#66748C
Closest named color: Grey Blue (#647D8E). oklch(55.6% 0.041 261.2), rgb(102, 116, 140).
Aa
White text reads best on this color (4.72:1).
About this color
#66748C is a medium-dark, muted blue. In OKLCH its lightness is 56%, its chroma 0.041 and its hue 261°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.026 away. White text reads best on it, at 4.72:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | muted (0.041) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 4.44:1 |
| White text | 4.72:1 |
Values
| HEX | #66748C |
| RGB | rgb(102, 116, 140) |
| HSL | hsl(218, 16%, 47%) |
| OKLCH | oklch(55.6% 0.041 261.2) |
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 #66748C | 4.72:1 | AA | Lc -78.3 | Fine for body text |
| Black text on #66748C | 4.44:1 | AA large text | Lc 31.3 | Non-text elements, placeholder text |
| #66748C text on white | 4.72:1 | AA | Lc 72.8 | Content text, not long reading |
| #66748C text on black | 4.44:1 | AA large text | Lc -28.9 | 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 600.
-
Step 50
50
#F4F5F7
oklch(97% 0.003 264.5)
-
Step 100
100
#E8EAED
oklch(93.6% 0.005 258.3)
-
Step 200
200
#D5D9E0
oklch(88.4% 0.011 261.8)
-
Step 300
300
#BAC1CD
oklch(80.9% 0.019 261.3)
-
Step 400
400
#96A1B4
oklch(70.6% 0.03 261.4)
-
Step 500
500
#7D8AA1
oklch(63.1% 0.038 261.9)
-
Step 600
600 (this color)
#66748C
oklch(55.6% 0.041 261.2)
-
Step 700
700
#556177
oklch(49.1% 0.038 262.5)
-
Step 800
800
#454F61
oklch(42.6% 0.033 262.1)
-
Step 900
900
#3A424F
oklch(37.7% 0.025 260.1)
-
Step 950
950
#22272E
oklch(27.1% 0.015 256.8)
#66748C 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) | #6C758D | 0.009 |
| Deuteranopia (no green cones) | #68728B | 0.006 |
| Tritanopia (no blue cones) | #5C797C | 0.036 |
| Achromatopsia (no color) | #737373 | 0.041 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66748C
#66748C
oklch(55.6% 0.041 261.2)
- #807158
#807158
oklch(55.6% 0.041 80.3)
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 #66748C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.026
- Battleship Gray #6C757D ΔE 0.026
- Metallic Blue #4F738E ΔE 0.030
- Battleship Grey #6B7C85 ΔE 0.030
- Stormy Blue #507B9C ΔE 0.035
- Slate Gray #708090 ΔE 0.038
- Dull Blue #49759C ΔE 0.041
- Cerulean #457B9D ΔE 0.044
Use #66748C 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.