#3688D2
Closest named color: Water Blue (#0E87CC). oklch(61.2% 0.137 249.2), rgb(54, 136, 210).
Aa
Black text reads best on this color (5.60:1).
About this color
#3688D2 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.137 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Water Blue (#0E87CC), ΔE 0.021 away. Black text reads best on it, at 5.60:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.137) |
| Temperature | cool |
| Nearest name | Water Blue (#0E87CC) |
| Black text | 5.60:1 |
| White text | 3.74:1 |
Values
| HEX | #3688D2 |
| RGB | rgb(54, 136, 210) |
| HSL | hsl(208, 63%, 52%) |
| OKLCH | oklch(61.2% 0.137 249.2) |
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 #3688D2 | 3.74:1 | AA large text | Lc -70.1 | Content text, not long reading |
| Black text on #3688D2 | 5.60:1 | AA | Lc 39.4 | Non-text elements, placeholder text |
| #3688D2 text on white | 3.74:1 | AA large text | Lc 64.6 | Content text, not long reading |
| #3688D2 text on black | 5.60:1 | AA | Lc -37.0 | 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
#F1F6FB
oklch(97.1% 0.009 247.9)
-
Step 100
100
#E0EBF7
oklch(93.5% 0.02 250.4)
-
Step 200
200
#C7DCF1
oklch(88.5% 0.037 248.2)
-
Step 300
300
#A0C5EB
oklch(81% 0.067 249.3)
-
Step 400
400
#6AA6E1
oklch(70.8% 0.107 249.2)
-
Step 500
500 (this color)
#3688D2
oklch(61.2% 0.137 249.2)
-
Step 600
600
#0E76C6
oklch(55.5% 0.15 249.4)
-
Step 700
700
#0063AA
oklch(49.1% 0.137 249.4)
-
Step 800
800
#06518A
oklch(42.6% 0.115 249.1)
-
Step 900
900
#13446F
oklch(37.8% 0.09 249.2)
-
Step 950
950
#0D2841
oklch(27% 0.057 249.3)
#3688D2 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) | #668CD5 | 0.047 |
| Deuteranopia (no green cones) | #4F7DD1 | 0.033 |
| Tritanopia (no blue cones) | #009AA3 | 0.102 |
| Achromatopsia (no color) | #848484 | 0.137 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3688D2
#3688D2
oklch(61.2% 0.137 249.2)
- #B67300
#B67300
oklch(61.3% 0.133 69.7)
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 #3688D2, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Water Blue #0E87CC ΔE 0.021
- Dark Sky Blue #448EE4 ΔE 0.033
- Cool Blue #4984B8 ΔE 0.040
- Steel Blue #4682B4 ΔE 0.046
- Windows Blue #3778BF ΔE 0.049
- Chefchaouen Blue #4895EF ΔE 0.056
- Blue NCS #118AB2 ΔE 0.056
- Faded Blue #658CBB ΔE 0.057
Use #3688D2 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.