#255666
Closest named color: Petrol (#005F6A). oklch(42.7% 0.059 222.3), rgb(37, 86, 102).
Aa
White text reads best on this color (8.07:1).
About this color
#255666 is a dark, muted teal or cyan. In OKLCH its lightness is 43%, its chroma 0.059 and its hue 222°. Its hue sits on the cool side of the wheel. The nearest named color is Petrol (#005F6A), ΔE 0.030 away. White text reads best on it, at 8.07:1.
| Hue family | Teals and cyans |
| Lightness | dark (43%) |
| Chroma | muted (0.059) |
| Temperature | cool |
| Nearest name | Petrol (#005F6A) |
| Black text | 2.60:1 |
| White text | 8.07:1 |
Values
| HEX | #255666 |
| RGB | rgb(37, 86, 102) |
| HSL | hsl(195, 47%, 27%) |
| OKLCH | oklch(42.7% 0.059 222.3) |
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 #255666 | 8.07:1 | AAA | Lc -92.5 | Preferred for body text |
| Black text on #255666 | 2.60:1 | Fails | Lc 16.2 | Dividers and decoration only |
| #255666 text on white | 8.07:1 | AAA | Lc 87.8 | Fine for body text |
| #255666 text on black | 2.60:1 | Fails | Lc -14.4 | Not readable |
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 800.
-
Step 50
50
#F2F6F8
oklch(97.1% 0.005 228.8)
-
Step 100
100
#E3EBEF
oklch(93.5% 0.01 228.9)
-
Step 200
200
#CCDCE2
oklch(88.4% 0.019 222.2)
-
Step 300
300
#A9C6D1
oklch(80.9% 0.035 222.7)
-
Step 400
400
#7BA9B9
oklch(70.7% 0.054 221.4)
-
Step 500
500
#5793A8
oklch(63.1% 0.07 222.5)
-
Step 600
600
#397D93
oklch(55.5% 0.076 222)
-
Step 700
700
#2B6A7E
oklch(49.2% 0.071 222.1)
-
Step 800
800 (this color)
#255666
oklch(42.7% 0.059 222.3)
-
Step 900
900
#244753
oklch(37.7% 0.045 222.5)
-
Step 950
950
#162A31
oklch(27.1% 0.029 222.4)
#255666 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) | #4D5467 | 0.048 |
| Deuteranopia (no green cones) | #434D66 | 0.042 |
| Tritanopia (no blue cones) | #005B5B | 0.034 |
| Achromatopsia (no color) | #505050 | 0.059 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #255666
#255666
oklch(42.7% 0.059 222.3)
- #6A4435
#6A4435
oklch(42.6% 0.058 42.3)
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 #255666, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Petrol #005F6A ΔE 0.030
- Deep Teal #00555A ΔE 0.031
- Dark Slate Gray #2F4F4F ΔE 0.038
- YInMn Blue #415A77 ΔE 0.045
- Dark Grey Blue #29465B ΔE 0.050
- Deep Sea Blue #015482 ΔE 0.051
- Charcoal #264653 ΔE 0.053
- Dark Teal #014D4E ΔE 0.053
Use #255666 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.