#428ABD
Closest named color: Cool Blue (#4984B8). oklch(61% 0.106 242.2), rgb(66, 138, 189).
Aa
Black text reads best on this color (5.60:1).
About this color
#428ABD is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.106 and its hue 242°. Its hue sits on the cool side of the wheel. The nearest named color is Cool Blue (#4984B8), ΔE 0.017 away. Black text reads best on it, at 5.60:1.
| Hue family | Blues |
| Lightness | medium-dark (61%) |
| Chroma | moderately saturated (0.106) |
| Temperature | cool |
| Nearest name | Cool Blue (#4984B8) |
| Black text | 5.60:1 |
| White text | 3.74:1 |
Values
| HEX | #428ABD |
| RGB | rgb(66, 138, 189) |
| HSL | hsl(205, 48%, 50%) |
| OKLCH | oklch(61% 0.106 242.2) |
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 #428ABD | 3.74:1 | AA large text | Lc -70.3 | Content text, not long reading |
| Black text on #428ABD | 5.60:1 | AA | Lc 39.3 | Non-text elements, placeholder text |
| #428ABD text on white | 3.74:1 | AA large text | Lc 64.8 | Content text, not long reading |
| #428ABD text on black | 5.60:1 | AA | Lc -36.9 | 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
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E2EBF3
oklch(93.6% 0.015 244.7)
-
Step 200
200
#C9DCEB
oklch(88.5% 0.029 241.6)
-
Step 300
300
#A4C5E0
oklch(80.8% 0.052 243.1)
-
Step 400
400
#71A7D0
oklch(70.6% 0.083 242.1)
-
Step 500
500 (this color)
#428ABD
oklch(61% 0.106 242.2)
-
Step 600
600
#267AB1
oklch(55.6% 0.116 242.4)
-
Step 700
700
#176698
oklch(49% 0.108 242.7)
-
Step 800
800
#17547B
oklch(42.8% 0.088 241.8)
-
Step 900
900
#1B4563
oklch(37.6% 0.069 242.8)
-
Step 950
950
#11293A
oklch(27% 0.044 241.7)
#428ABD 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) | #738BBF | 0.052 |
| Deuteranopia (no green cones) | #627EBC | 0.043 |
| Tritanopia (no blue cones) | #00979C | 0.078 |
| Achromatopsia (no color) | #848484 | 0.106 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #428ABD
#428ABD
oklch(61% 0.106 242.2)
- #B0733A
#B0733A
oklch(60.9% 0.106 61.6)
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 #428ABD, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cool Blue #4984B8 ΔE 0.017
- Steel Blue #4682B4 ΔE 0.023
- Off Blue #5684AE ΔE 0.028
- Dusty Blue #5A86AD ΔE 0.030
- Blue NCS #118AB2 ΔE 0.033
- Faded Blue #658CBB ΔE 0.036
- Water Blue #0E87CC ΔE 0.036
- Windows Blue #3778BF ΔE 0.055
Use #428ABD 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.