#3B74CB
Closest named color: Windows Blue (#3778BF). oklch(56.5% 0.148 258.7), rgb(59, 116, 203).
Aa
White text reads best on this color (4.61:1).
About this color
#3B74CB is a medium-dark, vivid blue. In OKLCH its lightness is 56%, its chroma 0.148 and its hue 259°. Its hue sits on the cool side of the wheel. The nearest named color is Windows Blue (#3778BF), ΔE 0.024 away. White text reads best on it, at 4.61:1.
| Hue family | Blues |
| Lightness | medium-dark (56%) |
| Chroma | vivid (0.148) |
| Temperature | cool |
| Nearest name | Windows Blue (#3778BF) |
| Black text | 4.54:1 |
| White text | 4.61:1 |
Values
| HEX | #3B74CB |
| RGB | rgb(59, 116, 203) |
| HSL | hsl(216, 58%, 51%) |
| OKLCH | oklch(56.5% 0.148 258.7) |
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 #3B74CB | 4.61:1 | AA | Lc -77.2 | Fine for body text |
| Black text on #3B74CB | 4.54:1 | AA | Lc 32.3 | Non-text elements, placeholder text |
| #3B74CB text on white | 4.61:1 | AA | Lc 71.8 | Content text, not long reading |
| #3B74CB text on black | 4.54:1 | AA | Lc -29.9 | 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
#E2EAF7
oklch(93.5% 0.02 260.2)
-
Step 200
200
#CBDAF2
oklch(88.5% 0.037 259.8)
-
Step 300
300
#A7C2EC
oklch(80.8% 0.067 259.1)
-
Step 400
400
#77A2E3
oklch(70.7% 0.107 258.4)
-
Step 500
500
#5489DA
oklch(63.1% 0.135 258.6)
-
Step 600
600 (this color)
#3B74CB
oklch(56.5% 0.148 258.7)
-
Step 700
700
#2B5EAD
oklch(49% 0.138 259)
-
Step 800
800
#244D8C
oklch(42.6% 0.114 258.8)
-
Step 900
900
#224170
oklch(37.7% 0.089 258.5)
-
Step 950
950
#152641
oklch(26.9% 0.056 259.3)
#3B74CB 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) | #4A7CCE | 0.028 |
| Deuteranopia (no green cones) | #316FC9 | 0.017 |
| Tritanopia (no blue cones) | #008895 | 0.117 |
| Achromatopsia (no color) | #757575 | 0.148 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3B74CB
#3B74CB
oklch(56.5% 0.148 258.7)
- #9B6C00
#9B6C00
oklch(56.5% 0.118 78.6)
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 #3B74CB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Windows Blue #3778BF ΔE 0.024
- Royal Blue #4169E1 ΔE 0.047
- French Blue #436BAD ΔE 0.049
- Mid Blue #276AB3 ΔE 0.049
- Water Blue #0E87CC ΔE 0.053
- Flat Blue #3C73A8 ΔE 0.055
- Nice Blue #107AB0 ΔE 0.055
- Steel Blue #4682B4 ΔE 0.060
Use #3B74CB 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.