#3D666B
Closest named color: Slate (#516572). oklch(48.2% 0.047 205.6), rgb(61, 102, 107).
Aa
White text reads best on this color (6.34:1).
About this color
#3D666B is a medium-dark, muted teal or cyan. In OKLCH its lightness is 48%, its chroma 0.047 and its hue 206°. Its hue sits on the cool side of the wheel. The nearest named color is Slate (#516572), ΔE 0.029 away. White text reads best on it, at 6.34:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (48%) |
| Chroma | muted (0.047) |
| Temperature | cool |
| Nearest name | Slate (#516572) |
| Black text | 3.31:1 |
| White text | 6.34:1 |
Values
| HEX | #3D666B |
| RGB | rgb(61, 102, 107) |
| HSL | hsl(187, 27%, 33%) |
| OKLCH | oklch(48.2% 0.047 205.6) |
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 #3D666B | 6.34:1 | AA | Lc -86.6 | Fine for body text |
| Black text on #3D666B | 3.31:1 | AA large text | Lc 22.6 | Dividers and decoration only |
| #3D666B text on white | 6.34:1 | AA | Lc 81.5 | Fine for body text |
| #3D666B text on black | 3.31:1 | AA large text | Lc -20.4 | 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 700.
-
Step 50
50
#F3F6F6
oklch(97.1% 0.003 197.1)
-
Step 100
100
#E5EBEC
oklch(93.6% 0.007 208.8)
-
Step 200
200
#D0DCDD
oklch(88.6% 0.013 202.9)
-
Step 300
300
#B1C5C8
oklch(80.9% 0.022 207.6)
-
Step 400
400
#87A7AB
oklch(70.6% 0.036 205.7)
-
Step 500
500
#689297
oklch(63.1% 0.046 205.3)
-
Step 600
600
#4F7C82
oklch(55.6% 0.05 206.5)
-
Step 700
700 (this color)
#3D666B
oklch(48.2% 0.047 205.6)
-
Step 800
800
#355559
oklch(42.6% 0.038 205.8)
-
Step 900
900
#2E4649
oklch(37.6% 0.03 205.8)
-
Step 950
950
#1B292B
oklch(26.9% 0.019 207.1)
#3D666B 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) | #60636B | 0.046 |
| Deuteranopia (no green cones) | #585D6B | 0.042 |
| Tritanopia (no blue cones) | #296967 | 0.022 |
| Achromatopsia (no color) | #5F5F5F | 0.047 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3D666B
#3D666B
oklch(48.2% 0.047 205.6)
- #775451
#775451
oklch(48.2% 0.047 24.5)
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 #3D666B, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Slate #516572 ΔE 0.029
- Dark Aqua #05696B ΔE 0.035
- Dark Green Blue #1F6357 ΔE 0.045
- Deep Turquoise #017374 ΔE 0.046
- Dark Aquamarine #017371 ΔE 0.046
- YInMn Blue #415A77 ΔE 0.048
- Petrol #005F6A ΔE 0.048
- Deep Aqua #08787F ΔE 0.057
Use #3D666B 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.