#187CA3
Closest named color: Nice Blue (#107AB0). oklch(55.1% 0.104 230.7), rgb(24, 124, 163).
Aa
White text reads best on this color (4.71:1).
About this color
#187CA3 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.104 and its hue 231°. Its hue sits on the cool side of the wheel. The nearest named color is Nice Blue (#107AB0), ΔE 0.023 away. White text reads best on it, at 4.71:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.104) |
| Temperature | cool |
| Nearest name | Nice Blue (#107AB0) |
| Black text | 4.45:1 |
| White text | 4.71:1 |
Values
| HEX | #187CA3 |
| RGB | rgb(24, 124, 163) |
| HSL | hsl(197, 74%, 37%) |
| OKLCH | oklch(55.1% 0.104 230.7) |
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 #187CA3 | 4.71:1 | AA | Lc -77.8 | Fine for body text |
| Black text on #187CA3 | 4.45:1 | AA large text | Lc 31.8 | Non-text elements, placeholder text |
| #187CA3 text on white | 4.71:1 | AA | Lc 72.3 | Content text, not long reading |
| #187CA3 text on black | 4.45:1 | AA large text | Lc -29.4 | Dividers and decoration only |
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
#F1F6F9
oklch(97% 0.007 233.6)
-
Step 100
100
#E1ECF1
oklch(93.6% 0.014 226.6)
-
Step 200
200
#C9DDE7
oklch(88.6% 0.025 229.2)
-
Step 300
300
#A3C7DA
oklch(81% 0.047 231.1)
-
Step 400
400
#6EAAC7
oklch(70.8% 0.075 230.1)
-
Step 500
500
#4394B9
oklch(63.2% 0.096 230.7)
-
Step 600
600 (this color)
#187CA3
oklch(55.1% 0.104 230.7)
-
Step 700
700
#076A8D
oklch(49.2% 0.096 230.4)
-
Step 800
800
#0F5672
oklch(42.6% 0.08 230.7)
-
Step 900
900
#17475C
oklch(37.6% 0.062 230.6)
-
Step 950
950
#0F2A36
oklch(27% 0.04 229.8)
#187CA3 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) | #687AA5 | 0.070 |
| Deuteranopia (no green cones) | #566EA2 | 0.059 |
| Tritanopia (no blue cones) | #008789 | 0.061 |
| Achromatopsia (no color) | #737373 | 0.104 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #187CA3
#187CA3
oklch(55.1% 0.104 230.7)
- #A15E35
#A15E35
oklch(55% 0.104 50.6)
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 #187CA3, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Nice Blue #107AB0 ΔE 0.023
- Ocean #017B92 ΔE 0.029
- Cerulean #457B9D ΔE 0.030
- Sea Blue #047495 ΔE 0.031
- Muted Blue #3B719F ΔE 0.035
- Ocean Blue #03719C ΔE 0.035
- Flat Blue #3C73A8 ΔE 0.035
- Dull Blue #49759C ΔE 0.036
Use #187CA3 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.