#284D9F

Closest named color: Cobalt (#1E488F). oklch(44.1% 0.14 263.5), rgb(40, 77, 159).

Aa

White text reads best on this color (7.91:1).

About this color

#284D9F is a dark, vivid blue. In OKLCH its lightness is 44%, its chroma 0.140 and its hue 263°. Its hue sits on the cool side of the wheel. The nearest named color is Cobalt (#1E488F), ΔE 0.031 away. White text reads best on it, at 7.91:1.

Hue familyBlues
Lightnessdark (44%)
Chromavivid (0.140)
Temperaturecool
Nearest nameCobalt (#1E488F)
Black text2.65:1
White text7.91:1

Values

HEX#284D9F
RGBrgb(40, 77, 159)
HSLhsl(221, 60%, 39%)
OKLCHoklch(44.1% 0.14 263.5)

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 #284D9F 7.91:1 AAA Lc -91.8 Preferred for body text
Black text on #284D9F 2.65:1 Fails Lc 16.9 Dividers and decoration only
#284D9F text on white 7.91:1 AAA Lc 87.1 Fine for body text
#284D9F text on black 2.65:1 Fails Lc -15.0 Dividers and decoration only

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.

  1. Step 50

    50

    #F2F6FD

    oklch(97.2% 0.01 261.8)

  2. Step 100

    100

    #E2EAFA

    oklch(93.6% 0.023 264.5)

  3. Step 200

    200

    #CADAF8

    oklch(88.6% 0.045 263.1)

  4. Step 300

    300

    #A5C1F6

    oklch(80.9% 0.081 263)

  5. Step 400

    400

    #769FF2

    oklch(70.8% 0.13 263.4)

  6. Step 500

    500

    #5384EE

    oklch(63.1% 0.168 263.6)

  7. Step 600

    600

    #386BDC

    oklch(55.6% 0.182 263.4)

  8. Step 700

    700

    #2B58BF

    oklch(49.1% 0.17 263.6)

  9. Step 800

    800 (this color)

    #284D9F

    oklch(44.1% 0.14 263.5)

  10. Step 900

    900

    #223E7B

    oklch(37.8% 0.109 263.5)

  11. Step 950

    950

    #142548

    oklch(27.1% 0.069 263.1)

Export this scale for Tailwind in the Tailwind colors tool

#284D9F 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)#1A57A20.027
Deuteranopia (no green cones)#004C9D0.024
Tritanopia (no blue cones)#00616E0.112
Achromatopsia (no color)#5151510.140

Harmonies

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

Complementary

The opposite hue (180°).

  • #284D9F

    #284D9F

    oklch(44.1% 0.14 263.5)

  • #6B4D00

    #6B4D00

    oklch(44.1% 0.091 82.7)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #284D9F

    #284D9F

    oklch(44.1% 0.14 263.5)

  • #005A7D

    #005A7D

    oklch(44% 0.092 233.6)

  • #593E97

    #593E97

    oklch(44.1% 0.14 293.9)

Open the analogous palette in the generator

Split complementary

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

  • #284D9F

    #284D9F

    oklch(44.1% 0.14 263.5)

  • #803E00

    #803E00

    oklch(44.1% 0.111 53.8)

  • #535800

    #535800

    oklch(44.1% 0.099 113.5)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #284D9F

    #284D9F

    oklch(44.1% 0.14 263.5)

  • #90282B

    #90282B

    oklch(44.1% 0.139 23.5)

  • #0A6511

    #0A6511

    oklch(44.1% 0.14 143.4)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #284D9F

    #284D9F

    oklch(44.1% 0.14 263.5)

  • #892859

    #892859

    oklch(44.1% 0.14 353.3)

  • #6B4D00

    #6B4D00

    oklch(44.1% 0.091 82.7)

  • #00624F

    #00624F

    oklch(44.2% 0.085 173.4)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #284D9F, closest first.

Similar named colors

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

Use #284D9F 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.