#66818D
Closest named color: Grey Blue (#647D8E). oklch(58.6% 0.036 226.8), rgb(102, 129, 141).
Aa
Black text reads best on this color (5.08:1).
About this color
#66818D is a medium-dark, muted teal or cyan. In OKLCH its lightness is 59%, its chroma 0.036 and its hue 227°. Its hue sits on the cool side of the wheel. The nearest named color is Grey Blue (#647D8E), ΔE 0.013 away. Black text reads best on it, at 5.08:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (59%) |
| Chroma | muted (0.036) |
| Temperature | cool |
| Nearest name | Grey Blue (#647D8E) |
| Black text | 5.08:1 |
| White text | 4.12:1 |
Values
| HEX | #66818D |
| RGB | rgb(102, 129, 141) |
| HSL | hsl(198, 16%, 48%) |
| OKLCH | oklch(58.6% 0.036 226.8) |
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 #66818D | 4.12:1 | AA large text | Lc -73.9 | Content text, not long reading |
| Black text on #66818D | 5.08:1 | AA | Lc 35.7 | Non-text elements, placeholder text |
| #66818D text on white | 4.12:1 | AA large text | Lc 68.4 | Content text, not long reading |
| #66818D text on black | 5.08:1 | AA | Lc -33.3 | 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 600.
-
Step 50
50
#F4F6F6
oklch(97.2% 0.002 197.1)
-
Step 100
100
#E7EAEC
oklch(93.5% 0.004 236.5)
-
Step 200
200
#D3DADE
oklch(88.4% 0.009 232.4)
-
Step 300
300
#B6C3C9
oklch(80.9% 0.017 227)
-
Step 400
400
#90A4AD
oklch(70.6% 0.026 226.6)
-
Step 500
500
#758E99
oklch(63.1% 0.033 226.4)
-
Step 600
600 (this color)
#66818D
oklch(58.6% 0.036 226.8)
-
Step 700
700
#4D6570
oklch(49.2% 0.034 227.7)
-
Step 800
800
#3F525B
oklch(42.6% 0.028 228.5)
-
Step 900
900
#36444B
oklch(37.7% 0.022 229.7)
-
Step 950
950
#20282C
oklch(27.1% 0.014 229.5)
#66818D 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) | #7B808E | 0.029 |
| Deuteranopia (no green cones) | #757B8D | 0.025 |
| Tritanopia (no blue cones) | #5A8585 | 0.025 |
| Achromatopsia (no color) | #7D7D7D | 0.036 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66818D
#66818D
oklch(58.6% 0.036 226.8)
- #8F766A
#8F766A
oklch(58.6% 0.036 47.1)
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 #66818D, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Grey Blue #647D8E ΔE 0.013
- Steel Grey #6F828A ΔE 0.013
- Slate Gray #708090 ΔE 0.015
- Battleship Grey #6B7C85 ΔE 0.016
- Steel #738595 ΔE 0.024
- Light Slate Gray #778899 ΔE 0.035
- Battleship Gray #6C757D ΔE 0.036
- Medium Grey #7D7F7C ΔE 0.037
Use #66818D 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.