Palettes / Colors / #666EEB

#666EEB — Light Blue

#666EEB is a blue color we call Light Blue, closest to the named color SlateBlue (#6A5ACD). It belongs to the blue family.

Color name

Closest CSS keyword: slateblue (#6A5ACD) — not an exact match. CSS slateblue gives you #6A5ACD, a different color; use #666EEB when you need this exact shade.

Sources: common names follow widely used color-name references; CSS keywords and their hex values follow the CSS Color specification.

#666EEB is a cool blue color associated with trust, calm and professionalism. It is saturated enough to be the accent — buttons, highlights and calls to action — while neutrals do the quiet work around it.

Its strongest partner is its complement #EBE266; it also sits naturally between #66B1EB and #9F66EB. In the palettes below you can see it working alongside real color combinations from our collection.

Copy HEX Copy RGB Copy HSL Download PNG swatch SVG

Color values

RGB & CMYK percentages

Red 40% · Green 43% · Blue 92%

Cyan 57% · Magenta 53% · Yellow 0% · Key 8%

CMYK values are unprofiled approximations for screen reference — not a print-proofing guarantee.

Previews

CSS code for #666EEB

.text { color: #666EEB; }
.background { background-color: #666EEB; }
.border { border: 3px solid #666EEB; }
.text-rgb { color: rgb(102, 110, 235); }
.text-hsl { color: hsl(236, 77%, 66%); }
.text-shadow-hex { text-shadow: 4px 4px 2px #666EEB; }
.text-shadow-rgba { text-shadow: 4px 4px 2px rgba(102, 110, 235, 0.8); }
.box-shadow-hex { box-shadow: 1px 1px 3px 2px #666EEB; }
.box-shadow-rgba { box-shadow: 1px 1px 3px 2px rgba(102, 110, 235, 0.8); }

HTML: <p style="color:#666EEB">Text here</p> · <div style="background-color:#666EEB">Div content here</div>

Shades of #666EEB

Tints of #666EEB

Tones of #666EEB

Color harmonies

Complementary — #EBE266:

Analogous:

Triadic:

Contrast & accessibility

Best text color on #666EEB: #000000.

Semi-transparent (opacity) text on #666EEB

Text set with opacity blends into the background, so its real contrast is lower than the solid ratios above. Choose a text color and an opacity to see the blended color and its true ratio:

How #666EEB looks with color blindness

Simulated with standard Machado color-vision-deficiency matrices — useful when this color carries meaning in charts, maps or interfaces:

Closest design-system colors

The nearest matches in the Tailwind CSS, Material Design and Bootstrap palettes — handy when you need a framework class instead of a raw hex:

Palettes with a similar color

These palettes use a close neighbour of #666EEB rather than the exact color:

Similar colors

The closest colors that actually appear in our palette collection — click any to open its page:

Browse neighbouring colors

← #666EEA  ·  #666EEC →

Frequently asked questions

What color is #666EEB?

#666EEB is Light Blue, a blue color (RGB 102, 110, 235). Its closest standard named color is SlateBlue.

What is the RGB and HSL of #666EEB?

#666EEB is RGB 102, 110, 235 — HSL 236°, 77%, 66% — CMYK 57%, 53%, 0%, 8%.

What colors go with #666EEB?

Its complement is #EBE266; analogous partners are #66B1EB and #9F66EB. It also appears in 6+ palettes in our collection.

Can I use #666EEB for text?

Black text on #666EEB has a contrast ratio of 4.99:1 (passes WCAG AA); white text gives 4.20:1.