#666E78
Closest named color: Battleship Gray (#6C757D). oklch(53.5% 0.018 254), rgb(102, 110, 120).
Aa
White text reads best on this color (5.16:1).
About this color
#666E78 is a medium-dark close to neutral grey. In OKLCH its lightness is 53%, its chroma 0.018. It has too little chroma to lean warm or cool. The nearest named color is Battleship Gray (#6C757D), ΔE 0.023 away. White text reads best on it, at 5.16:1.
| Hue family | Neutrals |
| Lightness | medium-dark (53%) |
| Chroma | close to neutral grey (0.018) |
| Temperature | neutral |
| Nearest name | Battleship Gray (#6C757D) |
| Black text | 4.06:1 |
| White text | 5.16:1 |
Values
| HEX | #666E78 |
| RGB | rgb(102, 110, 120) |
| HSL | hsl(213, 8%, 44%) |
| OKLCH | oklch(53.5% 0.018 254) |
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 #666E78 | 5.16:1 | AA | Lc -81.0 | Fine for body text |
| Black text on #666E78 | 4.06:1 | AA large text | Lc 28.5 | Dividers and decoration only |
| #666E78 text on white | 5.16:1 | AA | Lc 75.6 | Fine for body text |
| #666E78 text on black | 4.06:1 | AA large text | Lc -26.1 | 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
#F5F5F6
oklch(97% 0.001 286.4)
-
Step 100
100
#E9EAEB
oklch(93.7% 0.002 247.8)
-
Step 200
200
#D7D9DC
oklch(88.5% 0.005 258.3)
-
Step 300
300
#BDC1C6
oklch(80.9% 0.008 253.9)
-
Step 400
400
#9BA1A9
oklch(70.7% 0.014 255.5)
-
Step 500
500
#838A94
oklch(63.1% 0.017 257.2)
-
Step 600
600 (this color)
#666E78
oklch(53.5% 0.018 254)
-
Step 700
700
#5A616B
oklch(49% 0.018 257.2)
-
Step 800
800
#4A5057
oklch(42.8% 0.014 252.2)
-
Step 900
900
#3E4247
oklch(37.7% 0.01 254)
-
Step 950
950
#24272A
oklch(27.1% 0.007 248.1)
#666E78 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) | #6B6E79 | 0.008 |
| Deuteranopia (no green cones) | #696C78 | 0.007 |
| Tritanopia (no blue cones) | #627071 | 0.016 |
| Achromatopsia (no color) | #6D6D6D | 0.018 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #666E78
#666E78
oklch(53.5% 0.018 254)
- #746C62
#746C62
oklch(53.6% 0.018 73.5)
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 #666E78, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Battleship Gray #6C757D ΔE 0.023
- Dim Gray #696969 ΔE 0.023
- Metallic Blue #4F738E ΔE 0.041
- Battleship Grey #6B7C85 ΔE 0.042
- Slate #516572 ΔE 0.042
- Grey Blue #647D8E ΔE 0.047
- Purple Grey #866F85 ΔE 0.055
- Grey Purple #826D8C ΔE 0.056
Use #666E78 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.