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#2aeffb

a balanced, electric cyan · cool · closest name: Cyan

RGB
42, 239, 251
HSL
183°, 96%, 58%
CMYK
83, 5, 0, 2
Luminance
0.6919

At a glance

Every number on this page in one read: what #2aeffb is made of, how bright it looks, and which way it leans.

Hex
#2aeffb
Hue
183°
cyan
Saturation
96%
electric
Lightness
58%
balanced
Brightness
98%
HSV value
Perceived
80%
weighted brightness
Luminance
0.6919
WCAG relative
Temperature
Cool
89/100 cool
Color family
Cyan
Tone
Electric
Best ink
Black
14.84:1
Closest name
Cyan
ΔE2000 5.2
Where it sits
Hue183° of 360°
Saturation96%
Lightness58%
Temperature
Warm ← → Cool89% 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#2aeffb
RGBrgb(42, 239, 251)
HSLhsl(183, 96%, 58%)
CMYKcmyk(83%, 5%, 0%, 2%)
LABlab(86.6 -40.7 -18.8)
LCHlch(86.6 44.8 204.8)
OKLCHoklch(0.869 0.142 201.6)
Decimal2813947
Display P3color(display-p3 0.165 0.937 0.984)

Copy-ready code

/* CSS */
color: #2aeffb;
background-color: #2aeffb;
/* Tailwind (arbitrary) */
class="text-[#2aeffb] bg-[#2aeffb]"
/* SCSS */
$brand: #2aeffb;
/* SwiftUI */
Color(red: 0.165, green: 0.937, blue: 0.984)
/* Android */
Color.parseColor("#2aeffb")
/* Flutter */
Color(0xFF2AEFFB)
/* Python / OpenCV (BGR) */
(251, 239, 42)

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 #2aeffb · 14.84:1
Use #000000AAA at every size.
Aa
White text · 1.42:1
AA fail · AA large fail · AAA fail
Aa
Black text · 14.84:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #2aeffb as text scores 1.42:1 on white and 14.84:1 on black.

Accessibility — WCAG contrast

Aa
#2aeffb on white: 1.42:1
AA ✗ fail · AA-large · AAA
Aa
#2aeffb on black: 14.84:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #DCE4FC
deuteranopia · #C1D0FC
tritanopia · #00F9F2

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #2aeffb 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.

#F1FDFD
#E4FAFC
#C1F7FA
#91F7FD
#5AF3FC
#2aeffb
#05E3F0
#04BDC8
#0397A0
#076D73
#044448
Base = 500Lightest = 50 · #F1FDFDDarkest = 950 · #044448
:root {
  --brand-50: #F1FDFD;
  --brand-100: #E4FAFC;
  --brand-200: #C1F7FA;
  --brand-300: #91F7FD;
  --brand-400: #5AF3FC;
  --brand-500: #2aeffb;
  --brand-600: #05E3F0;
  --brand-700: #04BDC8;
  --brand-800: #0397A0;
  --brand-900: #076D73;
  --brand-950: #044448;
  --brand: #2aeffb;
  --brand-ink: #000000;
}

Colors that work with #2aeffb

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#C0EAED
Hairlines and dividers
Muted text#4B969B
Captions on the surface
Accent#FF2650
Second voice, not a rival
Dark variant#02767D
Hover, pressed, headers
Light variant#E6FDFF
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 #2aeffb

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#FB362A
Analogous left#2AFB9E
Analogous right#2A87FB
Split-complement 1#FB2A87
Split-complement 2#FB9E2A
Triadic 1#FB2AEF
Triadic 2#EFFB2A
Tetradic#9E2AFB

RGB percentages

Red16.5%
Green93.7%
Blue98.4%

CMYK percentages

Cyan83.3%
Magenta4.8%
Yellow0.0%
Key (black)1.6%

Color previews

#2aeffb text on a black background

contrast 14.84:1

Card sample

#2aeffb text on a white background

contrast 1.42:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #2aeffb;
Background color
Panel with #2aeffb background
background-color: #2aeffb;
Text shadow — hex

Glowing headline

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

Soft neon halo

text-shadow: 0 0 14px rgba(42, 239, 251, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(42, 239, 251, 0.45);
Border & gradient
Gradient panel
border: 3px solid #2aeffb;
background: linear-gradient(135deg, #2aeffb, #2A64FB);

Monochromatic scale

Palettes built from #2aeffb

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.

#2aeffb 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

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

#2aeffb, answered

What color is #2aeffb?

#2aeffb is a balanced electric cyan, closest to Cyan (ΔE2000 5.2). It sits at 183° on the hue wheel with 96% saturation and 58% lightness, which reads as cool.

What is the RGB value of #2aeffb?

rgb(42, 239, 251) — 42 red, 239 green and 251 blue out of 255, or 16.5% / 93.7% / 98.4% by channel.

Is #2aeffb a light or a dark color?

It is a light color. Relative luminance is 0.6919 and perceived brightness is 80%, so black text on it reaches 14.84:1.

Should I use black or white text on #2aeffb?

Black. It scores 14.84:1 against #2aeffb, versus 1.42:1 for white — AAA at any size.

What is the complementary color of #2aeffb?

#FB362A sits directly opposite on the wheel. Softer options are the split-complements #FB2A87 and #FB9E2A, which give the same contrast with far less vibration.

What colors go well with #2aeffb?

For interface work: #F4FAFA as the surface, #C0EAED for borders, #4B969B for secondary text, #FF2650 as an accent and #02767D for hover and pressed states. For a palette, the analogous pair #2AFB9E and #2A87FB stays calm, while #FB362A is the loudest partner.

What is #2aeffb in CMYK for printing?

cmyk(83%, 5%, 0%, 2%). 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 #2aeffb warm or cool?

Cool — it scores 89 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #2AFBBA; nudged cooler, #28C1FD.

Work with #2aeffb in the Color Lab