#178B9C
Closest named color: Teal Blue (#01889F). oklch(58.6% 0.097 210.5), rgb(23, 139, 156).
Aa
Black text reads best on this color (5.20:1).
About this color
#178B9C is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 59%, its chroma 0.097 and its hue 211°. Its hue sits on the cool side of the wheel. The nearest named color is Teal Blue (#01889F), ΔE 0.013 away. Black text reads best on it, at 5.20:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Teal Blue (#01889F) |
| Black text | 5.20:1 |
| White text | 4.03:1 |
Values
| HEX | #178B9C |
| RGB | rgb(23, 139, 156) |
| HSL | hsl(188, 74%, 35%) |
| OKLCH | oklch(58.6% 0.097 210.5) |
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 #178B9C | 4.03:1 | AA large text | Lc -72.6 | Content text, not long reading |
| Black text on #178B9C | 5.20:1 | AA | Lc 37.0 | Non-text elements, placeholder text |
| #178B9C text on white | 4.03:1 | AA large text | Lc 67.1 | Content text, not long reading |
| #178B9C text on black | 5.20:1 | AA | Lc -34.5 | 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
#F1F7F8
oklch(97.2% 0.007 208.8)
-
Step 100
100
#E1ECEE
oklch(93.5% 0.012 209.8)
-
Step 200
200
#C8DEE2
oklch(88.5% 0.024 209.8)
-
Step 300
300
#A1C9D0
oklch(80.9% 0.043 209.4)
-
Step 400
400
#6AADB9
oklch(70.7% 0.07 210.1)
-
Step 500
500
#3B98A8
oklch(63.1% 0.089 210.9)
-
Step 600
600 (this color)
#178B9C
oklch(58.6% 0.097 210.5)
-
Step 700
700
#006D7C
oklch(49% 0.085 211.2)
-
Step 800
800
#005A66
oklch(42.9% 0.074 210.4)
-
Step 900
900
#114A53
oklch(37.8% 0.058 210.4)
-
Step 950
950
#0D2B30
oklch(26.9% 0.036 210.1)
#178B9C 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) | #7D869D | 0.090 |
| Deuteranopia (no green cones) | #6C799C | 0.083 |
| Tritanopia (no blue cones) | #009290 | 0.033 |
| Achromatopsia (no color) | #7F7F7F | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178B9C
#178B9C
oklch(58.6% 0.097 210.5)
- #AE6559
#AE6559
oklch(58.6% 0.097 30.2)
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 #178B9C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Teal Blue #01889F ΔE 0.013
- Dark Cyan #008B8B ΔE 0.028
- Teal Green #0A9396 ΔE 0.029
- Blue NCS #118AB2 ΔE 0.036
- Ocean #017B92 ΔE 0.049
- Teal #008080 ΔE 0.050
- Dusty Teal #4C9085 ΔE 0.052
- Cerulean #457B9D ΔE 0.052
Use #178B9C 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.