#428CDD
Closest named color: Dark Sky Blue (#448EE4). oklch(63.1% 0.143 252.8), rgb(66, 140, 221).
Aa
Black text reads best on this color (6.02:1).
About this color
#428CDD is a medium-light, vivid blue. In OKLCH its lightness is 63%, its chroma 0.143 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Sky Blue (#448EE4), ΔE 0.011 away. Black text reads best on it, at 6.02:1.
| Hue family | Blues |
| Lightness | medium-light (63%) |
| Chroma | vivid (0.143) |
| Temperature | cool |
| Nearest name | Dark Sky Blue (#448EE4) |
| Black text | 6.02:1 |
| White text | 3.48:1 |
Values
| HEX | #428CDD |
| RGB | rgb(66, 140, 221) |
| HSL | hsl(211, 70%, 56%) |
| OKLCH | oklch(63.1% 0.143 252.8) |
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 #428CDD | 3.48:1 | AA large text | Lc -67.6 | Content text, not long reading |
| Black text on #428CDD | 6.02:1 | AA | Lc 42.0 | Non-text elements, placeholder text |
| #428CDD text on white | 3.48:1 | AA large text | Lc 62.1 | Content text, not long reading |
| #428CDD text on black | 6.02:1 | AA | Lc -39.6 | 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
#E1EBF7
oklch(93.6% 0.019 252.9)
-
Step 200
200
#C8DBF3
oklch(88.5% 0.039 254.3)
-
Step 300
300
#A1C4ED
oklch(80.9% 0.069 252.7)
-
Step 400
400
#6CA4E5
oklch(70.7% 0.113 253)
-
Step 500
500 (this color)
#428CDD
oklch(63.1% 0.143 252.8)
-
Step 600
600
#1C74CB
oklch(55.6% 0.156 252.9)
-
Step 700
700
#0C61AF
oklch(49.1% 0.144 252.7)
-
Step 800
800
#10508E
oklch(42.8% 0.119 252.5)
-
Step 900
900
#174371
oklch(37.8% 0.092 252.4)
-
Step 950
950
#0F2742
oklch(26.9% 0.059 253.1)
#428CDD 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) | #6791E0 | 0.040 |
| Deuteranopia (no green cones) | #5083DB | 0.025 |
| Tritanopia (no blue cones) | #009FAA | 0.110 |
| Achromatopsia (no color) | #898989 | 0.143 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #428CDD
#428CDD
oklch(63.1% 0.143 252.8)
- #BA7A00
#BA7A00
oklch(63.1% 0.135 72.7)
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 #428CDD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Sky Blue #448EE4 ΔE 0.011
- Chefchaouen Blue #4895EF ΔE 0.034
- Soft Blue #6488EA ΔE 0.040
- Water Blue #0E87CC ΔE 0.041
- Cornflower Blue #6495ED ΔE 0.048
- Dodger Blue #1E90FF ΔE 0.052
- Cool Blue #4984B8 ΔE 0.056
- Faded Blue #658CBB ΔE 0.059
Use #428CDD 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.