#178FAC
Closest named color: Blue NCS (#118AB2). oklch(60.3% 0.105 219.8), rgb(23, 143, 172).
Aa
Black text reads best on this color (5.56:1).
About this color
#178FAC is a medium-dark, moderately saturated teal or cyan. In OKLCH its lightness is 60%, its chroma 0.105 and its hue 220°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.020 away. Black text reads best on it, at 5.56:1.
| Hue family | Teals and cyans |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.105) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 5.56:1 |
| White text | 3.77:1 |
Values
| HEX | #178FAC |
| RGB | rgb(23, 143, 172) |
| HSL | hsl(192, 76%, 38%) |
| OKLCH | oklch(60.3% 0.105 219.8) |
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 #178FAC | 3.77:1 | AA large text | Lc -70.3 | Content text, not long reading |
| Black text on #178FAC | 5.56:1 | AA | Lc 39.3 | Non-text elements, placeholder text |
| #178FAC text on white | 3.77:1 | AA large text | Lc 64.8 | Content text, not long reading |
| #178FAC text on black | 5.56:1 | AA | Lc -36.8 | 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 500.
-
Step 50
50
#F1F7F9
oklch(97.2% 0.007 219.6)
-
Step 100
100
#E0ECF1
oklch(93.6% 0.015 224.5)
-
Step 200
200
#C5DEE6
oklch(88.5% 0.029 219)
-
Step 300
300
#9CC9D8
oklch(80.9% 0.052 220.3)
-
Step 400
400
#61ADC4
oklch(70.7% 0.082 219.7)
-
Step 500
500 (this color)
#178FAC
oklch(60.3% 0.105 219.8)
-
Step 600
600
#00809C
oklch(55.5% 0.101 220.3)
-
Step 700
700
#006C83
oklch(49.1% 0.089 219.3)
-
Step 800
800
#00586C
oklch(42.6% 0.078 220.2)
-
Step 900
900
#004A5A
oklch(37.8% 0.068 218.5)
-
Step 950
950
#072B35
oklch(26.9% 0.043 220.5)
#178FAC 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) | #7D8BAE | 0.087 |
| Deuteranopia (no green cones) | #6A7DAC | 0.078 |
| Tritanopia (no blue cones) | #009898 | 0.047 |
| Achromatopsia (no color) | #838383 | 0.105 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178FAC
#178FAC
oklch(60.3% 0.105 219.8)
- #B66A50
#B66A50
oklch(60.3% 0.105 39.6)
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 #178FAC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.020
- Teal Blue #01889F ΔE 0.027
- Teal Green #0A9396 ΔE 0.040
- Steel Blue #4682B4 ΔE 0.048
- Cool Blue #4984B8 ΔE 0.049
- Dusty Blue #5A86AD ΔE 0.050
- Off Blue #5684AE ΔE 0.050
- Dark Cyan #008B8B ΔE 0.052
Use #178FAC 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.