#3F5BB4
Closest named color: Mid Blue (#276AB3). oklch(49.8% 0.145 267.8), rgb(63, 91, 180).
Aa
White text reads best on this color (6.23:1).
About this color
#3F5BB4 is a medium-dark, vivid blue. In OKLCH its lightness is 50%, its chroma 0.145 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Mid Blue (#276AB3), ΔE 0.043 away. White text reads best on it, at 6.23:1.
| Hue family | Blues |
| Lightness | medium-dark (50%) |
| Chroma | vivid (0.145) |
| Temperature | cool |
| Nearest name | Mid Blue (#276AB3) |
| Black text | 3.36:1 |
| White text | 6.23:1 |
Values
| HEX | #3F5BB4 |
| RGB | rgb(63, 91, 180) |
| HSL | hsl(226, 48%, 48%) |
| OKLCH | oklch(49.8% 0.145 267.8) |
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 #3F5BB4 | 6.23:1 | AA | Lc -85.9 | Fine for body text |
| Black text on #3F5BB4 | 3.36:1 | AA large text | Lc 23.3 | Dividers and decoration only |
| #3F5BB4 text on white | 6.23:1 | AA | Lc 80.8 | Fine for body text |
| #3F5BB4 text on black | 3.36:1 | AA large text | Lc -21.1 | 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
#F3F5FC
oklch(97.1% 0.01 273.4)
-
Step 100
100
#E4EAF8
oklch(93.7% 0.02 267.3)
-
Step 200
200
#CED9F4
oklch(88.5% 0.039 267.9)
-
Step 300
300
#ADC0EF
oklch(81% 0.07 267.6)
-
Step 400
400
#829EE7
oklch(70.8% 0.112 267.5)
-
Step 500
500
#6484E0
oklch(63.2% 0.143 267.7)
-
Step 600
600
#4C6BCD
oklch(55.5% 0.155 267.9)
-
Step 700
700 (this color)
#3F5BB4
oklch(49.8% 0.145 267.8)
-
Step 800
800
#334990
oklch(42.7% 0.12 268.1)
-
Step 900
900
#2C3E73
oklch(37.7% 0.093 267.7)
-
Step 950
950
#1A2543
oklch(27.1% 0.058 267.3)
#3F5BB4 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) | #2B66B7 | 0.031 |
| Deuteranopia (no green cones) | #0E5CB2 | 0.036 |
| Tritanopia (no blue cones) | #00707F | 0.121 |
| Achromatopsia (no color) | #616161 | 0.145 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F5BB4
#3F5BB4
oklch(49.8% 0.145 267.8)
- #7B5E00
#7B5E00
oklch(49.8% 0.102 87.6)
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 #3F5BB4, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Mid Blue #276AB3 ΔE 0.043
- French Blue #436BAD ΔE 0.048
- Iris #6258C4 ΔE 0.054
- Dusky Blue #475F94 ΔE 0.055
- Denim Blue #3B5B92 ΔE 0.055
- Warm Blue #4B57DB ΔE 0.064
- Twilight #4E518B ΔE 0.068
- Dark Periwinkle #665FD1 ΔE 0.072
Use #3F5BB4 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.