#3777E1
Closest named color: Royal Blue (#4169E1). oklch(58.4% 0.175 260), rgb(55, 119, 225).
Aa
Black text reads best on this color (4.88:1).
About this color
#3777E1 is a medium-dark, vivid blue. In OKLCH its lightness is 58%, its chroma 0.175 and its hue 260°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.035 away. Black text reads best on it, at 4.88:1.
| Hue family | Blues |
| Lightness | medium-dark (58%) |
| Chroma | vivid (0.175) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.88:1 |
| White text | 4.29:1 |
Values
| HEX | #3777E1 |
| RGB | rgb(55, 119, 225) |
| HSL | hsl(217, 74%, 55%) |
| OKLCH | oklch(58.4% 0.175 260) |
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 #3777E1 | 4.29:1 | AA large text | Lc -74.8 | Content text, not long reading |
| Black text on #3777E1 | 4.88:1 | AA | Lc 34.8 | Non-text elements, placeholder text |
| #3777E1 text on white | 4.29:1 | AA large text | Lc 69.3 | Content text, not long reading |
| #3777E1 text on black | 4.88:1 | AA | Lc -32.4 | 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
#F1F6FD
oklch(97.1% 0.011 256.7)
-
Step 100
100
#E1EBFA
oklch(93.7% 0.023 258.4)
-
Step 200
200
#C9DAF7
oklch(88.5% 0.044 261.2)
-
Step 300
300
#A3C2F4
oklch(80.9% 0.079 259.9)
-
Step 400
400
#71A1EE
oklch(70.7% 0.125 259.5)
-
Step 500
500
#4C87E9
oklch(63.2% 0.16 260)
-
Step 600
600 (this color)
#3777E1
oklch(58.4% 0.175 260)
-
Step 700
700
#215BBB
oklch(49% 0.163 260.1)
-
Step 800
800
#1D4B97
oklch(42.7% 0.135 260)
-
Step 900
900
#1D4078
oklch(37.8% 0.104 259.4)
-
Step 950
950
#122646
oklch(27.1% 0.065 259.4)
#3777E1 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) | #3C82E5 | 0.030 |
| Deuteranopia (no green cones) | #0473DF | 0.027 |
| Tritanopia (no blue cones) | #0090A1 | 0.136 |
| Achromatopsia (no color) | #7A7A7A | 0.175 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3777E1
#3777E1
oklch(58.4% 0.175 260)
- #A17200
#A17200
oklch(58.5% 0.121 79.9)
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 #3777E1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.035
- Cerulean Blue #056EEE ΔE 0.041
- Clear Blue #247AFD ΔE 0.042
- Windows Blue #3778BF ΔE 0.053
- Neon Blue #4361EE ΔE 0.058
- Water Blue #0E87CC ΔE 0.060
- Dark Sky Blue #448EE4 ΔE 0.064
- Cornflower #6A79F7 ΔE 0.065
Use #3777E1 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.