#284E57
Closest named color: Dark Slate Gray (#2F4F4F). oklch(40% 0.046 214.9), rgb(40, 78, 87).
Aa
White text reads best on this color (9.06:1).
About this color
#284E57 is a dark, muted teal or cyan. In OKLCH its lightness is 40%, its chroma 0.046 and its hue 215°. Its hue sits on the cool side of the wheel. The nearest named color is Dark Slate Gray (#2F4F4F), ΔE 0.016 away. White text reads best on it, at 9.06:1.
| Hue family | Teals and cyans |
| Lightness | dark (40%) |
| Chroma | muted (0.046) |
| Temperature | cool |
| Nearest name | Dark Slate Gray (#2F4F4F) |
| Black text | 2.31:1 |
| White text | 9.06:1 |
Values
| HEX | #284E57 |
| RGB | rgb(40, 78, 87) |
| HSL | hsl(191, 37%, 25%) |
| OKLCH | oklch(40% 0.046 214.9) |
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 #284E57 | 9.06:1 | AAA | Lc -95.1 | Preferred for body text |
| Black text on #284E57 | 2.31:1 | Fails | Lc 13.2 | Not readable |
| #284E57 text on white | 9.06:1 | AAA | Lc 90.7 | Preferred for body text |
| #284E57 text on black | 2.31:1 | Fails | Lc -11.6 | 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
#F2F6F7
oklch(97% 0.004 214.3)
-
Step 100
100
#E3ECEE
oklch(93.7% 0.01 212.5)
-
Step 200
200
#CCDDE1
oklch(88.6% 0.019 213.4)
-
Step 300
300
#A8C7CE
oklch(80.9% 0.035 212.9)
-
Step 400
400
#79AAB6
oklch(70.8% 0.055 214.6)
-
Step 500
500
#5495A4
oklch(63.2% 0.07 214.3)
-
Step 600
600
#357F8F
oklch(55.7% 0.076 214.2)
-
Step 700
700
#276B7A
oklch(49.2% 0.071 215)
-
Step 800
800
#225763
oklch(42.7% 0.059 215.1)
-
Step 900
900 (this color)
#284E57
oklch(40% 0.046 214.9)
-
Step 950
950
#152A2F
oklch(27% 0.028 214.7)
#284E57 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) | #474C58 | 0.041 |
| Deuteranopia (no green cones) | #404657 | 0.038 |
| Tritanopia (no blue cones) | #0C5151 | 0.026 |
| Achromatopsia (no color) | #494949 | 0.046 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #284E57
#284E57
oklch(40% 0.046 214.9)
- #5E3F37
#5E3F37
oklch(40.1% 0.046 35.1)
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 #284E57, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Dark Slate Gray #2F4F4F ΔE 0.016
- Charcoal #264653 ΔE 0.026
- Deep Teal #00555A ΔE 0.029
- Dark Grey Blue #29465B ΔE 0.029
- Dark Teal #014D4E ΔE 0.032
- Dark Blue Green #005249 ΔE 0.041
- Charcoal Grey #3C4142 ΔE 0.048
- Petrol #005F6A ΔE 0.055
Use #284E57 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.