#3A66C6
Closest named color: Mid Blue (#276AB3). oklch(53.1% 0.158 263.5), rgb(58, 102, 198).
Aa
White text reads best on this color (5.39:1).
About this color
#3A66C6 is a medium-dark, vivid blue. In OKLCH its lightness is 53%, its chroma 0.158 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.037 away. White text reads best on it, at 5.39:1.
| Hue family | Blues |
| Lightness | medium-dark (53%) |
| Chroma | vivid (0.158) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.89:1 |
| White text | 5.39:1 |
Values
| HEX | #3A66C6 |
| RGB | rgb(58, 102, 198) |
| HSL | hsl(221, 55%, 50%) |
| OKLCH | oklch(53.1% 0.158 263.5) |
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 #3A66C6 | 5.39:1 | AA | Lc -81.8 | Fine for body text |
| Black text on #3A66C6 | 3.89:1 | AA large text | Lc 27.6 | Dividers and decoration only |
| #3A66C6 text on white | 5.39:1 | AA | Lc 76.5 | Fine for body text |
| #3A66C6 text on black | 3.89:1 | AA large text | Lc -25.2 | 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
#E3EAF8
oklch(93.6% 0.02 264.5)
-
Step 200
200
#CCDAF4
oklch(88.6% 0.039 262.9)
-
Step 300
300
#A9C1EF
oklch(80.9% 0.07 263.3)
-
Step 400
400
#7CA0E8
oklch(70.8% 0.113 263.5)
-
Step 500
500
#5A86E1
oklch(63.1% 0.146 263.3)
-
Step 600
600 (this color)
#3A66C6
oklch(53.1% 0.158 263.5)
-
Step 700
700
#335BB3
oklch(49.1% 0.147 263.5)
-
Step 800
800
#2B4B91
oklch(42.8% 0.122 263.6)
-
Step 900
900
#263F73
oklch(37.6% 0.094 263.2)
-
Step 950
950
#172544
oklch(27% 0.061 264.4)
#3A66C6 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) | #3171CA | 0.029 |
| Deuteranopia (no green cones) | #0464C4 | 0.032 |
| Tritanopia (no blue cones) | #007D8C | 0.128 |
| Achromatopsia (no color) | #6A6A6A | 0.158 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3A66C6
#3A66C6
oklch(53.1% 0.158 263.5)
- #8A6500
#8A6500
oklch(53% 0.109 83.3)
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 #3A66C6, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.037
- Royal Blue #4169E1 ΔE 0.043
- French Blue #436BAD ΔE 0.045
- Windows Blue #3778BF ΔE 0.052
- Warm Blue #4B57DB ΔE 0.052
- Iris #6258C4 ΔE 0.056
- Dark Periwinkle #665FD1 ΔE 0.058
- Neon Blue #4361EE ΔE 0.064
Use #3A66C6 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.