#427EC1
Closest named color: Windows Blue (#3778BF). oklch(58.4% 0.121 252.8), rgb(66, 126, 193).
Aa
Black text reads best on this color (4.98:1).
About this color
#427EC1 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 58%, its chroma 0.121 and its hue 253°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.021 away. Black text reads best on it, at 4.98:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | moderately saturated (0.121) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.98:1 |
| White text | 4.21:1 |
Values
| HEX | #427EC1 |
| RGB | rgb(66, 126, 193) |
| HSL | hsl(212, 51%, 51%) |
| OKLCH | oklch(58.4% 0.121 252.8) |
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 #427EC1 | 4.21:1 | AA large text | Lc -74.3 | Content text, not long reading |
| Black text on #427EC1 | 4.98:1 | AA | Lc 35.3 | Non-text elements, placeholder text |
| #427EC1 text on white | 4.21:1 | AA large text | Lc 68.8 | Content text, not long reading |
| #427EC1 text on black | 4.98:1 | AA | Lc -32.8 | 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 600.
-
Step 50
50
#F2F6FA
oklch(97.1% 0.007 247.9)
-
Step 100
100
#E3EBF4
oklch(93.7% 0.015 251.2)
-
Step 200
200
#CBDBED
oklch(88.5% 0.03 251.3)
-
Step 300
300
#A8C3E4
oklch(80.8% 0.055 253.6)
-
Step 400
400
#79A4D6
oklch(70.7% 0.087 252.7)
-
Step 500
500
#568DCB
oklch(63.2% 0.111 252.5)
-
Step 600
600 (this color)
#427EC1
oklch(58.4% 0.121 252.8)
-
Step 700
700
#2C629E
oklch(49% 0.112 253.1)
-
Step 800
800
#255180
oklch(42.8% 0.092 252.1)
-
Step 900
900
#234367
oklch(37.7% 0.073 252.7)
-
Step 950
950
#15273C
oklch(26.8% 0.046 253.2)
#427EC1 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) | #6182C4 | 0.036 |
| Deuteranopia (no green cones) | #4F76C0 | 0.023 |
| Tritanopia (no blue cones) | #008E96 | 0.097 |
| Achromatopsia (no color) | #7B7B7B | 0.121 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #427EC1
#427EC1
oklch(58.4% 0.121 252.8)
- #A66E0D
#A66E0D
oklch(58.3% 0.121 72.9)
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 #427EC1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.021
- Cool Blue #4984B8 ΔE 0.026
- Steel Blue #4682B4 ΔE 0.026
- Water Blue #0E87CC ΔE 0.033
- Off Blue #5684AE ΔE 0.043
- Nice Blue #107AB0 ΔE 0.043
- Flat Blue #3C73A8 ΔE 0.046
- Dusty Blue #5A86AD ΔE 0.050
Use #427EC1 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.