#3F55B7
Closest named color: Iris (#6258C4). oklch(48.8% 0.157 270.1), rgb(63, 85, 183).
Aa
White text reads best on this color (6.57:1).
About this color
#3F55B7 is a medium-dark, vivid blue. In OKLCH its lightness is 49%, its chroma 0.157 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Iris (#6258C4), ΔE 0.055 away. White text reads best on it, at 6.57:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.157) |
| Temperature | cool |
| Nearest name | Iris (#6258C4) |
| Black text | 3.19:1 |
| White text | 6.57:1 |
Values
| HEX | #3F55B7 |
| RGB | rgb(63, 85, 183) |
| HSL | hsl(229, 49%, 48%) |
| OKLCH | oklch(48.8% 0.157 270.1) |
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 #3F55B7 | 6.57:1 | AA | Lc -87.3 | Fine for body text |
| Black text on #3F55B7 | 3.19:1 | AA large text | Lc 21.9 | Dividers and decoration only |
| #3F55B7 text on white | 6.57:1 | AA | Lc 82.2 | Fine for body text |
| #3F55B7 text on black | 3.19:1 | AA large text | Lc -19.7 | 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
#E4EAF9
oklch(93.7% 0.021 268.4)
-
Step 200
200
#CED8F6
oklch(88.4% 0.043 270.9)
-
Step 300
300
#ADBFF3
oklch(80.9% 0.076 269.8)
-
Step 400
400
#839CEC
oklch(70.7% 0.121 269.9)
-
Step 500
500
#6681E6
oklch(63.1% 0.155 270.2)
-
Step 600
600
#4F68D4
oklch(55.6% 0.168 270.3)
-
Step 700
700 (this color)
#3F55B7
oklch(48.8% 0.157 270.1)
-
Step 800
800
#354795
oklch(42.8% 0.129 270.3)
-
Step 900
900
#2D3C77
oklch(37.6% 0.102 270.2)
-
Step 950
950
#1A2445
oklch(27% 0.063 269.2)
#3F55B7 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) | #1263BA | 0.044 |
| Deuteranopia (no green cones) | #0058B5 | 0.042 |
| Tritanopia (no blue cones) | #006C7E | 0.129 |
| Achromatopsia (no color) | #5D5D5D | 0.157 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F55B7
#3F55B7
oklch(48.8% 0.157 270.1)
- #765C00
#765C00
oklch(48.7% 0.1 89.5)
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 #3F55B7, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Iris #6258C4 ΔE 0.055
- Mid Blue #276AB3 ΔE 0.058
- Warm Blue #4B57DB ΔE 0.059
- Blue With A Hint Of Purple #533CC6 ΔE 0.063
- Blue Blue #2242C7 ΔE 0.064
- Denim Blue #3B5B92 ΔE 0.064
- French Blue #436BAD ΔE 0.065
- Dusky Blue #475F94 ΔE 0.067
Use #3F55B7 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.