#333F4E
Closest named color: Onyx (#343A40). oklch(36.3% 0.031 254.2), rgb(51, 63, 78).
Aa
White text reads best on this color (10.70:1).
About this color
#333F4E is a dark, muted blue. In OKLCH its lightness is 36%, its chroma 0.031 and its hue 254°. Its hue sits on the cool side of the wheel. The nearest named color is Onyx (#343A40), ΔE 0.025 away. White text reads best on it, at 10.70:1.
| Hue family | Blues |
| Lightness | dark (36%) |
| Chroma | muted (0.031) |
| Temperature | cool |
| Nearest name | Onyx (#343A40) |
| Black text | 1.96:1 |
| White text | 10.70:1 |
Values
| HEX | #333F4E |
| RGB | rgb(51, 63, 78) |
| HSL | hsl(213, 21%, 25%) |
| OKLCH | oklch(36.3% 0.031 254.2) |
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 #333F4E | 10.70:1 | AAA | Lc -98.7 | Preferred for body text |
| Black text on #333F4E | 1.96:1 | Fails | Lc 9.1 | Not readable |
| #333F4E text on white | 10.70:1 | AAA | Lc 94.8 | Preferred for body text |
| #333F4E text on black | 1.96:1 | Fails | Lc -7.8 | 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
#F4F5F7
oklch(97% 0.003 264.5)
-
Step 100
100
#E7EAEE
oklch(93.6% 0.006 255.5)
-
Step 200
200
#D4DAE2
oklch(88.6% 0.013 255.5)
-
Step 300
300
#B7C2D0
oklch(81% 0.023 254.4)
-
Step 400
400
#91A2B8
oklch(70.6% 0.038 254.9)
-
Step 500
500
#768BA6
oklch(63% 0.048 254.8)
-
Step 600
600
#5F7591
oklch(55.6% 0.051 254.7)
-
Step 700
700
#4E627B
oklch(49% 0.047 254.3)
-
Step 800
800
#405064
oklch(42.6% 0.039 254.2)
-
Step 900
900 (this color)
#333F4E
oklch(36.3% 0.031 254.2)
-
Step 950
950
#202730
oklch(27% 0.02 254.8)
#333F4E 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) | #3A3F4F | 0.011 |
| Deuteranopia (no green cones) | #373D4E | 0.008 |
| Tritanopia (no blue cones) | #2B4244 | 0.026 |
| Achromatopsia (no color) | #3E3E3E | 0.031 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #333F4E
#333F4E
oklch(36.3% 0.031 254.2)
- #483C2C
#483C2C
oklch(36.4% 0.031 74.6)
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 #333F4E, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Onyx #343A40 ΔE 0.025
- Charcoal #264653 ΔE 0.025
- Charcoal Grey #3C4142 ΔE 0.027
- Dark Grey Blue #29465B ΔE 0.028
- Dark Blue Grey #1F3B4D ΔE 0.031
- Gunmetal #293241 ΔE 0.048
- Midnight Green #073B4C ΔE 0.049
- Prussian Blue #1D3557 ΔE 0.052
Use #333F4E 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.