#3F4FCB
Closest named color: Warm Blue (#4B57DB). oklch(49.2% 0.191 271.7), rgb(63, 79, 203).
Aa
White text reads best on this color (6.57:1).
About this color
#3F4FCB is a medium-dark, vivid blue. In OKLCH its lightness is 49%, its chroma 0.191 and its hue 272°. Its hue sits on the cool side of the wheel. The nearest named color is Warm Blue (#4B57DB), ΔE 0.036 away. White text reads best on it, at 6.57:1.
| Hue family | Blues |
| Lightness | medium-dark (49%) |
| Chroma | vivid (0.191) |
| Temperature | cool |
| Nearest name | Warm Blue (#4B57DB) |
| Black text | 3.19:1 |
| White text | 6.57:1 |
Values
| HEX | #3F4FCB |
| RGB | rgb(63, 79, 203) |
| HSL | hsl(233, 57%, 52%) |
| OKLCH | oklch(49.2% 0.191 271.7) |
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 #3F4FCB | 6.57:1 | AA | Lc -87.1 | Fine for body text |
| Black text on #3F4FCB | 3.19:1 | AA large text | Lc 22.0 | Dividers and decoration only |
| #3F4FCB text on white | 6.57:1 | AA | Lc 82.0 | Fine for body text |
| #3F4FCB text on black | 3.19:1 | AA large text | Lc -19.9 | 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 700.
-
Step 50
50
#F2F5FE
oklch(97% 0.012 271.3)
-
Step 100
100
#E3E9FC
oklch(93.5% 0.027 271.9)
-
Step 200
200
#CDD8FC
oklch(88.5% 0.051 271.9)
-
Step 300
300
#ABBEFD
oklch(81% 0.092 271.3)
-
Step 400
400
#8099FC
oklch(70.7% 0.148 271.5)
-
Step 500
500
#637CFA
oklch(63.2% 0.189 271.6)
-
Step 600
600
#4D61E9
oklch(55.7% 0.205 271.6)
-
Step 700
700 (this color)
#3F4FCB
oklch(49.2% 0.191 271.7)
-
Step 800
800
#3341A4
oklch(42.6% 0.159 271.7)
-
Step 900
900
#2C3982
oklch(37.8% 0.123 271.6)
-
Step 950
950
#1A224C
oklch(27.1% 0.078 272.1)
#3F4FCB 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) | #0064CF | 0.056 |
| Deuteranopia (no green cones) | #0057C9 | 0.042 |
| Tritanopia (no blue cones) | #006E85 | 0.154 |
| Achromatopsia (no color) | #5D5D5D | 0.192 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F4FCB
#3F4FCB
oklch(49.2% 0.191 271.7)
- #765E00
#765E00
oklch(49.2% 0.101 91.4)
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 #3F4FCB, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Warm Blue #4B57DB ΔE 0.036
- Blue With A Hint Of Purple #533CC6 ΔE 0.046
- Blue Blue #2242C7 ΔE 0.047
- Majorelle Blue #3F37C9 ΔE 0.049
- Blurple #5539CC ΔE 0.050
- Bluey Purple #6241C7 ΔE 0.056
- Iris #6258C4 ΔE 0.058
- Azul #1D5DEC ΔE 0.062
Use #3F4FCB 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.