#178C9E
Closest named color: Teal Blue (#01889F). oklch(58.9% 0.098 211.3), rgb(23, 140, 158).
Aa
Black text reads best on this color (5.28:1).
About this color
#178C9E is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 59%, its chroma 0.098 and its hue 211°. Its hue sits on the cool side of the wheel. The nearest named color is Teal Blue (#01889F), ΔE 0.014 away. Black text reads best on it, at 5.28:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (59%) |
| Chroma | moderately saturated (0.098) |
| Temperature | cool |
| Nearest name | Teal Blue (#01889F) |
| Black text | 5.28:1 |
| White text | 3.97:1 |
Values
| HEX | #178C9E |
| RGB | rgb(23, 140, 158) |
| HSL | hsl(188, 75%, 35%) |
| OKLCH | oklch(58.9% 0.098 211.3) |
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 #178C9E | 3.97:1 | AA large text | Lc -72.2 | Content text, not long reading |
| Black text on #178C9E | 5.28:1 | AA | Lc 37.4 | Non-text elements, placeholder text |
| #178C9E text on white | 3.97:1 | AA large text | Lc 66.6 | Content text, not long reading |
| #178C9E text on black | 5.28:1 | AA | Lc -35.0 | 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
#E1ECEF
oklch(93.6% 0.012 215.8)
-
Step 200
200
#C8DEE2
oklch(88.5% 0.024 209.8)
-
Step 300
300
#A1C9D1
oklch(81% 0.044 211.2)
-
Step 400
400
#6AADBA
oklch(70.8% 0.071 211.3)
-
Step 500
500
#3A98A8
oklch(63.1% 0.09 210.7)
-
Step 600
600 (this color)
#178C9E
oklch(58.9% 0.098 211.3)
-
Step 700
700
#006D7C
oklch(49% 0.085 211.2)
-
Step 800
800
#005966
oklch(42.6% 0.074 211.8)
-
Step 900
900
#104A53
oklch(37.8% 0.059 210.3)
-
Step 950
950
#0D2B31
oklch(27% 0.037 212.9)
#178C9E 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) | #7E879F | 0.091 |
| Deuteranopia (no green cones) | #6C7A9E | 0.082 |
| Tritanopia (no blue cones) | #009391 | 0.034 |
| Achromatopsia (no color) | #808080 | 0.098 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178C9E
#178C9E
oklch(58.9% 0.098 211.3)
- #AF6658
#AF6658
oklch(58.9% 0.097 31.7)
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 #178C9E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Teal Blue #01889F ΔE 0.014
- Teal Green #0A9396 ΔE 0.028
- Dark Cyan #008B8B ΔE 0.031
- Blue NCS #118AB2 ΔE 0.034
- Dusty Teal #4C9085 ΔE 0.052
- Ocean #017B92 ΔE 0.052
- Sea #3C9992 ΔE 0.053
- Cerulean #457B9D ΔE 0.053
Use #178C9E 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.