#218DBC

Closest named color: Blue NCS (#118AB2). oklch(60.7% 0.116 233), rgb(33, 141, 188).

Aa

Black text reads best on this color (5.60:1).

About this color

#218DBC is a medium-dark, moderately saturated blue. In OKLCH its lightness is 61%, its chroma 0.116 and its hue 233°. Its hue sits on the cool side of the wheel. The nearest named color is Blue NCS (#118AB2), ΔE 0.018 away. Black text reads best on it, at 5.60:1.

Hue familyBlues
Lightnessmedium-dark (61%)
Chromamoderately saturated (0.116)
Temperaturecool
Nearest nameBlue NCS (#118AB2)
Black text5.60:1
White text3.74:1

Values

HEX#218DBC
RGBrgb(33, 141, 188)
HSLhsl(198, 70%, 43%)
OKLCHoklch(60.7% 0.116 233)

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 #218DBC 3.74:1 AA large text Lc -70.1 Content text, not long reading
Black text on #218DBC 5.60:1 AA Lc 39.5 Non-text elements, placeholder text
#218DBC text on white 3.74:1 AA large text Lc 64.6 Content text, not long reading
#218DBC text on black 5.60:1 AA Lc -37.1 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

    #9DC8E0

    oklch(81% 0.057 232.8)

  5. Step 400

    400

    #63AAD0

    oklch(70.6% 0.091 233.5)

  6. Step 500

    500 (this color)

    #218DBC

    oklch(60.7% 0.116 233)

  7. Step 600

    600

    #007DAB

    oklch(55.5% 0.115 233.2)

  8. Step 700

    700

    #006991

    oklch(49% 0.102 233.6)

  9. Step 800

    800

    #005677

    oklch(42.6% 0.088 233.1)

  10. Step 900

    900

    #054863

    oklch(37.8% 0.075 232.7)

  11. Step 950

    950

    #082A3A

    oklch(27% 0.048 233.3)

Export this scale for Tailwind in the Tailwind colors tool

#218DBC 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)#768CBE0.074
Deuteranopia (no green cones)#617EBB0.061
Tritanopia (no blue cones)#009A9D0.070
Achromatopsia (no color)#8484840.116

Harmonies

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

Complementary

The opposite hue (180°).

  • #218DBC

    #218DBC

    oklch(60.7% 0.116 233)

  • #B86D3A

    #B86D3A

    oklch(60.8% 0.116 52.9)

Open the complementary palette in the generator

Analogous

Neighbouring hues, 30° either side.

  • #218DBC

    #218DBC

    oklch(60.7% 0.116 233)

  • #00949E

    #00949E

    oklch(60.7% 0.103 203.2)

  • #5D81C8

    #5D81C8

    oklch(60.8% 0.116 263)

Open the analogous palette in the generator

Split complementary

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

  • #218DBC

    #218DBC

    oklch(60.7% 0.116 233)

  • #BE6461

    #BE6461

    oklch(60.7% 0.116 23.1)

  • #A47B1C

    #A47B1C

    oklch(60.8% 0.116 83)

Open the split complementary palette in the generator

Triadic

Three hues spaced 120° apart.

  • #218DBC

    #218DBC

    oklch(60.7% 0.116 233)

  • #B76388

    #B76388

    oklch(60.7% 0.116 353.3)

  • #83892B

    #83892B

    oklch(60.7% 0.116 112.9)

Open the triadic palette in the generator

Square

Four hues spaced 90° apart.

  • #218DBC

    #218DBC

    oklch(60.7% 0.116 233)

  • #A369AA

    #A369AA

    oklch(60.6% 0.116 323)

  • #B86D3A

    #B86D3A

    oklch(60.8% 0.116 52.9)

  • #559452

    #559452

    oklch(60.7% 0.117 143)

Open the square palette in the generator

Palettes with this color

Curated palettes that contain a color within ΔE 0.04 (OKLab) of #218DBC, closest first.

Similar named colors

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

Use #218DBC 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.