#3771CE
Closest named color: Windows Blue (#3778BF). oklch(55.9% 0.156 259.5), rgb(55, 113, 206).
Aa
White text reads best on this color (4.75:1).
About this color
#3771CE is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.156 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.033 away. White text reads best on it, at 4.75:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.156) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.41:1 |
| White text | 4.75:1 |
Values
| HEX | #3771CE |
| RGB | rgb(55, 113, 206) |
| HSL | hsl(217, 61%, 51%) |
| OKLCH | oklch(55.9% 0.156 259.5) |
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 #3771CE | 4.75:1 | AA | Lc -78.1 | Fine for body text |
| Black text on #3771CE | 4.41:1 | AA large text | Lc 31.4 | Non-text elements, placeholder text |
| #3771CE text on white | 4.75:1 | AA | Lc 72.6 | Content text, not long reading |
| #3771CE text on black | 4.41:1 | AA large text | Lc -29.0 | 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
#F2F6FC
oklch(97.2% 0.009 258.3)
-
Step 100
100
#E2EAF8
oklch(93.5% 0.021 261.8)
-
Step 200
200
#CADAF4
oklch(88.4% 0.04 260.1)
-
Step 300
300
#A6C2EF
oklch(80.9% 0.071 259.8)
-
Step 400
400
#76A1E7
oklch(70.7% 0.113 259.8)
-
Step 500
500
#5288DF
oklch(63% 0.144 259.5)
-
Step 600
600 (this color)
#3771CE
oklch(55.9% 0.156 259.5)
-
Step 700
700
#295DB1
oklch(49% 0.145 259.6)
-
Step 800
800
#234D90
oklch(42.8% 0.12 259.4)
-
Step 900
900
#214073
oklch(37.6% 0.095 259.8)
-
Step 950
950
#142643
oklch(27% 0.059 259.5)
#3771CE 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) | #417AD2 | 0.027 |
| Deuteranopia (no green cones) | #216CCC | 0.022 |
| Tritanopia (no blue cones) | #008795 | 0.124 |
| Achromatopsia (no color) | #737373 | 0.156 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3771CE
#3771CE
oklch(55.9% 0.156 259.5)
- #986B00
#986B00
oklch(56% 0.116 79.5)
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 #3771CE, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.033
- Royal Blue #4169E1 ΔE 0.038
- Mid Blue #276AB3 ΔE 0.048
- French Blue #436BAD ΔE 0.051
- Cerulean Blue #056EEE ΔE 0.054
- Water Blue #0E87CC ΔE 0.061
- Flat Blue #3C73A8 ΔE 0.061
- Nice Blue #107AB0 ΔE 0.061
Use #3771CE 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.