#4271BA
Closest named color: Windows Blue (#3778BF). oklch(55.1% 0.125 258.9), rgb(66, 113, 186).
Aa
White text reads best on this color (4.88:1).
About this color
#4271BA is a medium-dark, moderately saturated blue. In OKLCH its lightness is 55%, its chroma 0.125 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.020 away. White text reads best on it, at 4.88:1.
| Hue family | Blues |
| Lightness | medium-dark (55%) |
| Chroma | moderately saturated (0.125) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.30:1 |
| White text | 4.88:1 |
Values
| HEX | #4271BA |
| RGB | rgb(66, 113, 186) |
| HSL | hsl(217, 48%, 49%) |
| OKLCH | oklch(55.1% 0.125 258.9) |
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 #4271BA | 4.88:1 | AA | Lc -79.0 | Fine for body text |
| Black text on #4271BA | 4.30:1 | AA large text | Lc 30.5 | Non-text elements, placeholder text |
| #4271BA text on white | 4.88:1 | AA | Lc 73.6 | Content text, not long reading |
| #4271BA text on black | 4.30:1 | AA large text | Lc -28.1 | Dividers and decoration only |
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
#F2F6FB
oklch(97.2% 0.008 253.9)
-
Step 100
100
#E3EAF5
oklch(93.5% 0.017 259.4)
-
Step 200
200
#CDDAEE
oklch(88.5% 0.031 258.9)
-
Step 300
300
#ABC2E6
oklch(80.9% 0.057 259.3)
-
Step 400
400
#7EA2D9
oklch(70.7% 0.09 258.7)
-
Step 500
500
#5D8ACF
oklch(63.1% 0.116 258.7)
-
Step 600
600 (this color)
#4271BA
oklch(55.1% 0.125 258.9)
-
Step 700
700
#3560A2
oklch(49.2% 0.117 258.7)
-
Step 800
800
#2C4E83
oklch(42.6% 0.097 259)
-
Step 900
900
#284269
oklch(37.8% 0.074 258.3)
-
Step 950
950
#18273E
oklch(27.2% 0.048 258.7)
#4271BA 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) | #5177BD | 0.025 |
| Deuteranopia (no green cones) | #3F6CB8 | 0.015 |
| Tritanopia (no blue cones) | #00828C | 0.105 |
| Achromatopsia (no color) | #717171 | 0.125 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4271BA
#4271BA
oklch(55.1% 0.125 258.9)
- #956800
#956800
oklch(55% 0.114 78.8)
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 #4271BA, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.020
- French Blue #436BAD ΔE 0.024
- Flat Blue #3C73A8 ΔE 0.031
- Mid Blue #276AB3 ΔE 0.034
- Nice Blue #107AB0 ΔE 0.043
- Muted Blue #3B719F ΔE 0.044
- Dull Blue #49759C ΔE 0.052
- Steel Blue #4682B4 ΔE 0.052
Use #4271BA 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.