#257A66
Closest named color: Bluegreen (#017A79). oklch(52.4% 0.086 173.9), rgb(37, 122, 102).
Aa
White text reads best on this color (5.17:1).
About this color
#257A66 is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 52%, its chroma 0.086 and its hue 174°. Its hue sits on the cool side of the wheel. The nearest named color is Bluegreen (#017A79), ΔE 0.031 away. White text reads best on it, at 5.17:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (52%) |
| Chroma | moderately saturated (0.086) |
| Temperature | cool |
| Nearest name | Bluegreen (#017A79) |
| Black text | 4.05:1 |
| White text | 5.17:1 |
Values
| HEX | #257A66 |
| RGB | rgb(37, 122, 102) |
| HSL | hsl(166, 53%, 31%) |
| OKLCH | oklch(52.4% 0.086 173.9) |
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 #257A66 | 5.17:1 | AA | Lc -80.7 | Fine for body text |
| Black text on #257A66 | 4.05:1 | AA large text | Lc 28.7 | Dividers and decoration only |
| #257A66 text on white | 5.17:1 | AA | Lc 75.4 | Fine for body text |
| #257A66 text on black | 4.05:1 | AA large text | Lc -26.4 | 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 600.
-
Step 50
50
#F2F7F5
oklch(97.2% 0.006 170.4)
-
Step 100
100
#E3ECE9
oklch(93.5% 0.01 174.3)
-
Step 200
200
#CBDED8
oklch(88.5% 0.022 174.9)
-
Step 300
300
#A8C9BF
oklch(80.9% 0.038 175)
-
Step 400
400
#77AE9D
oklch(70.7% 0.063 173.1)
-
Step 500
500
#519986
oklch(63% 0.079 174.5)
-
Step 600
600 (this color)
#257A66
oklch(52.4% 0.086 173.9)
-
Step 700
700
#226F5D
oklch(49% 0.08 174.1)
-
Step 800
800
#1F5B4C
oklch(42.8% 0.067 173.6)
-
Step 900
900
#204B3F
oklch(37.8% 0.053 172.7)
-
Step 950
950
#142C25
oklch(27.1% 0.033 172.8)
#257A66 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) | #767265 | 0.090 |
| Deuteranopia (no green cones) | #6A6967 | 0.086 |
| Tritanopia (no blue cones) | #007B74 | 0.022 |
| Achromatopsia (no color) | #6D6D6D | 0.087 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #257A66
#257A66
oklch(52.4% 0.086 173.9)
- #91546D
#91546D
oklch(52.4% 0.087 354.4)
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 #257A66, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Bluegreen #017A79 ΔE 0.031
- Dark Aquamarine #017371 ΔE 0.035
- Teal #008080 ΔE 0.038
- Deep Turquoise #017374 ΔE 0.038
- Deep Aqua #08787F ΔE 0.042
- Dark Aqua #05696B ΔE 0.061
- Dark Cyan #008B8B ΔE 0.064
- Sea Green #2E8B57 ΔE 0.065
Use #257A66 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.