#283589

Closest named color: Cobalt (#1E488F). oklch(37.3% 0.14 271.2), rgb(40, 53, 137).

Aa

White text reads best on this color (10.71:1).

About this color

#283589 is a dark, moderately saturated blue. In OKLCH its lightness is 37%, its chroma 0.140 and its hue 271°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.050 away. White text reads best on it, at 10.71:1.

Hue familyBlues
Lightnessdark (37%)
Chromamoderately saturated (0.140)
Temperaturecool
Nearest nameCobalt (#1E488F)
Black text1.96:1
White text10.71:1

Values

HEX#283589
RGBrgb(40, 53, 137)
HSLhsl(232, 55%, 35%)
OKLCHoklch(37.3% 0.14 271.2)

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.

PairWCAG 2ResultAPCAAPCA guidance
White text on #283589 10.71:1 AAA Lc -98.3 Preferred for body text
Black text on #283589 1.96:1 Fails Lc 9.5 Not readable
#283589 text on white 10.71:1 AAA Lc 94.4 Preferred for body text
#283589 text on black 1.96:1 Fails Lc -8.2 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.

  1. Step 50

    50

    #F2F5FF

    oklch(97.1% 0.014 272.7)

  2. Step 100

    100

    #E2E9FF

    oklch(93.5% 0.031 271.7)

  3. Step 200

    200

    #CBD8FF

    oklch(88.5% 0.056 270.7)

  4. Step 300

    300

    #AABEFF

    oklch(81% 0.095 271)

  5. Step 400

    400

    #7E99FF

    oklch(70.7% 0.152 270.9)

  6. Step 500

    500

    #607BFF

    oklch(63.2% 0.197 271)

  7. Step 600

    600

    #485BF8

    oklch(55.6% 0.232 271.2)

  8. Step 700

    700

    #3A49D9

    oklch(49.2% 0.217 271)

  9. Step 800

    800

    #303DAF

    oklch(42.7% 0.18 271.3)

  10. Step 900

    900 (this color)

    #283589

    oklch(37.3% 0.14 271.2)

  11. Step 950

    950

    #182151

    oklch(27.1% 0.088 271.3)

Export this scale for Tailwind in the Tailwind colors tool

#283589 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.

VisionSeen asShift (ΔE)
Protanopia (no red cones)#00428C0.039
Deuteranopia (no green cones)#003A870.031
Tritanopia (no blue cones)#004A590.114
Achromatopsia (no color)#3E3E3E0.140

Harmonies

Hue rotations in OKLCH that keep this color's lightness and chroma.

Complementary

The opposite hue (180°).

  • #283589

    #283589

    oklch(37.3% 0.14 271.2)

  • #503E00

    #503E00

    oklch(37.3% 0.076 90.1)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #283589

    #283589

    oklch(37.3% 0.14 271.2)

  • #00456A

    #00456A

    oklch(37.3% 0.087 241.1)

  • #4F267D

    #4F267D

    oklch(37.3% 0.141 301.5)

Open the analogous palette in the generator

Split complementary

The two hues beside the complement (150° and 210°).

  • #283589

    #283589

    oklch(37.3% 0.14 271.2)

  • #603400

    #603400

    oklch(37.3% 0.086 61.8)

  • #3A4700

    #3A4700

    oklch(37.3% 0.089 120.8)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #283589

    #283589

    oklch(37.3% 0.14 271.2)

  • #7A1104

    #7A1104

    oklch(37.3% 0.14 31.1)

  • #004F23

    #004F23

    oklch(37.4% 0.1 151.1)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #283589

    #283589

    oklch(37.3% 0.14 271.2)

  • #760D3C

    #760D3C

    oklch(37.3% 0.14 1.1)

  • #503E00

    #503E00

    oklch(37.3% 0.076 90.1)

  • #004C43

    #004C43

    oklch(37.4% 0.067 181.5)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #283589, closest first.

Similar named colors

The eight closest entries in our named color list, with their ΔE distance.

Use #283589 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.