#428DCB
Closest named color: Cool Blue (#4984B8). oklch(62.4% 0.12 246.3), rgb(66, 141, 203).
Aa
Black text reads best on this color (5.90:1).
About this color
#428DCB is a medium-light, moderately saturated blue. In OKLCH its lightness is 62%, its chroma 0.120 and its hue 246°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.033 away. Black text reads best on it, at 5.90:1.
| Hue family | Blues |
| Lightness | medium-light (62%) |
| Chroma | moderately saturated (0.120) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.90:1 |
| White text | 3.55:1 |
Values
| HEX | #428DCB |
| RGB | rgb(66, 141, 203) |
| HSL | hsl(207, 57%, 53%) |
| OKLCH | oklch(62.4% 0.12 246.3) |
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 #428DCB | 3.55:1 | AA large text | Lc -68.4 | Content text, not long reading |
| Black text on #428DCB | 5.90:1 | AA | Lc 41.2 | Non-text elements, placeholder text |
| #428DCB text on white | 3.55:1 | AA large text | Lc 62.9 | Content text, not long reading |
| #428DCB text on black | 5.90:1 | AA | Lc -38.8 | 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
#E1EBF5
oklch(93.5% 0.017 248)
-
Step 200
200
#C8DCEE
oklch(88.5% 0.033 245.3)
-
Step 300
300
#A2C5E5
oklch(80.9% 0.059 246.2)
-
Step 400
400
#6EA6D8
oklch(70.6% 0.094 246.5)
-
Step 500
500 (this color)
#428DCB
oklch(62.4% 0.12 246.3)
-
Step 600
600
#1F78BA
oklch(55.5% 0.13 246.3)
-
Step 700
700
#0F65A1
oklch(49.2% 0.121 246.4)
-
Step 800
800
#125382
oklch(42.8% 0.1 245.8)
-
Step 900
900
#184568
oklch(37.8% 0.077 245.6)
-
Step 950
950
#10283D
oklch(26.9% 0.05 247.3)
#428DCB 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) | #718FCE | 0.049 |
| Deuteranopia (no green cones) | #5E82CA | 0.037 |
| Tritanopia (no blue cones) | #009CA3 | 0.089 |
| Achromatopsia (no color) | #888888 | 0.120 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #428DCB
#428DCB
oklch(62.4% 0.12 246.3)
- #B7772B
#B7772B
oklch(62.3% 0.119 66.4)
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 #428DCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.033
- Water Blue #0E87CC ΔE 0.034
- Dark Sky Blue #448EE4 ΔE 0.038
- Faded Blue #658CBB ΔE 0.039
- Steel Blue #4682B4 ΔE 0.041
- Off Blue #5684AE ΔE 0.046
- Dusty Blue #5A86AD ΔE 0.047
- Blue NCS #118AB2 ΔE 0.049
Use #428DCB 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.