#3990DF
Closest named color: Dark Sky Blue (#448EE4). oklch(63.8% 0.145 249.4), rgb(57, 144, 223).
Aa
Black text reads best on this color (6.22:1).
About this color
#3990DF is a medium-light, vivid blue. In OKLCH its lightness is 64%, its chroma 0.145 and its hue 249°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.013 away. Black text reads best on it, at 6.22:1.
| Hue family | Blues |
| Lightness | medium-light (64%) |
| Chroma | vivid (0.145) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.22:1 |
| White text | 3.37:1 |
Values
| HEX | #3990DF |
| RGB | rgb(57, 144, 223) |
| HSL | hsl(209, 72%, 55%) |
| OKLCH | oklch(63.8% 0.145 249.4) |
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 #3990DF | 3.37:1 | AA large text | Lc -66.3 | Content text, not long reading |
| Black text on #3990DF | 6.22:1 | AA | Lc 43.3 | Non-text elements, placeholder text |
| #3990DF text on white | 3.37:1 | AA large text | Lc 60.8 | Content text, not long reading |
| #3990DF text on black | 6.22:1 | AA | Lc -40.9 | 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
#F1F6FC
oklch(97.1% 0.01 252.8)
-
Step 100
100
#E0EBF7
oklch(93.5% 0.02 250.4)
-
Step 200
200
#C6DCF3
oklch(88.5% 0.04 249.5)
-
Step 300
300
#9EC5ED
oklch(80.9% 0.071 249.4)
-
Step 400
400
#66A6E4
oklch(70.8% 0.113 249)
-
Step 500
500 (this color)
#3990DF
oklch(63.8% 0.145 249.4)
-
Step 600
600
#0076C9
oklch(55.6% 0.155 249.4)
-
Step 700
700
#0063AA
oklch(49.1% 0.137 249.4)
-
Step 800
800
#00518D
oklch(42.7% 0.12 249.5)
-
Step 900
900
#0E4471
oklch(37.8% 0.094 249)
-
Step 950
950
#0B2842
oklch(27% 0.059 248.9)
#3990DF 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) | #6C94E2 | 0.049 |
| Deuteranopia (no green cones) | #5385DD | 0.033 |
| Tritanopia (no blue cones) | #00A3AD | 0.107 |
| Achromatopsia (no color) | #8C8C8C | 0.145 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3990DF
#3990DF
oklch(63.8% 0.145 249.4)
- #C17A00
#C17A00
oklch(64% 0.139 69.5)
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 #3990DF, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.013
- Chefchaouen Blue #4895EF ΔE 0.030
- Water Blue #0E87CC ΔE 0.043
- Soft Blue #6488EA ΔE 0.046
- Cornflower Blue #6495ED ΔE 0.047
- Dodger Blue #1E90FF ΔE 0.049
- Cool Blue #4984B8 ΔE 0.061
- Faded Blue #658CBB ΔE 0.062
Use #3990DF 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.