#66859B
Closest named color: Steel (#738595). oklch(60.1% 0.049 239.5), rgb(102, 133, 155).
Aa
Black text reads best on this color (5.39:1).
About this color
#66859B is a medium-dark, muted blue. In OKLCH its lightness is 60%, its chroma 0.049 and its hue 240°. Its hue sits on the cool side of the wheel. The nearest named color is Steel (#738595), ΔE 0.018 away. Black text reads best on it, at 5.39:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | muted (0.049) |
| Temperature | cool |
| Nearest name | Steel (#738595) |
| Black text | 5.39:1 |
| White text | 3.89:1 |
Values
| HEX | #66859B |
| RGB | rgb(102, 133, 155) |
| HSL | hsl(205, 21%, 50%) |
| OKLCH | oklch(60.1% 0.049 239.5) |
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 #66859B | 3.89:1 | AA large text | Lc -71.9 | Content text, not long reading |
| Black text on #66859B | 5.39:1 | AA | Lc 37.7 | Non-text elements, placeholder text |
| #66859B text on white | 3.89:1 | AA large text | Lc 66.4 | Content text, not long reading |
| #66859B text on black | 5.39:1 | AA | Lc -35.3 | Non-text elements, placeholder text |
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 500.
-
Step 50
50
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E6EBEE
oklch(93.7% 0.007 233.6)
-
Step 200
200
#D2DAE1
oklch(88.4% 0.013 244.3)
-
Step 300
300
#B3C3CF
oklch(80.9% 0.024 240.2)
-
Step 400
400
#8CA4B6
oklch(70.6% 0.038 240.5)
-
Step 500
500 (this color)
#66859B
oklch(60.1% 0.049 239.5)
-
Step 600
600
#56788F
oklch(55.6% 0.053 238.5)
-
Step 700
700
#46657A
oklch(49.1% 0.05 238.7)
-
Step 800
800
#3A5263
oklch(42.6% 0.041 239.8)
-
Step 900
900
#324451
oklch(37.7% 0.032 240.1)
-
Step 950
950
#1D282F
oklch(27% 0.02 236.4)
#66859B 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) | #7C849C | 0.029 |
| Deuteranopia (no green cones) | #747F9B | 0.024 |
| Tritanopia (no blue cones) | #558B8C | 0.039 |
| Achromatopsia (no color) | #818181 | 0.049 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66859B
#66859B
oklch(60.1% 0.049 239.5)
- #977A64
#977A64
oklch(60.1% 0.048 58.9)
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 #66859B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel #738595 ΔE 0.018
- Slate Gray #708090 ΔE 0.021
- Light Slate Gray #778899 ΔE 0.025
- Steel Grey #6F828A ΔE 0.026
- Grey Blue #647D8E ΔE 0.027
- Dusty Blue #5A86AD ΔE 0.029
- Blue Grey #758DA3 ΔE 0.032
- Off Blue #5684AE ΔE 0.034
Use #66859B 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.