#403F99
Closest named color: Blueberry (#464196). oklch(42.2% 0.143 278.8), rgb(64, 63, 153).
Aa
White text reads best on this color (8.79:1).
About this color
#403F99 is a dark, vivid blue. In OKLCH its lightness is 42%, its chroma 0.143 and its hue 279°. Its hue sits on the cool side of the wheel. The nearest named color is Blueberry (#464196), ΔE 0.012 away. White text reads best on it, at 8.79:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | vivid (0.143) |
| Temperature | cool |
| Nearest name | Blueberry (#464196) |
| Black text | 2.38:1 |
| White text | 8.79:1 |
Values
| HEX | #403F99 |
| RGB | rgb(64, 63, 153) |
| HSL | hsl(241, 42%, 42%) |
| OKLCH | oklch(42.2% 0.143 278.8) |
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 #403F99 | 8.79:1 | AAA | Lc -94.2 | Preferred for body text |
| Black text on #403F99 | 2.38:1 | Fails | Lc 14.2 | Not readable |
| #403F99 text on white | 8.79:1 | AAA | Lc 89.7 | Fine for body text |
| #403F99 text on black | 2.38:1 | Fails | Lc -12.5 | Not readable |
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
#F3F5FD
oklch(97.1% 0.011 274.9)
-
Step 100
100
#E6E9FA
oklch(93.7% 0.023 277.9)
-
Step 200
200
#D2D7F8
oklch(88.6% 0.046 278.6)
-
Step 300
300
#B4BCF7
oklch(81% 0.084 278.4)
-
Step 400
400
#8F96F2
oklch(70.6% 0.134 279.1)
-
Step 500
500
#7679EE
oklch(63.1% 0.172 279.1)
-
Step 600
600
#605FDC
oklch(55.5% 0.186 278.8)
-
Step 700
700
#504EBF
oklch(49.2% 0.172 278.8)
-
Step 800
800 (this color)
#403F99
oklch(42.2% 0.143 278.8)
-
Step 900
900
#37387B
oklch(37.8% 0.111 279)
-
Step 950
950
#202148
oklch(27% 0.071 279.4)
#403F99 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) | #004E9C | 0.059 |
| Deuteranopia (no green cones) | #004797 | 0.056 |
| Tritanopia (no blue cones) | #0C5465 | 0.124 |
| Achromatopsia (no color) | #4B4B4B | 0.143 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #403F99
#403F99
oklch(42.2% 0.143 278.8)
- #5A4E00
#5A4E00
oklch(42.3% 0.088 99.1)
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 #403F99, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Blueberry #464196 ΔE 0.012
- Dark Slate Blue #483D8B ΔE 0.026
- Cobalt #1E488F ΔE 0.047
- Sapphire #2138AB ΔE 0.054
- Twilight #4E518B ΔE 0.062
- Dusk Blue #26538D ΔE 0.064
- Rebecca Purple #663399 ΔE 0.069
- Light Navy #155084 ΔE 0.073
Use #403F99 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.