#3747B8
Closest named color: Blue Blue (#2242C7). oklch(45.7% 0.178 271.3), rgb(55, 71, 184).
Aa
White text reads best on this color (7.62:1).
About this color
#3747B8 is a medium-dark, vivid blue. In OKLCH its lightness is 46%, its chroma 0.178 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Blue Blue (#2242C7), ΔE 0.035 away. White text reads best on it, at 7.62:1.
| Hue family | Blues |
| Lightness | medium-dark (46%) |
| Chroma | vivid (0.178) |
| Temperature | cool |
| Nearest name | Blue Blue (#2242C7) |
| Black text | 2.75:1 |
| White text | 7.62:1 |
Values
| HEX | #3747B8 |
| RGB | rgb(55, 71, 184) |
| HSL | hsl(233, 54%, 47%) |
| OKLCH | oklch(45.7% 0.178 271.3) |
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 #3747B8 | 7.62:1 | AAA | Lc -90.8 | Preferred for body text |
| Black text on #3747B8 | 2.75:1 | Fails | Lc 18.1 | Dividers and decoration only |
| #3747B8 text on white | 7.62:1 | AAA | Lc 85.9 | Fine for body text |
| #3747B8 text on black | 2.75:1 | Fails | Lc -16.1 | 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 800.
-
Step 50
50
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E2E9FF
oklch(93.5% 0.031 271.7)
-
Step 200
200
#CBD8FF
oklch(88.5% 0.056 270.7)
-
Step 300
300
#AABEFF
oklch(81% 0.095 271)
-
Step 400
400
#7F99FF
oklch(70.8% 0.152 271.3)
-
Step 500
500
#607AFF
oklch(63% 0.199 271.3)
-
Step 600
600
#485BF7
oklch(55.5% 0.231 271.2)
-
Step 700
700
#3B49D7
oklch(49% 0.214 271.3)
-
Step 800
800 (this color)
#3747B8
oklch(45.7% 0.178 271.3)
-
Step 900
900
#29368A
oklch(37.6% 0.14 271.3)
-
Step 950
950
#182151
oklch(27.1% 0.088 271.3)
#3747B8 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) | #005ABC | 0.051 |
| Deuteranopia (no green cones) | #004EB6 | 0.037 |
| Tritanopia (no blue cones) | #006478 | 0.145 |
| Achromatopsia (no color) | #545454 | 0.178 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3747B8
#3747B8
oklch(45.7% 0.178 271.3)
- #6A5400
#6A5400
oklch(45.5% 0.093 91.2)
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 #3747B8, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue Blue #2242C7 ΔE 0.035
- Majorelle Blue #3F37C9 ΔE 0.041
- Blue With A Hint Of Purple #533CC6 ΔE 0.048
- Sapphire #2138AB ΔE 0.052
- Blurple #5539CC ΔE 0.057
- Blueberry #464196 ΔE 0.059
- Bluey Purple #6241C7 ΔE 0.068
- Cobalt #1E488F ΔE 0.073
Use #3747B8 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.