#3F70D1
Closest named color: Royal Blue (#4169E1). oklch(56.2% 0.159 262.3), rgb(63, 112, 209).
Aa
White text reads best on this color (4.71:1).
About this color
#3F70D1 is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.159 and its hue 262°. Its hue sits on the cool side of the wheel. The nearest named color is Royal Blue (#4169E1), ΔE 0.032 away. White text reads best on it, at 4.71:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.159) |
| Temperature | cool |
| Nearest name | Royal Blue (#4169E1) |
| Black text | 4.44:1 |
| White text | 4.71:1 |
Values
| HEX | #3F70D1 |
| RGB | rgb(63, 112, 209) |
| HSL | hsl(220, 61%, 53%) |
| OKLCH | oklch(56.2% 0.159 262.3) |
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 #3F70D1 | 4.71:1 | AA | Lc -77.9 | Fine for body text |
| Black text on #3F70D1 | 4.44:1 | AA large text | Lc 31.7 | Non-text elements, placeholder text |
| #3F70D1 text on white | 4.71:1 | AA | Lc 72.4 | Content text, not long reading |
| #3F70D1 text on black | 4.44:1 | AA large text | Lc -29.3 | 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
#CBDAF4
oklch(88.5% 0.039 261.5)
-
Step 300
300
#A8C1F0
oklch(80.9% 0.072 262.9)
-
Step 400
400
#7AA0E8
oklch(70.7% 0.114 262.5)
-
Step 500
500
#5886E1
oklch(63% 0.146 262.7)
-
Step 600
600 (this color)
#3F70D1
oklch(56.2% 0.159 262.3)
-
Step 700
700
#305CB3
oklch(49.2% 0.147 262.2)
-
Step 800
800
#284B91
oklch(42.6% 0.123 262.4)
-
Step 900
900
#253F74
oklch(37.6% 0.096 262.9)
-
Step 950
950
#162544
oklch(26.9% 0.061 263.4)
#3F70D1 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) | #3E7BD5 | 0.029 |
| Deuteranopia (no green cones) | #1D6DCF | 0.027 |
| Tritanopia (no blue cones) | #008796 | 0.129 |
| Achromatopsia (no color) | #737373 | 0.159 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F70D1
#3F70D1
oklch(56.2% 0.159 262.3)
- #966D00
#966D00
oklch(56.1% 0.116 82.4)
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 #3F70D1, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Royal Blue #4169E1 ΔE 0.032
- Windows Blue #3778BF ΔE 0.039
- Cerulean Blue #056EEE ΔE 0.053
- Mid Blue #276AB3 ΔE 0.054
- French Blue #436BAD ΔE 0.056
- Dark Periwinkle #665FD1 ΔE 0.058
- Neon Blue #4361EE ΔE 0.059
- Warm Blue #4B57DB ΔE 0.064
Use #3F70D1 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.