#178EBC
Closest named color: Blue NCS (#118AB2). oklch(60.8% 0.118 231.3), rgb(23, 142, 188).
Aa
Black text reads best on this color (5.63:1).
About this color
#178EBC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.118 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.018 away. Black text reads best on it, at 5.63:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.118) |
| Temperature | cool |
| Nearest name | Blue NCS (#118AB2) |
| Black text | 5.63:1 |
| White text | 3.72:1 |
Values
| HEX | #178EBC |
| RGB | rgb(23, 142, 188) |
| HSL | hsl(197, 78%, 41%) |
| OKLCH | oklch(60.8% 0.118 231.3) |
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 #178EBC | 3.72:1 | AA large text | Lc -69.9 | Content text, not long reading |
| Black text on #178EBC | 5.63:1 | AA | Lc 39.7 | Non-text elements, placeholder text |
| #178EBC text on white | 3.72:1 | AA large text | Lc 64.4 | Content text, not long reading |
| #178EBC text on black | 5.63:1 | AA | Lc -37.3 | 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
#F1F6FA
oklch(97.1% 0.008 241.7)
-
Step 100
100
#DFECF3
oklch(93.5% 0.017 230.9)
-
Step 200
200
#C5DDEB
oklch(88.4% 0.032 233.3)
-
Step 300
300
#9BC8DF
oklch(80.9% 0.057 230.5)
-
Step 400
400
#60ABD0
oklch(70.7% 0.092 231.5)
-
Step 500
500 (this color)
#178EBC
oklch(60.8% 0.118 231.3)
-
Step 600
600
#007EA9
oklch(55.6% 0.112 231.2)
-
Step 700
700
#006A8F
oklch(49.2% 0.1 231.3)
-
Step 800
800
#005776
oklch(42.8% 0.087 231.2)
-
Step 900
900
#004863
oklch(37.7% 0.077 231.8)
-
Step 950
950
#062A3A
oklch(26.9% 0.049 232.2)
#178EBC 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) | #778CBE | 0.078 |
| Deuteranopia (no green cones) | #627EBB | 0.066 |
| Tritanopia (no blue cones) | #009A9E | 0.067 |
| Achromatopsia (no color) | #848484 | 0.118 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178EBC
#178EBC
oklch(60.8% 0.118 231.3)
- #B96C3B
#B96C3B
oklch(60.8% 0.117 51.3)
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 #178EBC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue NCS #118AB2 ΔE 0.018
- Water Blue #0E87CC ΔE 0.036
- Cool Blue #4984B8 ΔE 0.036
- Steel Blue #4682B4 ΔE 0.038
- Off Blue #5684AE ΔE 0.046
- Teal Blue #01889F ΔE 0.046
- Dusty Blue #5A86AD ΔE 0.048
- Faded Blue #658CBB ΔE 0.056
Use #178EBC 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.