Accessibility
Vs white / black
6.61:1 · 3.18:1
Sources
Codes
HEX
#0040ff
RGB
rgb(0, 64, 255)
RGBA
rgba(0, 64, 255, 1)
HSL
hsl(225, 100%, 50%)
HSLA
hsla(225, 100%, 50%, 1)
HSV
hsv(225, 100%, 100%)
LAB
lab(39.38% 58.06 -96.05)
LCH
lch(39.38% 112.23 301.15)
OKLAB
oklab(0.5011 -0.0302 -0.2787)
OKLCH
oklch(0.5011 0.2803 263.82)
XYZ
xyz(19.88, 10.88, 95.64)
CMYK
cmyk(100%, 75%, 0%, 0%)
CSS
color: #0040ff;
CSS variable
--color-0040ff: #0040ff;
SCSS
$color-0040ff: #0040ff;
JavaScript
const color = "#0040ff";
TypeScript
const color: string = "#0040ff";
React
style={{ backgroundColor: "#0040ff" }}
JSON
{ "hex": "#0040ff", "rgb": { "r": 0, "g": 64, "b": 255 }, "oklch": "oklch(0.5011 0.2803 263.82)" }
Export
:root {
--#0040ff-1: #0040ff;
}Design systems
An arbitrary HEX is not an official Tailwind, Material, or Bootstrap color. Distance is CIEDE2000.
Nearest Tailwind color
indigo-600
Noticeably different · ΔE 4.17 · #4F46E5
Nearest CSS named color
Blue
Very different · ΔE 8.14 · #0000FF
Nearest Material color
indigo-500
Very different · ΔE 9.58 · #3F51B5
Nearest Bootstrap color
primary
Very different · ΔE 13.72 · #0D6EFD
OKLCH
Generated in OKLCH from this hex. Not an official Tailwind scale unless the hex itself is a Tailwind token.
Palette
Full scale from light tints through the base color into deep shades
Palette
Mixed toward white — soft backgrounds and highlights
Palette
Mixed toward black — depth, text, and emphasis
Palette
Mixed toward neutral grey — muted UI surfaces
Harmony
Opposite on the color wheel for contrast
Harmony
Neighbors that sit comfortably together
Harmony
Evenly spaced triad for vibrant sets
Harmony
Base plus two accents beside the complement
Harmony
Same hue, varied lightness and saturation
Using this color
#0040FF (#0040ff) sits in the blue family at about 225° hue, 100% saturation, and 50% lightness. Contrast is 6.61:1 on white and 3.18:1 on black, so white labels read more clearly on the swatch itself. Nearest Tailwind token: indigo-600 (approximation unless the hex is an official scale stop).
Sensible jobs for this swatch
On a black or near-black UI, #0040ff is 3.18:1. Prefer it as a fill, border, or large heading rather than 16px copy.
High chroma can vibrate against complementary hues. If a pairing feels noisy, drop saturation on the background rather than the brand accent.
Family context: Trust, calm, and professionalism. The most used color in SaaS, finance, and healthcare. Common uses still include buttons, charts, and accents in the Blue range — always verify the pair for this exact hex in the contrast checker.
Related
Nearby colors from the library by perceptual distance