#3F525F
Closest named color: Dark Slate Gray (#2F4F4F). oklch(42.8% 0.032 238.4), rgb(63, 82, 95).
Aa
White text reads best on this color (8.12:1).
About this color
#3F525F is a dark, muted blue. In OKLCH its lightness is 43%, its chroma 0.032 and its hue 238°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Gray (#2F4F4F), ΔE 0.036 away. White text reads best on it, at 8.12:1.
| Hue family | Blues |
| Lightness | dark (43%) |
| Chroma | muted (0.032) |
| Temperature | cool |
| Nearest name | Dark Slate Gray (#2F4F4F) |
| Black text | 2.58:1 |
| White text | 8.12:1 |
Values
| HEX | #3F525F |
| RGB | rgb(63, 82, 95) |
| HSL | hsl(204, 20%, 31%) |
| OKLCH | oklch(42.8% 0.032 238.4) |
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 #3F525F | 8.12:1 | AAA | Lc -92.8 | Preferred for body text |
| Black text on #3F525F | 2.58:1 | Fails | Lc 15.9 | Dividers and decoration only |
| #3F525F text on white | 8.12:1 | AAA | Lc 88.1 | Fine for body text |
| #3F525F text on black | 2.58:1 | Fails | Lc -14.0 | 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
#F4F6F7
oklch(97.2% 0.003 228.8)
-
Step 100
100
#E7EAED
oklch(93.6% 0.005 247.9)
-
Step 200
200
#D3DADF
oklch(88.4% 0.01 238.5)
-
Step 300
300
#B6C3CC
oklch(81% 0.019 237.8)
-
Step 400
400
#90A4B1
oklch(70.7% 0.029 236.4)
-
Step 500
500
#758D9E
oklch(63.1% 0.038 239.1)
-
Step 600
600
#5D7789
oklch(55.6% 0.041 238.7)
-
Step 700
700
#4C6474
oklch(49% 0.039 237.8)
-
Step 800
800 (this color)
#3F525F
oklch(42.8% 0.032 238.4)
-
Step 900
900
#35444E
oklch(37.8% 0.026 237.6)
-
Step 950
950
#1F282D
oklch(27% 0.016 232.4)
#3F525F 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) | #4C5260 | 0.019 |
| Deuteranopia (no green cones) | #484E5F | 0.017 |
| Tritanopia (no blue cones) | #355556 | 0.025 |
| Achromatopsia (no color) | #4F4F4F | 0.032 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #3F525F
#3F525F
oklch(42.8% 0.032 238.4)
- #5D4B3E
#5D4B3E
oklch(42.8% 0.032 57.6)
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 #3F525F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Gray #2F4F4F ΔE 0.036
- YInMn Blue #415A77 ΔE 0.042
- Dusty Grape #545775 ΔE 0.050
- Dark Grey Blue #29465B ΔE 0.050
- Deep Teal #00555A ΔE 0.051
- Petrol #005F6A ΔE 0.054
- Charcoal #264653 ΔE 0.054
- Dusk #4E5481 ΔE 0.062
Use #3F525F 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.