Nice Blue #107AB0 ΔE 0.046
- Flat Blue #3C73A8 ΔE 0.047
- Ocean Blue #03719C ΔE 0.047
- Windows Blue #3778BF ΔE 0.050
- Muted Blue #3B719F ΔE 0.051
- Peacock Blue #016795 ΔE 0.051
Use #066BB5 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.