#66818B
Closest named color: Steel Grey (#6F828A). oklch(58.6% 0.035 222.5), rgb(102, 129, 139).
Aa
Black text reads best on this color (5.07:1).
About this color
#66818B is a medium-dark, muted teal or cyan. In OKLCH its lightness is 59%, its chroma 0.035 and its hue 222°. Its hue sits on the cool side of the wheel. The nearest named color is Steel Grey (#6F828A), ΔE 0.013 away. Black text reads best on it, at 5.07:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (59%) |
| Chroma | muted (0.035) |
| Temperature | cool |
| Nearest name | Steel Grey (#6F828A) |
| Black text | 5.07:1 |
| White text | 4.13:1 |
Values
| HEX | #66818B |
| RGB | rgb(102, 129, 139) |
| HSL | hsl(196, 15%, 47%) |
| OKLCH | oklch(58.6% 0.035 222.5) |
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 #66818B | 4.13:1 | AA large text | Lc -73.9 | Content text, not long reading |
| Black text on #66818B | 5.07:1 | AA | Lc 35.6 | Non-text elements, placeholder text |
| #66818B text on white | 4.13:1 | AA large text | Lc 68.4 | Content text, not long reading |
| #66818B text on black | 5.07:1 | AA | Lc -33.2 | 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
#D3DADD
oklch(88.4% 0.009 225.1)
-
Step 300
300
#B6C3C8
oklch(80.9% 0.016 222.7)
-
Step 400
400
#91A4AC
oklch(70.6% 0.024 225)
-
Step 500
500
#758E98
oklch(63.1% 0.032 224.1)
-
Step 600
600 (this color)
#66818B
oklch(58.6% 0.035 222.5)
-
Step 700
700
#4D656E
oklch(49.1% 0.032 222.9)
-
Step 800
800
#3F525A
oklch(42.6% 0.027 225.5)
-
Step 900
900
#36444A
oklch(37.7% 0.021 225.8)
-
Step 950
950
#20282B
oklch(27% 0.013 222.5)
#66818B 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) | #7B7F8C | 0.029 |
| Deuteranopia (no green cones) | #757B8B | 0.025 |
| Tritanopia (no blue cones) | #5B8484 | 0.021 |
| Achromatopsia (no color) | #7D7D7D | 0.035 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #66818B
#66818B
oklch(58.6% 0.035 222.5)
- #8F766C
#8F766C
oklch(58.7% 0.035 43)
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 #66818B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Steel Grey #6F828A ΔE 0.013
- Grey Blue #647D8E ΔE 0.015
- Battleship Grey #6B7C85 ΔE 0.015
- Slate Gray #708090 ΔE 0.017
- Steel #738595 ΔE 0.026
- Battleship Gray #6C757D ΔE 0.035
- Medium Grey #7D7F7C ΔE 0.036
- Light Slate Gray #778899 ΔE 0.037
Use #66818B 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.