#288BBA

Closest named color: Blue NCS (#118AB2). oklch(60.3% 0.113 234.3), rgb(40, 139, 186).

Aa

Black text reads best on this color (5.49:1).

About this color

#288BBA is a medium-dark, moderately saturated blue. In OKLCH its lightness is 60%, its chroma 0.113 and its hue 234°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.016 away. Black text reads best on it, at 5.49:1.

Hue familyBlues
Lightnessmedium-dark (60%)
Chromamoderately saturated (0.113)
Temperaturecool
Nearest nameBlue NCS (#118AB2)
Black text5.49:1
White text3.82:1

Values

HEX#288BBA
RGBrgb(40, 139, 186)
HSLhsl(199, 65%, 44%)
OKLCHoklch(60.3% 0.113 234.3)

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 #288BBA 3.82:1 AA large text Lc -70.9 Content text, not long reading
Black text on #288BBA 5.49:1 AA Lc 38.7 Non-text elements, placeholder text
#288BBA text on white 3.82:1 AA large text Lc 65.4 Content text, not long reading
#288BBA text on black 5.49:1 AA Lc -36.3 Non-text elements, placeholder text

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 500.

  1. Step 50

    50

    #F1F6FA

    oklch(97.1% 0.008 241.7)

  2. Step 100

    100

    #E0ECF3

    oklch(93.6% 0.016 233)

  3. Step 200

    200

    #C6DDEB

    oklch(88.5% 0.031 234.5)

  4. Step 300

    300

    #9EC7DF

    oklch(80.8% 0.055 234)

  5. Step 400

    400

    #66AAD0

    oklch(70.8% 0.089 234.4)

  6. Step 500

    500 (this color)

    #288BBA

    oklch(60.3% 0.113 234.3)

  7. Step 600

    600

    #007DAD

    oklch(55.6% 0.117 234.3)

  8. Step 700

    700

    #006992

    oklch(49.1% 0.103 234.3)

  9. Step 800

    800

    #005678

    oklch(42.7% 0.089 233.9)

  10. Step 900

    900

    #0B4763

    oklch(37.6% 0.074 235.1)

  11. Step 950

    950

    #0A2A3A

    oklch(27% 0.047 234.3)

Export this scale for Tailwind in the Tailwind colors tool

#288BBA 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)#748ABC0.070
Deuteranopia (no green cones)#607CB90.058
Tritanopia (no blue cones)#00979B0.069
Achromatopsia (no color)#8282820.113

Harmonies

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

Complementary

The opposite hue (180°).

  • #288BBA

    #288BBA

    oklch(60.3% 0.113 234.3)

  • #B46D39

    #B46D39

    oklch(60.3% 0.113 54.8)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #288BBA

    #288BBA

    oklch(60.3% 0.113 234.3)

  • #00929D

    #00929D

    oklch(60.2% 0.103 204.2)

  • #5F7FC4

    #5F7FC4

    oklch(60.3% 0.112 264.4)

Open the analogous palette in the generator

Split complementary

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

  • #288BBA

    #288BBA

    oklch(60.3% 0.113 234.3)

  • #BB645F

    #BB645F

    oklch(60.3% 0.113 24.4)

  • #A07A1F

    #A07A1F

    oklch(60.1% 0.113 84.2)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #288BBA

    #288BBA

    oklch(60.3% 0.113 234.3)

  • #B56385

    #B56385

    oklch(60.4% 0.113 354.7)

  • #80882F

    #80882F

    oklch(60.2% 0.112 114.2)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #288BBA

    #288BBA

    oklch(60.3% 0.113 234.3)

  • #A268A7

    #A268A7

    oklch(60.2% 0.114 324.1)

  • #B46D39

    #B46D39

    oklch(60.3% 0.113 54.8)

  • #539254

    #539254

    oklch(60.1% 0.113 144.3)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #288BBA, closest first.

Similar named colors

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

Use #288BBA 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.