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#115d8b

a dark, electric blue · cool · closest name: Royal Blue

RGB
17, 93, 139
HSL
203°, 78%, 31%
CMYK
88, 33, 0, 46
Luminance
0.0981

At a glance

Every number on this page in one read: what #115d8b is made of, how bright it looks, and which way it leans.

Hex
#115d8b
Hue
203°
blue
Saturation
78%
electric
Lightness
31%
dark
Brightness
55%
HSV value
Perceived
34%
weighted brightness
Luminance
0.0981
WCAG relative
Temperature
Cool
97/100 cool
Color family
Blue
Tone
Electric
Best ink
White
7.09:1
Closest name
Royal Blue
ΔE2000 13.4
Where it sits
Hue203° of 360°
Saturation78%
Lightness31%
Temperature
Warm ← → Cool97% cool

Reads cool. Warm and cool siblings keep the same lightness, so you can swap one in without redoing your contrast maths.

Every format

HEX#115d8b
RGBrgb(17, 93, 139)
HSLhsl(203, 78%, 31%)
CMYKcmyk(88%, 33%, 0%, 46%)
LABlab(37.5 -4.4 -31.6)
LCHlch(37.5 31.9 262.1)
OKLCHoklch(0.459 0.102 242.1)
Decimal1138059
Display P3color(display-p3 0.067 0.365 0.545)

Copy-ready code

/* CSS */
color: #115d8b;
background-color: #115d8b;
/* Tailwind (arbitrary) */
class="text-[#115d8b] bg-[#115d8b]"
/* SCSS */
$brand: #115d8b;
/* SwiftUI */
Color(red: 0.067, green: 0.365, blue: 0.545)
/* Android */
Color.parseColor("#115d8b")
/* Flutter */
Color(0xFF115D8B)
/* Python / OpenCV (BGR) */
(139, 93, 17)

Best text color

Only one of black and white can be right. This is the one, with the number that proves it.

Readable at a glance#ffffff on #115d8b · 7.09:1
Use #ffffffAAA at every size.
Aa
White text · 7.09:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 2.96:1
AA fail · AA large fail · AAA fail
Reading the other direction: #115d8b as text scores 7.09:1 on white and 2.96:1 on black.

Accessibility — WCAG contrast

Aa
#115d8b on white: 7.09:1
AA ✓ pass · AA-large · AAA
Aa
#115d8b on black: 2.96:1
AA ✗ fail · AA-large · AAA
true color
protanopia · #475E8D
deuteranopia · #36538A
tritanopia · #00686D

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #115d8b is pinned to step 800; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F3F9FC
#E6F2F9
#C7E3F5
#9BD2F3
#69BBED
#37A4E7
#1B92DA
#167AB6
#115d8b
#114869
#0B2D42
Base = 800Lightest = 50 · #F3F9FCDarkest = 950 · #0B2D42
:root {
  --brand-50: #F3F9FC;
  --brand-100: #E6F2F9;
  --brand-200: #C7E3F5;
  --brand-300: #9BD2F3;
  --brand-400: #69BBED;
  --brand-500: #37A4E7;
  --brand-600: #1B92DA;
  --brand-700: #167AB6;
  --brand-800: #115d8b;
  --brand-900: #114869;
  --brand-950: #0B2D42;
  --brand: #115d8b;
  --brand-ink: #ffffff;
}

Colors that work with #115d8b

Not a palette — a role sheet. Each swatch answers one question you will hit while building the component.

Text on it#ffffff
White wins here
Surface#F4F8FA
Tinted page background
Border#C0DCED
Hairlines and dividers
Muted text#4B7D9B
Captions on the surface
Accent#8E1E0E
Second voice, not a rival
Dark variant#0E4C72
Hover, pressed, headers
Light variant#E8F5FC
Selected rows, tints
Dark surface#141E24
Dark-mode background
Light mode
Everything in its place

Surface, border, heading and body all derive from this one hue, so the screen stays coherent without a second palette.

Primary actionSecondaryBadge
Dark mode
Same hue, inverted

Lightness flips, hue holds. The accent stays the anchor in both themes.

Primary actionSecondaryAccent

How to use #115d8b

Derived from its contrast, chroma and lightness — not from taste.

Works well for
  • Body text and links on white
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Headers, footers and dark-mode surfaces
  • Brand accents, badges and data highlights
Use with care
  • Text on black or near-black surfaces
  • Full-page backgrounds — tiring over long sessions
  • Black text placed on it
  • Pairing with a same-lightness hue — edges vibrate

Similar colors

One move away from this hex in each direction. Every swatch is its own page.

Color relationships

The wheel positions with their names attached, so you can grab the one you actually need.

Complementary#8B3F11
Analogous left#118B7C
Analogous right#11208B
Split-complement 1#8B1120
Split-complement 2#8B7C11
Triadic 1#8B115D
Triadic 2#5D8B11
Tetradic#7C118B

RGB percentages

Red6.7%
Green36.5%
Blue54.5%

CMYK percentages

Cyan87.8%
Magenta33.1%
Yellow0.0%
Key (black)45.5%

Color previews

#115d8b text on a black background

contrast 2.96:1

Card sample

#115d8b text on a white background

contrast 7.09:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #115d8b;
Background color
Panel with #115d8b background
background-color: #115d8b;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #115d8b;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(17, 93, 139, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(17, 93, 139, 0.45);
Border & gradient
Gradient panel
border: 3px solid #115d8b;
background: linear-gradient(135deg, #115d8b, #16118B);

Monochromatic scale

Palettes built from #115d8b

Shades — darker

Tints — lighter

Color harmonies

Nearest named colors

Ranked with CIEDE2000 across all 139 CSS keywords. Under ΔE 2 the eye stops telling them apart; over ΔE 10 they are plainly different colors.

#115d8b in the real world

Where a color in this family tends to land, and the interface roles it is usually asked to play.

Industries
TechnologyFinanceHealthcareEnterprise SaaS
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Sits outside most CMYK gamuts — expect a duller press result, or specify a spot ink.

#115d8b, answered

What color is #115d8b?

#115d8b is a dark electric blue, closest to Royal Blue (ΔE2000 13.4). It sits at 203° on the hue wheel with 78% saturation and 31% lightness, which reads as cool.

What is the RGB value of #115d8b?

rgb(17, 93, 139) — 17 red, 93 green and 139 blue out of 255, or 6.7% / 36.5% / 54.5% by channel.

Is #115d8b a light or a dark color?

It is a dark color. Relative luminance is 0.0981 and perceived brightness is 34%, so white text on it reaches 7.09:1.

Should I use black or white text on #115d8b?

White. It scores 7.09:1 against #115d8b, versus 2.96:1 for black — AAA at any size.

What is the complementary color of #115d8b?

#8B3F11 sits directly opposite on the wheel. Softer options are the split-complements #8B1120 and #8B7C11, which give the same contrast with far less vibration.

What colors go well with #115d8b?

For interface work: #F4F8FA as the surface, #C0DCED for borders, #4B7D9B for secondary text, #8E1E0E as an accent and #0E4C72 for hover and pressed states. For a palette, the analogous pair #118B7C and #11208B stays calm, while #8B3F11 is the loudest partner.

What is #115d8b in CMYK for printing?

cmyk(88%, 33%, 0%, 46%). This is a screen-to-ink approximation — a color this saturated sits outside most CMYK gamuts and will print duller than it looks here.

Is #115d8b warm or cool?

Cool — it scores 97 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #118A8B; nudged cooler, #0D4476.

Work with #115d8b in the Color Lab