Skip to content

#e7e521

a balanced, electric yellow · warm · closest name: Yellow

RGB
231, 229, 33
HSL
59°, 81%, 52%
CMYK
0, 1, 86, 9
Luminance
0.7314

At a glance

Every number on this page in one read: what #e7e521 is made of, how bright it looks, and which way it leans.

Hex
#e7e521
Hue
59°
yellow
Saturation
81%
electric
Lightness
52%
balanced
Brightness
91%
HSV value
Perceived
85%
weighted brightness
Luminance
0.7314
WCAG relative
Temperature
Warm
24/100 cool
Color family
Yellow
Tone
Electric
Best ink
Black
15.63:1
Closest name
Yellow
ΔE2000 5.7
Where it sits
Hue59° of 360°
Saturation81%
Lightness52%
Temperature
Warm ← → Cool24% cool

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

Every format

HEX#e7e521
RGBrgb(231, 229, 33)
HSLhsl(59, 81%, 52%)
CMYKcmyk(0%, 1%, 86%, 9%)
LABlab(88.5 -18.6 83.4)
LCHlch(88.5 85.5 102.6)
OKLCHoklch(0.895 0.188 109.0)
Decimal15197473
Display P3color(display-p3 0.906 0.898 0.129)

Copy-ready code

/* CSS */
color: #e7e521;
background-color: #e7e521;
/* Tailwind (arbitrary) */
class="text-[#e7e521] bg-[#e7e521]"
/* SCSS */
$brand: #e7e521;
/* SwiftUI */
Color(red: 0.906, green: 0.898, blue: 0.129)
/* Android */
Color.parseColor("#e7e521")
/* Flutter */
Color(0xFFE7E521)
/* Python / OpenCV (BGR) */
(33, 229, 231)

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 #e7e521 · 15.63:1
Use #000000AAA at every size.
Aa
White text · 1.34:1
AA fail · AA large fail · AAA fail
Aa
Black text · 15.63:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #e7e521 as text scores 1.34:1 on white and 15.63:1 on black.

Accessibility — WCAG contrast

Aa
#e7e521 on white: 1.34:1
AA ✗ fail · AA-large · AAA
Aa
#e7e521 on black: 15.63:1
AA ✓ pass · AA-large · AAA
true color
protanopia · #F9DB00
deuteranopia · #FBE138
tritanopia · #F8D6C4

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #e7e521 is pinned to step 600; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#FCFCF3
#F9F9E6
#F5F5C6
#F4F39A
#EFED67
#E9E734
#e7e521
#B8B614
#939210
#6B6A10
#43420A
Base = 600Lightest = 50 · #FCFCF3Darkest = 950 · #43420A
:root {
  --brand-50: #FCFCF3;
  --brand-100: #F9F9E6;
  --brand-200: #F5F5C6;
  --brand-300: #F4F39A;
  --brand-400: #EFED67;
  --brand-500: #E9E734;
  --brand-600: #e7e521;
  --brand-700: #B8B614;
  --brand-800: #939210;
  --brand-900: #6B6A10;
  --brand-950: #43420A;
  --brand: #e7e521;
  --brand-ink: #000000;
}

Colors that work with #e7e521

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#FAFAF4
Tinted page background
Border#EDECC0
Hairlines and dividers
Muted text#9B9A4B
Captions on the surface
Accent#1C52EC
Second voice, not a rival
Dark variant#73720C
Hover, pressed, headers
Light variant#FDFCE8
Selected rows, tints
Dark surface#242414
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 #e7e521

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#2123E7
Analogous left#E78221
Analogous right#86E721
Split-complement 1#2186E7
Split-complement 2#8221E7
Triadic 1#21E7E5
Triadic 2#E521E7
Tetradic#21E782

RGB percentages

Red90.6%
Green89.8%
Blue12.9%

CMYK percentages

Cyan0.0%
Magenta0.9%
Yellow85.7%
Key (black)9.4%

Color previews

#e7e521 text on a black background

contrast 15.63:1

Card sample

#e7e521 text on a white background

contrast 1.34:1

Card sample

CSS3 live lab

Text font color

The quick brown fox

color: #e7e521;
Background color
Panel with #e7e521 background
background-color: #e7e521;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #e7e521;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(231, 229, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(231, 229, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #e7e521;
background: linear-gradient(135deg, #e7e521, #65E721);

Monochromatic scale

Palettes built from #e7e521

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.

#e7e521 in the real world

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

Industries
RetailLeisureEnergyWarning systems
Common UI roles
ButtonsLinksFocus statesCharts
Print note

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

#e7e521, answered

What color is #e7e521?

#e7e521 is a balanced electric yellow, closest to Yellow (ΔE2000 5.7). It sits at 59° on the hue wheel with 81% saturation and 52% lightness, which reads as warm.

What is the RGB value of #e7e521?

rgb(231, 229, 33) — 231 red, 229 green and 33 blue out of 255, or 90.6% / 89.8% / 12.9% by channel.

Is #e7e521 a light or a dark color?

It is a light color. Relative luminance is 0.7314 and perceived brightness is 85%, so black text on it reaches 15.63:1.

Should I use black or white text on #e7e521?

Black. It scores 15.63:1 against #e7e521, versus 1.34:1 for white — AAA at any size.

What is the complementary color of #e7e521?

#2123E7 sits directly opposite on the wheel. Softer options are the split-complements #2186E7 and #8221E7, which give the same contrast with far less vibration.

What colors go well with #e7e521?

For interface work: #FAFAF4 as the surface, #EDECC0 for borders, #9B9A4B for secondary text, #1C52EC as an accent and #73720C for hover and pressed states. For a palette, the analogous pair #E78221 and #86E721 stays calm, while #2123E7 is the loudest partner.

What is #e7e521 in CMYK for printing?

cmyk(0%, 1%, 86%, 9%). 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 #e7e521 warm or cool?

Warm — it scores 24 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #E7A921; nudged cooler, #A1E91F.

Work with #e7e521 in the Color Lab