#178DED
Closest named color: Dark Sky Blue (#448EE4). oklch(63.3% 0.172 250.2), rgb(23, 141, 237).
Aa
Black text reads best on this color (6.06:1).
About this color
#178DED is a medium-light, vivid blue. In OKLCH its lightness is 63%, its chroma 0.172 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.027 away. Black text reads best on it, at 6.06:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | vivid (0.172) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.06:1 |
| White text | 3.46:1 |
Values
| HEX | #178DED |
| RGB | rgb(23, 141, 237) |
| HSL | hsl(207, 86%, 51%) |
| OKLCH | oklch(63.3% 0.172 250.2) |
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 #178DED | 3.46:1 | AA large text | Lc -67.0 | Content text, not long reading |
| Black text on #178DED | 6.06:1 | AA | Lc 42.6 | Non-text elements, placeholder text |
| #178DED text on white | 3.46:1 | AA large text | Lc 61.5 | Content text, not long reading |
| #178DED text on black | 6.06:1 | AA | Lc -40.2 | 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
#F0F6FD
oklch(97.1% 0.011 252.1)
-
Step 100
100
#DEECFA
oklch(93.7% 0.024 248.1)
-
Step 200
200
#C3DCF8
oklch(88.5% 0.047 251.3)
-
Step 300
300
#97C5F6
oklch(80.9% 0.085 250.5)
-
Step 400
400
#59A5F1
oklch(70.6% 0.135 250.3)
-
Step 500
500 (this color)
#178DED
oklch(63.3% 0.172 250.2)
-
Step 600
600
#0075CB
oklch(55.5% 0.159 250.4)
-
Step 700
700
#0063AC
oklch(49.2% 0.139 250)
-
Step 800
800
#00518E
oklch(42.8% 0.121 249.9)
-
Step 900
900
#004378
oklch(37.8% 0.108 250.3)
-
Step 950
950
#042747
oklch(26.8% 0.071 250.5)
#178DED 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) | #5C94F1 | 0.052 |
| Deuteranopia (no green cones) | #3882EB | 0.030 |
| Tritanopia (no blue cones) | #00A4B1 | 0.125 |
| Achromatopsia (no color) | #8A8A8A | 0.172 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #178DED
#178DED
oklch(63.3% 0.172 250.2)
- #BE7900
#BE7900
oklch(63.4% 0.137 70.2)
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 #178DED, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.027
- Dodger Blue #1E90FF ΔE 0.028
- Chefchaouen Blue #4895EF ΔE 0.037
- Water Blue #0E87CC ΔE 0.051
- Soft Blue #6488EA ΔE 0.053
- Clear Blue #247AFD ΔE 0.057
- Cornflower Blue #6495ED ΔE 0.060
- Cornflower #6A79F7 ΔE 0.077
Use #178DED 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.