#3F455C
Closest named color: Dark Grey Blue (#29465B). oklch(39.5% 0.04 273.1), rgb(63, 69, 92).
Aa
White text reads best on this color (9.47:1).
About this color
#3F455C is a dark, muted blue. In OKLCH its lightness is 39%, its chroma 0.040 and its hue 273°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Grey Blue (#29465B), ΔE 0.030 away. White text reads best on it, at 9.47:1.
| Hue family | Blues |
| Lightness | dark (39%) |
| Chroma | muted (0.040) |
| Temperature | cool |
| Nearest name | Dark Grey Blue (#29465B) |
| Black text | 2.21:1 |
| White text | 9.47:1 |
Values
| HEX | #3F455C |
| RGB | rgb(63, 69, 92) |
| HSL | hsl(228, 19%, 30%) |
| OKLCH | oklch(39.5% 0.04 273.1) |
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 #3F455C | 9.47:1 | AAA | Lc -96.2 | Preferred for body text |
| Black text on #3F455C | 2.21:1 | Fails | Lc 12.0 | Not readable |
| #3F455C text on white | 9.47:1 | AAA | Lc 91.9 | Preferred for body text |
| #3F455C text on black | 2.21:1 | Fails | Lc -10.5 | 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 900.
-
Step 50
50
#F4F5F8
oklch(97% 0.004 271.4)
-
Step 100
100
#E8EAF0
oklch(93.7% 0.008 271.3)
-
Step 200
200
#D5D9E4
oklch(88.5% 0.016 270)
-
Step 300
300
#BAC0D5
oklch(81% 0.03 273)
-
Step 400
400
#969FBF
oklch(70.6% 0.048 272.8)
-
Step 500
500
#7D87AF
oklch(63% 0.061 273.6)
-
Step 600
600
#66719B
oklch(55.6% 0.067 272.8)
-
Step 700
700
#555E84
oklch(49% 0.062 273.7)
-
Step 800
800
#464D6B
oklch(42.7% 0.051 273.9)
-
Step 900
900 (this color)
#3F455C
oklch(39.5% 0.04 273.1)
-
Step 950
950
#222633
oklch(27.1% 0.025 271.4)
#3F455C 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) | #3E475D | 0.006 |
| Deuteranopia (no green cones) | #3C455B | 0.005 |
| Tritanopia (no blue cones) | #37494D | 0.035 |
| Achromatopsia (no color) | #464646 | 0.040 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F455C
#3F455C
oklch(39.5% 0.04 273.1)
- #4D462D
#4D462D
oklch(39.4% 0.04 94.3)
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 #3F455C, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Grey Blue #29465B ΔE 0.030
- Charcoal #264653 ΔE 0.039
- Charcoal Grey #3C4142 ΔE 0.044
- Dark Slate Gray #2F4F4F ΔE 0.049
- Onyx #343A40 ΔE 0.057
- Dark Blue Grey #1F3B4D ΔE 0.062
- Dark Teal #014D4E ΔE 0.069
- YInMn Blue #415A77 ΔE 0.069
Use #3F455C 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.