#3F77E5
Closest named color: Royal Blue (#4169E1). oklch(59% 0.177 262.1), rgb(63, 119, 229).
Aa
Black text reads best on this color (4.98:1).
About this color
#3F77E5 is a medium-dark, vivid blue. In OKLCH its lightness is 59%, its chroma 0.177 and its hue 262°. 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 4.98:1.
| Hue family | Blues |
| Lightness | medium-dark (59%) |
| Chroma | vivid (0.177) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.98:1 |
| White text | 4.21:1 |
Values
| HEX | #3F77E5 |
| RGB | rgb(63, 119, 229) |
| HSL | hsl(220, 76%, 57%) |
| OKLCH | oklch(59% 0.177 262.1) |
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 #3F77E5 | 4.21:1 | AA large text | Lc -74.2 | Content text, not long reading |
| Black text on #3F77E5 | 4.98:1 | AA | Lc 35.4 | Non-text elements, placeholder text |
| #3F77E5 text on white | 4.21:1 | AA large text | Lc 68.7 | Content text, not long reading |
| #3F77E5 text on black | 4.98:1 | AA | Lc -33.0 | 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
#F2F6FD
oklch(97.2% 0.01 261.8)
-
Step 100
100
#E2EAFA
oklch(93.6% 0.023 264.5)
-
Step 200
200
#C9DAF7
oklch(88.5% 0.044 261.2)
-
Step 300
300
#A5C1F5
oklch(80.9% 0.08 262.6)
-
Step 400
400
#749FF0
oklch(70.6% 0.128 262.3)
-
Step 500
500
#5185EB
oklch(63.1% 0.163 262.4)
-
Step 600
600 (this color)
#3F77E5
oklch(59% 0.177 262.1)
-
Step 700
700
#285ABC
oklch(49.1% 0.164 262)
-
Step 800
800
#224A98
oklch(42.7% 0.136 262)
-
Step 900
900
#203F79
oklch(37.8% 0.106 261.6)
-
Step 950
950
#132547
oklch(26.9% 0.068 261.9)
#3F77E5 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) | #3983E9 | 0.030 |
| Deuteranopia (no green cones) | #0074E3 | 0.033 |
| Tritanopia (no blue cones) | #0091A3 | 0.140 |
| Achromatopsia (no color) | #7B7B7B | 0.178 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F77E5
#3F77E5
oklch(59% 0.177 262.1)
- #A17500
#A17500
oklch(59.1% 0.122 82.2)
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 #3F77E5, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.035
- Clear Blue #247AFD ΔE 0.038
- Cerulean Blue #056EEE ΔE 0.043
- Neon Blue #4361EE ΔE 0.055
- Cornflower #6A79F7 ΔE 0.056
- Windows Blue #3778BF ΔE 0.060
- Dark Sky Blue #448EE4 ΔE 0.062
- Soft Blue #6488EA ΔE 0.063
Use #3F77E5 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.