#283987
Closest named color: Cobalt (#1E488F). oklch(37.9% 0.132 269.7), rgb(40, 57, 135).
Aa
White text reads best on this color (10.36:1).
About this color
#283987 is a dark, moderately saturated blue. In OKLCH its lightness is 38%, its chroma 0.132 and its hue 270°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.041 away. White text reads best on it, at 10.36:1.
| Hue family | Blues |
| Lightness | dark (38%) |
| Chroma | moderately saturated (0.132) |
| Temperature | cool |
| Nearest name | Cobalt (#1E488F) |
| Black text | 2.02:1 |
| White text | 10.36:1 |
Values
| HEX | #283987 |
| RGB | rgb(40, 57, 135) |
| HSL | hsl(229, 54%, 34%) |
| OKLCH | oklch(37.9% 0.132 269.7) |
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 #283987 | 10.36:1 | AAA | Lc -97.7 | Preferred for body text |
| Black text on #283987 | 2.02:1 | Fails | Lc 10.3 | Not readable |
| #283987 text on white | 10.36:1 | AAA | Lc 93.7 | Preferred for body text |
| #283987 text on black | 2.02:1 | Fails | Lc -8.8 | 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
#F2F5FF
oklch(97.1% 0.014 272.7)
-
Step 100
100
#E2EAFE
oklch(93.7% 0.028 268.4)
-
Step 200
200
#CBD8FE
oklch(88.5% 0.054 270.4)
-
Step 300
300
#A8BEFF
oklch(80.9% 0.096 269.8)
-
Step 400
400
#7B9AFF
oklch(70.8% 0.152 269.4)
-
Step 500
500
#5C7CFF
oklch(63.1% 0.197 269.6)
-
Step 600
600
#455FF1
oklch(55.6% 0.22 269.9)
-
Step 700
700
#374DD2
oklch(49.1% 0.205 269.7)
-
Step 800
800
#2D40AA
oklch(42.6% 0.17 269.7)
-
Step 900
900 (this color)
#283987
oklch(37.9% 0.132 269.7)
-
Step 950
950
#17224F
oklch(27.1% 0.084 269.7)
#283987 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) | #00448A | 0.036 |
| Deuteranopia (no green cones) | #003C85 | 0.030 |
| Tritanopia (no blue cones) | #004C5A | 0.107 |
| Achromatopsia (no color) | #404040 | 0.132 |
Harmonies
Hue rotations in OKLCH that keep this color's lightness and chroma.
Complementary
The opposite hue (180°).
- #283987
#283987
oklch(37.9% 0.132 269.7)
- #524000
#524000
oklch(38% 0.078 90.6)
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 #283987, closest first.
Similar named colors
The eight closest entries in our named color list, with their ΔE distance.
- Cobalt #1E488F ΔE 0.041
- Twilight Blue #0A437A ΔE 0.042
- Dark Slate Blue #483D8B ΔE 0.051
- Blueberry #464196 ΔE 0.056
- Sapphire #2138AB ΔE 0.060
- Marine Blue #01386A ΔE 0.061
- Light Navy #155084 ΔE 0.065
- Dusk Blue #26538D ΔE 0.072
Use #283987 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.