#283F95
Closest named color: Cobalt (#1E488F). oklch(40.4% 0.144 268), rgb(40, 63, 149).
Aa
White text reads best on this color (9.39:1).
About this color
#283F95 is a dark, vivid blue. In OKLCH its lightness is 40%, its chroma 0.144 and its hue 268°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.027 away. White text reads best on it, at 9.39:1.
| Hue family | Blues |
| Lightness | dark (40%) |
| Chroma | vivid (0.144) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.23:1 |
| White text | 9.39:1 |
Values
| HEX | #283F95 |
| RGB | rgb(40, 63, 149) |
| HSL | hsl(227, 58%, 37%) |
| OKLCH | oklch(40.4% 0.144 268) |
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 #283F95 | 9.39:1 | AAA | Lc -95.6 | Preferred for body text |
| Black text on #283F95 | 2.23:1 | Fails | Lc 12.7 | Not readable |
| #283F95 text on white | 9.39:1 | AAA | Lc 91.3 | Preferred for body text |
| #283F95 text on black | 2.23:1 | Fails | Lc -11.1 | 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
#F2F5FD
oklch(97% 0.011 269.6)
-
Step 100
100
#E3EAFB
oklch(93.7% 0.024 267.9)
-
Step 200
200
#CCD9F9
oklch(88.6% 0.046 267.9)
-
Step 300
300
#A9BFF8
oklch(80.8% 0.085 268.1)
-
Step 400
400
#7C9CF4
oklch(70.6% 0.134 267.8)
-
Step 500
500
#5D81F0
oklch(63.2% 0.171 267.8)
-
Step 600
600
#4567DF
oklch(55.6% 0.187 267.9)
-
Step 700
700
#3755C2
oklch(49.2% 0.174 267.8)
-
Step 800
800 (this color)
#283F95
oklch(40.4% 0.144 268)
-
Step 900
900
#283C7C
oklch(37.7% 0.111 267.7)
-
Step 950
950
#182449
oklch(27.2% 0.071 268)
#283F95 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) | #004C98 | 0.038 |
| Deuteranopia (no green cones) | #004193 | 0.027 |
| Tritanopia (no blue cones) | #005463 | 0.116 |
| Achromatopsia (no color) | #464646 | 0.144 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283F95
#283F95
oklch(40.4% 0.144 268)
- #5B4500
#5B4500
oklch(40.3% 0.082 87.8)
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 #283F95, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.027
- Sapphire #2138AB ΔE 0.041
- Blueberry #464196 ΔE 0.043
- Dark Slate Blue #483D8B ΔE 0.047
- Twilight Blue #0A437A ΔE 0.054
- Dusk Blue #26538D ΔE 0.058
- Light Navy #155084 ΔE 0.058
- Deep Sea Blue #015482 ΔE 0.072
Use #283F95 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.