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#40cedf

a balanced, vivid cyan · cool · closest name: Dark Turquoise

RGB
64, 206, 223
HSL
186°, 71%, 56%
CMYK
71, 8, 0, 13
Luminance
0.5056

At a glance

Every number on this page in one read: what #40cedf is made of, how bright it looks, and which way it leans.

Hex
#40cedf
Hue
186°
cyan
Saturation
71%
vivid
Lightness
56%
balanced
Brightness
87%
HSV value
Perceived
70%
weighted brightness
Luminance
0.5056
WCAG relative
Temperature
Cool
90/100 cool
Color family
Cyan
Tone
Vivid
Best ink
Black
11.11:1
Closest name
Dark Turquoise
ΔE2000 5.7
Where it sits
Hue186° of 360°
Saturation71%
Lightness56%
Temperature
Warm ← → Cool90% 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#40cedf
RGBrgb(64, 206, 223)
HSLhsl(186, 71%, 56%)
CMYKcmyk(71%, 8%, 0%, 13%)
LABlab(76.4 -31.6 -19.3)
LCHlch(76.4 37.0 211.4)
OKLCHoklch(0.784 0.119 206.8)
Decimal4247263
Display P3color(display-p3 0.251 0.808 0.875)

Copy-ready code

/* CSS */
color: #40cedf;
background-color: #40cedf;
/* Tailwind (arbitrary) */
class="text-[#40cedf] bg-[#40cedf]"
/* SCSS */
$brand: #40cedf;
/* SwiftUI */
Color(red: 0.251, green: 0.808, blue: 0.875)
/* Android */
Color.parseColor("#40cedf")
/* Flutter */
Color(0xFF40CEDF)
/* Python / OpenCV (BGR) */
(223, 206, 64)

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#000000 on #40cedf · 11.11:1
Use #000000AAA at every size.
Aa
White text · 1.89:1
AA fail · AA large fail · AAA fail
Aa
Black text · 11.11:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #40cedf as text scores 1.89:1 on white and 11.11:1 on black.

Accessibility — WCAG contrast

Aa
#40cedf on white: 1.89:1
AA ✗ fail · AA-large · AAA
Aa
#40cedf on black: 11.11:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #BDC6E0
deuteranopia · #A6B5DF
tritanopia · #00D7D3

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #40cedf is pinned to step 500; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#F3FBFC
#E7F6F8
#C9EEF3
#9FE6EF
#6FDAE7
#40cedf
#23BFD2
#1D9FAF
#177F8C
#155D65
#0D3A3F
Base = 500Lightest = 50 · #F3FBFCDarkest = 950 · #0D3A3F
:root {
  --brand-50: #F3FBFC;
  --brand-100: #E7F6F8;
  --brand-200: #C9EEF3;
  --brand-300: #9FE6EF;
  --brand-400: #6FDAE7;
  --brand-500: #40cedf;
  --brand-600: #23BFD2;
  --brand-700: #1D9FAF;
  --brand-800: #177F8C;
  --brand-900: #155D65;
  --brand-950: #0D3A3F;
  --brand: #40cedf;
  --brand-ink: #000000;
}

Colors that work with #40cedf

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

Text on it#000000
Black wins here
Surface#F4FAFA
Tinted page background
Border#C0E8ED
Hairlines and dividers
Muted text#4B929B
Captions on the surface
Accent#E33C54
Second voice, not a rival
Dark variant#12646D
Hover, pressed, headers
Light variant#E9F9FB
Selected rows, tints
Dark surface#142324
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 #40cedf

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

Works well for
  • Text and icons on dark surfaces
  • Primary buttons and calls to action
  • Focus rings, active and selected states
  • Brand accents, badges and data highlights
Use with care
  • Text of any size on white — fails WCAG AA
  • Full-page backgrounds — tiring over long sessions
  • 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#DF5140
Analogous left#40DFA1
Analogous right#407FDF
Split-complement 1#DF407F
Split-complement 2#DFA140
Triadic 1#DF40CE
Triadic 2#CEDF40
Tetradic#A140DF

RGB percentages

Red25.1%
Green80.8%
Blue87.5%

CMYK percentages

Cyan71.3%
Magenta7.6%
Yellow0.0%
Key (black)12.5%

Color previews

#40cedf text on a black background

contrast 11.11:1

Card sample

#40cedf text on a white background

contrast 1.89:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #40cedf;
Background color
Panel with #40cedf background
background-color: #40cedf;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #40cedf;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(64, 206, 223, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(64, 206, 223, 0.45);
Border & gradient
Gradient panel
border: 3px solid #40cedf;
background: linear-gradient(135deg, #40cedf, #4064DF);

Monochromatic scale

Palettes built from #40cedf

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.

#40cedf 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.

#40cedf, answered

What color is #40cedf?

#40cedf is a balanced vivid cyan, closest to Dark Turquoise (ΔE2000 5.7). It sits at 186° on the hue wheel with 71% saturation and 56% lightness, which reads as cool.

What is the RGB value of #40cedf?

rgb(64, 206, 223) — 64 red, 206 green and 223 blue out of 255, or 25.1% / 80.8% / 87.5% by channel.

Is #40cedf a light or a dark color?

It is a light color. Relative luminance is 0.5056 and perceived brightness is 70%, so black text on it reaches 11.11:1.

Should I use black or white text on #40cedf?

Black. It scores 11.11:1 against #40cedf, versus 1.89:1 for white — AAA at any size.

What is the complementary color of #40cedf?

#DF5140 sits directly opposite on the wheel. Softer options are the split-complements #DF407F and #DFA140, which give the same contrast with far less vibration.

What colors go well with #40cedf?

For interface work: #F4FAFA as the surface, #C0E8ED for borders, #4B929B for secondary text, #E33C54 as an accent and #12646D for hover and pressed states. For a palette, the analogous pair #40DFA1 and #407FDF stays calm, while #DF5140 is the loudest partner.

What is #40cedf in CMYK for printing?

cmyk(71%, 8%, 0%, 13%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #40cedf warm or cool?

Cool — it scores 90 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #40DFB6; nudged cooler, #3EAAE1.

Work with #40cedf in the Color Lab