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#175758

a deep, vivid cyan · cool · closest name: Dark Slate Gray

RGB
23, 87, 88
HSL
181°, 59%, 22%
CMYK
74, 1, 0, 66
Luminance
0.0770

At a glance

Every number on this page in one read: what #175758 is made of, how bright it looks, and which way it leans.

Hex
#175758
Hue
181°
cyan
Saturation
59%
vivid
Lightness
22%
deep
Brightness
35%
HSV value
Perceived
29%
weighted brightness
Luminance
0.0770
WCAG relative
Temperature
Cool
88/100 cool
Color family
Cyan
Tone
Vivid
Best ink
White
8.27:1
Closest name
Dark Slate Gray
ΔE2000 5.6
Where it sits
Hue181° of 360°
Saturation59%
Lightness22%
Temperature
Warm ← → Cool88% 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#175758
RGBrgb(23, 87, 88)
HSLhsl(181, 59%, 22%)
CMYKcmyk(74%, 1%, 0%, 66%)
LABlab(33.4 -19.1 -6.4)
LCHlch(33.4 20.1 198.5)
OKLCHoklch(0.418 0.062 196.6)
Decimal1529688
Display P3color(display-p3 0.090 0.341 0.345)

Copy-ready code

/* CSS */
color: #175758;
background-color: #175758;
/* Tailwind (arbitrary) */
class="text-[#175758] bg-[#175758]"
/* SCSS */
$brand: #175758;
/* SwiftUI */
Color(red: 0.090, green: 0.341, blue: 0.345)
/* Android */
Color.parseColor("#175758")
/* Flutter */
Color(0xFF175758)
/* Python / OpenCV (BGR) */
(88, 87, 23)

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 #175758 · 8.27:1
Use #ffffffAAA at every size.
Aa
White text · 8.27:1 · recommended
AA pass · AA large pass · AAA pass
Aa
Black text · 2.54:1
AA fail · AA large fail · AAA fail
Reading the other direction: #175758 as text scores 8.27:1 on white and 2.54:1 on black.

Accessibility — WCAG contrast

Aa
#175758 on white: 8.27:1
AA ✓ pass · AA-large · AAA
Aa
#175758 on black: 2.54:1
AA ✗ fail · AA-large · AAA
true color
protanopia · #515358
deuteranopia · #474B58
tritanopia · #005A57

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #175758 is pinned to step 900; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F4FBFB
#E9F6F7
#CDEEEF
#A6E7E8
#7ADBDC
#4DCFD1
#33C0C2
#2AA0A2
#228081
#175758
#123A3B
Base = 900Lightest = 50 · #F4FBFBDarkest = 950 · #123A3B
:root {
  --brand-50: #F4FBFB;
  --brand-100: #E9F6F7;
  --brand-200: #CDEEEF;
  --brand-300: #A6E7E8;
  --brand-400: #7ADBDC;
  --brand-500: #4DCFD1;
  --brand-600: #33C0C2;
  --brand-700: #2AA0A2;
  --brand-800: #228081;
  --brand-900: #175758;
  --brand-950: #123A3B;
  --brand: #175758;
  --brand-ink: #ffffff;
}

Colors that work with #175758

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#F4FAFA
Tinted page background
Border#C0ECED
Hairlines and dividers
Muted text#4B9A9B
Captions on the surface
Accent#5A1525
Second voice, not a rival
Dark variant#1A6465
Hover, pressed, headers
Light variant#EBF9FA
Selected rows, tints
Dark surface#142424
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 #175758

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
  • Thin strokes and 1px borders — they disappear on light UI
  • 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#581817
Analogous left#175839
Analogous right#173758
Split-complement 1#581737
Split-complement 2#583917
Triadic 1#581757
Triadic 2#575817
Tetradic#391758

RGB percentages

Red9.0%
Green34.1%
Blue34.5%

CMYK percentages

Cyan73.9%
Magenta1.1%
Yellow0.0%
Key (black)65.5%

Color previews

#175758 text on a black background

contrast 2.54:1

Card sample

#175758 text on a white background

contrast 8.27:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #175758;
Background color
Panel with #175758 background
background-color: #175758;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #175758;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(23, 87, 88, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(23, 87, 88, 0.45);
Border & gradient
Gradient panel
border: 3px solid #175758;
background: linear-gradient(135deg, #175758, #172C58);

Monochromatic scale

Palettes built from #175758

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.

#175758 in the real world

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

Industries
TechnologyTravelHealthcareMedia
Common UI roles
ButtonsLinksFocus statesCharts
Print note

Converts to four-color process without much drama. Proof it anyway.

#175758, answered

What color is #175758?

#175758 is a deep vivid cyan, closest to Dark Slate Gray (ΔE2000 5.6). It sits at 181° on the hue wheel with 59% saturation and 22% lightness, which reads as cool.

What is the RGB value of #175758?

rgb(23, 87, 88) — 23 red, 87 green and 88 blue out of 255, or 9% / 34.1% / 34.5% by channel.

Is #175758 a light or a dark color?

It is a dark color. Relative luminance is 0.0770 and perceived brightness is 29%, so white text on it reaches 8.27:1.

Should I use black or white text on #175758?

White. It scores 8.27:1 against #175758, versus 2.54:1 for black — AAA at any size.

What is the complementary color of #175758?

#581817 sits directly opposite on the wheel. Softer options are the split-complements #581737 and #583917, which give the same contrast with far less vibration.

What colors go well with #175758?

For interface work: #F4FAFA as the surface, #C0ECED for borders, #4B9A9B for secondary text, #5A1525 as an accent and #1A6465 for hover and pressed states. For a palette, the analogous pair #175839 and #173758 stays calm, while #581817 is the loudest partner.

What is #175758 in CMYK for printing?

cmyk(74%, 1%, 0%, 66%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #175758 warm or cool?

Cool — it scores 88 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #175841; nudged cooler, #164059.

Work with #175758 in the Color Lab