#404F5F
Closest named color: Dark Slate Gray (#2F4F4F). oklch(42.1% 0.033 250.3), rgb(64, 79, 95).
Aa
White text reads best on this color (8.39:1).
About this color
#404F5F is a dark, muted blue. In OKLCH its lightness is 42%, its chroma 0.033 and its hue 250°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Gray (#2F4F4F), ΔE 0.037 away. White text reads best on it, at 8.39:1.
| Hue family | Blues |
| Lightness | dark (42%) |
| Chroma | muted (0.033) |
| Temperature | cool |
| Nearest name | Dark Slate Gray (#2F4F4F) |
| Black text | 2.50:1 |
| White text | 8.39:1 |
Values
| HEX | #404F5F |
| RGB | rgb(64, 79, 95) |
| HSL | hsl(211, 19%, 31%) |
| OKLCH | oklch(42.1% 0.033 250.3) |
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 #404F5F | 8.39:1 | AAA | Lc -93.5 | Preferred for body text |
| Black text on #404F5F | 2.50:1 | Fails | Lc 15.1 | Dividers and decoration only |
| #404F5F text on white | 8.39:1 | AAA | Lc 88.9 | Fine for body text |
| #404F5F text on black | 2.50:1 | Fails | Lc -13.3 | 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
#F4F5F7
oklch(97% 0.003 264.5)
-
Step 100
100
#E7EAED
oklch(93.6% 0.005 247.9)
-
Step 200
200
#D4DAE0
oklch(88.6% 0.011 247.9)
-
Step 300
300
#B8C2CD
oklch(81% 0.019 250.6)
-
Step 400
400
#93A2B4
oklch(70.6% 0.031 253)
-
Step 500
500
#788CA1
oklch(63.2% 0.039 249.7)
-
Step 600
600
#61768C
oklch(55.7% 0.042 249.8)
-
Step 700
700
#506377
oklch(49.2% 0.04 250)
-
Step 800
800 (this color)
#404F5F
oklch(42.1% 0.033 250.3)
-
Step 900
900
#37434F
oklch(37.7% 0.026 248.5)
-
Step 950
950
#21272E
oklch(27% 0.016 252.4)
#404F5F 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) | #494F60 | 0.014 |
| Deuteranopia (no green cones) | #454C5F | 0.011 |
| Tritanopia (no blue cones) | #375354 | 0.029 |
| Achromatopsia (no color) | #4D4D4D | 0.033 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #404F5F
#404F5F
oklch(42.1% 0.033 250.3)
- #594B3A
#594B3A
oklch(42.2% 0.033 72.2)
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 #404F5F, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Gray #2F4F4F ΔE 0.037
- Dark Grey Blue #29465B ΔE 0.044
- YInMn Blue #415A77 ΔE 0.045
- Charcoal #264653 ΔE 0.050
- Dusty Grape #545775 ΔE 0.052
- Deep Teal #00555A ΔE 0.055
- Charcoal Grey #3C4142 ΔE 0.057
- Petrol #005F6A ΔE 0.061
Use #404F5F 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.