Palettes / Colors / #155BBB

#155BBB — Vivid Blue

#155BBB is a blue color we call Vivid Blue, closest to the named color RoyalBlue (#4169E1). It belongs to the blue family.

Color name

Closest CSS keyword: royalblue (#4169E1) — not an exact match. CSS royalblue gives you #4169E1, a different color; use #155BBB 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.

#155BBB 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 #BC7615; it also sits naturally between #15AEBC and #2315BC. In the palettes below you can see it working alongside real color combinations from our collection.

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Color values

RGB & CMYK percentages

Red 8% · Green 36% · Blue 73%

Cyan 89% · Magenta 51% · Yellow 0% · Key 27%

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

Previews

CSS code for #155BBB

.text { color: #155BBB; }
.background { background-color: #155BBB; }
.border { border: 3px solid #155BBB; }
.text-rgb { color: rgb(21, 91, 187); }
.text-hsl { color: hsl(215, 80%, 41%); }
.text-shadow-hex { text-shadow: 4px 4px 2px #155BBB; }
.text-shadow-rgba { text-shadow: 4px 4px 2px rgba(21, 91, 187, 0.8); }
.box-shadow-hex { box-shadow: 1px 1px 3px 2px #155BBB; }
.box-shadow-rgba { box-shadow: 1px 1px 3px 2px rgba(21, 91, 187, 0.8); }

HTML: <p style="color:#155BBB">Text here</p> · <div style="background-color:#155BBB">Div content here</div>

Shades of #155BBB

Tints of #155BBB

Tones of #155BBB

Color harmonies

Complementary — #BC7615:

Analogous:

Triadic:

Contrast & accessibility

Best text color on #155BBB: #FFFFFF.

Semi-transparent (opacity) text on #155BBB

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 #155BBB 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 #155BBB 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

← #155BBA  ·  #155BBC →

Frequently asked questions

What color is #155BBB?

#155BBB is Vivid Blue, a blue color (RGB 21, 91, 187). Its closest standard named color is RoyalBlue.

What is the RGB and HSL of #155BBB?

#155BBB is RGB 21, 91, 187 — HSL 215°, 80%, 41% — CMYK 89%, 51%, 0%, 27%.

What colors go with #155BBB?

Its complement is #BC7615; analogous partners are #15AEBC and #2315BC. It also appears in 6+ palettes in our collection.

Can I use #155BBB for text?

White text on #155BBB has a contrast ratio of 6.47:1 (passes WCAG AA); black text gives 3.25:1.