#3188BB
Closest named color: Cool Blue (#4984B8). oklch(59.8% 0.112 238.8), rgb(49, 136, 187).
Aa
Black text reads best on this color (5.36:1).
About this color
#3188BB is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.112 and its hue 239°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.019 away. Black text reads best on it, at 5.36:1.
| Hue family | Blues |
| Lightness | medium-dark (60%) |
| Chroma | moderately saturated (0.112) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.36:1 |
| White text | 3.91:1 |
Values
| HEX | #3188BB |
| RGB | rgb(49, 136, 187) |
| HSL | hsl(202, 58%, 46%) |
| OKLCH | oklch(59.8% 0.112 238.8) |
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 #3188BB | 3.91:1 | AA large text | Lc -71.7 | Content text, not long reading |
| Black text on #3188BB | 5.36:1 | AA | Lc 37.9 | Non-text elements, placeholder text |
| #3188BB text on white | 3.91:1 | AA large text | Lc 66.2 | Content text, not long reading |
| #3188BB text on black | 5.36:1 | AA | Lc -35.5 | 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
#E1ECF4
oklch(93.7% 0.016 239.1)
-
Step 200
200
#C7DDEB
oklch(88.6% 0.03 235.7)
-
Step 300
300
#A0C6E1
oklch(80.8% 0.056 239.3)
-
Step 400
400
#6AA8D2
oklch(70.6% 0.089 239.4)
-
Step 500
500 (this color)
#3188BB
oklch(59.8% 0.112 238.8)
-
Step 600
600
#0A7BB2
oklch(55.5% 0.122 238.9)
-
Step 700
700
#006898
oklch(49.2% 0.11 238.7)
-
Step 800
800
#04557C
oklch(42.7% 0.094 238.4)
-
Step 900
900
#134664
oklch(37.6% 0.073 239.3)
-
Step 950
950
#0D293B
oklch(26.9% 0.047 240.1)
#3188BB 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) | #7088BD | 0.061 |
| Deuteranopia (no green cones) | #5D7BBA | 0.049 |
| Tritanopia (no blue cones) | #00959A | 0.075 |
| Achromatopsia (no color) | #818181 | 0.113 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3188BB
#3188BB
oklch(59.8% 0.112 238.8)
- #B16D33
#B16D33
oklch(59.8% 0.113 58.4)
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 #3188BB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.019
- Steel Blue #4682B4 ΔE 0.021
- Blue NCS #118AB2 ΔE 0.022
- Water Blue #0E87CC ΔE 0.029
- Off Blue #5684AE ΔE 0.034
- Dusty Blue #5A86AD ΔE 0.038
- Nice Blue #107AB0 ΔE 0.047
- Windows Blue #3778BF ΔE 0.047
Use #3188BB 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.