#4271A5
Closest named color: Flat Blue (#3C73A8). oklch(53.9% 0.097 252.2), rgb(66, 113, 165).
Aa
White text reads best on this color (5.07:1).
About this color
#4271A5 is a medium-dark, moderately saturated blue. In OKLCH its lightness is 54%, its chroma 0.097 and its hue 252°. Its hue sits on the cool side of the wheel. The nearest named color is Flat Blue (#3C73A8), ΔE 0.008 away. White text reads best on it, at 5.07:1.
| Hue family | Blues |
| Lightness | medium-dark (54%) |
| Chroma | moderately saturated (0.097) |
| Temperature | cool |
| Nearest name | Flat Blue (#3C73A8) |
| Black text | 4.13:1 |
| White text | 5.07:1 |
Values
| HEX | #4271A5 |
| RGB | rgb(66, 113, 165) |
| HSL | hsl(212, 43%, 45%) |
| OKLCH | oklch(53.9% 0.097 252.2) |
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 #4271A5 | 5.07:1 | AA | Lc -80.3 | Fine for body text |
| Black text on #4271A5 | 4.13:1 | AA large text | Lc 29.2 | Dividers and decoration only |
| #4271A5 text on white | 5.07:1 | AA | Lc 74.9 | Content text, not long reading |
| #4271A5 text on black | 4.13:1 | AA large text | Lc -26.8 | 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
#F3F6F9
oklch(97.2% 0.005 247.9)
-
Step 100
100
#E4EBF2
oklch(93.7% 0.012 248)
-
Step 200
200
#CEDBE9
oklch(88.6% 0.024 250.1)
-
Step 300
300
#ADC3DD
oklch(80.9% 0.044 252.7)
-
Step 400
400
#81A4CB
oklch(70.7% 0.069 251.5)
-
Step 500
500
#618DBE
oklch(63.2% 0.089 251.9)
-
Step 600
600 (this color)
#4271A5
oklch(53.9% 0.097 252.2)
-
Step 700
700
#386392
oklch(49.1% 0.09 252)
-
Step 800
800
#2F5177
oklch(42.7% 0.075 252.4)
-
Step 900
900
#2A4360
oklch(37.6% 0.059 253)
-
Step 950
950
#192838
oklch(27.1% 0.036 250.8)
#4271A5 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) | #5B74A7 | 0.031 |
| Deuteranopia (no green cones) | #4E6AA4 | 0.022 |
| Tritanopia (no blue cones) | #007D83 | 0.082 |
| Achromatopsia (no color) | #6E6E6E | 0.097 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #4271A5
#4271A5
oklch(53.9% 0.097 252.2)
- #916425
#916425
oklch(53.9% 0.097 71.8)
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 #4271A5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Flat Blue #3C73A8 ΔE 0.008
- Muted Blue #3B719F ΔE 0.012
- Dull Blue #49759C ΔE 0.022
- French Blue #436BAD ΔE 0.024
- Cerulean #457B9D ΔE 0.036
- Nice Blue #107AB0 ΔE 0.036
- Stormy Blue #507B9C ΔE 0.040
- Ocean Blue #03719C ΔE 0.040
Use #4271A5 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.