#3F51BC
Closest named color: Blue With A Hint Of Purple (#533CC6). oklch(48.4% 0.169 271.4), rgb(63, 81, 188).
Aa
White text reads best on this color (6.74:1).
About this color
#3F51BC is a medium-dark, vivid blue. In OKLCH its lightness is 48%, its chroma 0.169 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Blue With A Hint Of Purple (#533CC6), ΔE 0.052 away. White text reads best on it, at 6.74:1.
| Hue family | Blues |
| Lightness | medium-dark (48%) |
| Chroma | vivid (0.169) |
| Temperature | cool |
| Nearest name | Blue With A Hint Of Purple (#533CC6) |
| Black text | 3.11:1 |
| White text | 6.74:1 |
Values
| HEX | #3F51BC |
| RGB | rgb(63, 81, 188) |
| HSL | hsl(231, 50%, 49%) |
| OKLCH | oklch(48.4% 0.169 271.4) |
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 #3F51BC | 6.74:1 | AA | Lc -87.9 | Fine for body text |
| Black text on #3F51BC | 3.11:1 | AA large text | Lc 21.2 | Dividers and decoration only |
| #3F51BC text on white | 6.74:1 | AA | Lc 82.8 | Fine for body text |
| #3F51BC text on black | 3.11:1 | AA large text | Lc -19.1 | 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 700.
-
Step 50
50
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E4E9FA
oklch(93.5% 0.024 272.8)
-
Step 200
200
#CED8F8
oklch(88.5% 0.045 271.7)
-
Step 300
300
#ADBEF6
oklch(80.8% 0.082 271.4)
-
Step 400
400
#839BF2
oklch(70.8% 0.13 271.1)
-
Step 500
500
#667FED
oklch(63.1% 0.167 271.3)
-
Step 600
600
#5065DB
oklch(55.5% 0.181 271.6)
-
Step 700
700 (this color)
#3F51BC
oklch(48.4% 0.169 271.4)
-
Step 800
800
#35459A
oklch(42.7% 0.139 271.3)
-
Step 900
900
#2E3B7A
oklch(37.7% 0.108 271.6)
-
Step 950
950
#1B2348
oklch(27% 0.069 271.9)
#3F51BC 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) | #0061C0 | 0.050 |
| Deuteranopia (no green cones) | #0056BA | 0.042 |
| Tritanopia (no blue cones) | #006B7E | 0.140 |
| Achromatopsia (no color) | #5B5B5B | 0.169 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F51BC
#3F51BC
oklch(48.4% 0.169 271.4)
- #735C00
#735C00
oklch(48.4% 0.099 91.8)
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 #3F51BC, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blue With A Hint Of Purple #533CC6 ΔE 0.052
- Blue Blue #2242C7 ΔE 0.053
- Warm Blue #4B57DB ΔE 0.053
- Iris #6258C4 ΔE 0.056
- Majorelle Blue #3F37C9 ΔE 0.059
- Blurple #5539CC ΔE 0.060
- Bluey Purple #6241C7 ΔE 0.061
- Mid Blue #276AB3 ΔE 0.069
Use #3F51BC 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.