Skip to content
yellow · warm

#a3b821

a dark, vivid yellow · warm · closest name: Yellow Green

Token name suggestion: Shadow Citron

RGB
163, 184, 33
HSL
68°, 70%, 43%
CMYK
11, 0, 82, 28
Luminance
0.4218

#a3b821 is a dark vivid yellow, 68° on the wheel and 32/100 on the cool side. Put black text on it (9.44:1). As text it scores 2.23:1 on white — use #6D7B16 instead. Nearest name is Yellow Green, nearest Tailwind family is lime.

hsl(68 70% 43%)rgb(163 184 33)Base step 700AAA inkWarm

At a glance

Every number on this page in one read: what #a3b821 is made of, how bright it looks, and which way it leans.

Hex
#a3b821
Hue
68°
yellow
Saturation
70%
vivid
Lightness
43%
dark
Brightness
72%
HSV value
Perceived
66%
weighted brightness
Luminance
0.4218
WCAG relative
Temperature
Warm
32/100 cool
Color family
Yellow
Tone
Vivid
Best ink
Black
9.44:1
Closest name
Yellow Green
ΔE2000 7
Chroma
71.3
LCH, 0–130ish
OKLCH L
0.741
perceptual lightness
Tailwind
lime
500 · ΔE 8.8
Web-safe
#99CC33
nearest of 216
Where it sits
Hue68° of 360°
Saturation70%
Lightness43%
Saturation × lightness field

Left edge is grey, right edge is full chroma; top is white, bottom is black. The dot is #a3b821.

Temperature
Warm ← → Cool32% cool

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

Luminance by channel
Red18%
Green81%
Blue0%

Green carries most of what the eye calls brightness — that is why WCAG weights it 0.7152.

Every format

HEX#a3b821
HEX (8-digit)#a3b821ff
RGBrgb(163, 184, 33)
RGBArgba(163, 184, 33, 1)
HSLhsl(68, 70%, 43%)
HSV / HSBhsv(68, 82%, 72%)
HWBhwb(68 13% 28%)
CMYKcmyk(11%, 0%, 82%, 28%)
LABlab(71.0 -25.3 66.7)
LCHlch(71.0 71.3 110.7)
OKLCHoklch(0.741 0.164 117.9)
XYZ (D65)xyz(32.52, 42.18, 7.87)
Decimal10729505
Display P3color(display-p3 0.639 0.722 0.129)
Web-safe#99CC33

Copy-ready code

every platformclick to select
/* CSS */
color: #a3b821;
background-color: #a3b821;
/* CSS custom property */
--brand: #a3b821;
/* Tailwind (arbitrary) */
class="text-[#a3b821] bg-[#a3b821]"
/* SCSS */
$brand: #a3b821;
/* SwiftUI */
Color(red: 0.639, green: 0.722, blue: 0.129)
/* UIKit */
UIColor(red: 0.639, green: 0.722, blue: 0.129, alpha: 1)
/* Android XML */
<color name="brand">#A3B821</color>
/* Android Compose */
Color(0xFFA3B821)
/* Flutter */
Color(0xFFA3B821)
/* Python / OpenCV (BGR) */
(33, 184, 163)
/* Python / PIL (RGB) */
(163, 184, 33)
/* Java AWT */
new Color(163, 184, 33)
/* .NET */
Color.FromArgb(255, 163, 184, 33)
/* OpenGL / Unity (0–1) */
(0.6392f, 0.7216f, 0.1294f, 1f)
/* LaTeX */
\definecolor{brand}{RGB}{163,184,33}
modern cssclick to select
/* mix without leaving CSS */
background: color-mix(in oklab, #a3b821 85%, white);
border-color: color-mix(in oklab, #a3b821 40%, transparent);
/* theme-aware in one line */
color: light-dark(#606C13, #EAEED3);
/* relative colour syntax */
--hover: hsl(from #a3b821 h s calc(l - 7));

Design tokens

The same ramp in the four formats a team actually needs. Paste one and the whole palette lands with it.

css custom propertiesclick to select
:root {
  --brand-50: #FAFCF3;
  --brand-100: #F6F8E7;
  --brand-200: #EDF2CA;
  --brand-300: #E3EEA0;
  --brand-400: #D5E570;
  --brand-500: #C7DD41;
  --brand-600: #B8D025;
  --brand-700: #a3b821;
  --brand-800: #7B8A19;
  --brand-900: #5A6416;
  --brand-950: #383F0E;
  --brand: #a3b821;
  --brand-ink: #000000;
  --brand-surface: #FAFAF4;
  --brand-border: #E6EDC0;
  --brand-hover: #889A1C;
  --brand-pressed: #6D7B16;
}
@media (prefers-color-scheme: dark) {
  :root {
    --brand-surface: #222414;
    --brand-ink: #EAEED3;
  }
}
tailwind.config.jsclick to select
theme: {
  extend: {
    colors: {
      brand: {
        50: '#FAFCF3',
        100: '#F6F8E7',
        200: '#EDF2CA',
        300: '#E3EEA0',
        400: '#D5E570',
        500: '#C7DD41',
        600: '#B8D025',
        700: '#a3b821',
        800: '#7B8A19',
        900: '#5A6416',
        950: '#383F0E',
        DEFAULT: '#a3b821',
      },
    },
  },
}
scss mapclick to select
$brand: (
  '50': #FAFCF3,
  '100': #F6F8E7,
  '200': #EDF2CA,
  '300': #E3EEA0,
  '400': #D5E570,
  '500': #C7DD41,
  '600': #B8D025,
  '700': #a3b821,
  '800': #7B8A19,
  '900': #5A6416,
  '950': #383F0E,
);
$brand-base: #a3b821;
$brand-ink: #000000;

@function brand($step) { @return map-get($brand, $step); }
w3c design tokens (json)click to select
{
  "color": {
    "brand": {
      "50": { "$value": "#FAFCF3", "$type": "color" },
      "100": { "$value": "#F6F8E7", "$type": "color" },
      "200": { "$value": "#EDF2CA", "$type": "color" },
      "300": { "$value": "#E3EEA0", "$type": "color" },
      "400": { "$value": "#D5E570", "$type": "color" },
      "500": { "$value": "#C7DD41", "$type": "color" },
      "600": { "$value": "#B8D025", "$type": "color" },
      "700": { "$value": "#a3b821", "$type": "color" },
      "800": { "$value": "#7B8A19", "$type": "color" },
      "900": { "$value": "#5A6416", "$type": "color" },
      "950": { "$value": "#383F0E", "$type": "color" }
    },
    "brandInk": { "$value": "#000000", "$type": "color" }
  }
}

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 #a3b821 · 9.44:1
Use #000000AAA at every size.
Aa
12px
Aa
16px
Aa
24px
Aa
White text · 2.23:1
AA fail · AA large fail · AAA fail
Aa
Black text · 9.44:1 · recommended
AA pass · AA large pass · AAA pass
Reading the other direction: #a3b821 as text scores 2.23:1 on white and 9.44:1 on black.
Best tinted ink on it, if plain black or white feels flat: #606C13 at 2.58:1.

Make it accessible

A contrast checker tells you that you failed. This tells you what to ship instead — same hue, same saturation, lightness moved only as far as WCAG demands.

The quick fox
#6D7B16 · 4.67:1
AA on white−14% L
#6D7B16
The quick fox
#525D11 · 7.16:1
AAA on white−21% L
#525D11
The quick fox
#a3b821 · 9.44:1
AA on blackalready passes
#a3b821
The quick fox
#a3b821 · 9.44:1
AAA on blackalready passes
#a3b821

Large text — 24px regular or 18.66px bold and above — only needs 3:1, so #889A1C is enough for headings on white. Non-text elements such as icons, chart strokes and focus rings also sit at 3:1 under WCAG 2.2 (1.4.11).

Accessibility — WCAG contrast

Aa
#a3b821 on white: 2.23:1
AA ✗ fail · AA-large · AAA
Aa
#a3b821 on black: 9.44:1
AA ✓ pass · AA-large · AAA
Against the neutral ladder

Contrast is symmetric, so each row covers both directions: #a3b821 as text on that neutral, and that neutral as text on #a3b821.

NeutralRatioBoth directions
White2.23:1AaAa
Slate 502.13:1AaAa
Slate 1002.03:1AaAa
Slate 2001.81:1AaAa
Slate 3001.50:1AaAa
Slate 4001.15:1AaAa
Slate 5002.14:1AaAa
Slate 6003.40:1AaAa
Slate 7004.65:1AaAa
Slate 8006.57:1AaAa
Slate 9008.02:1AaAa
Black9.44:1AaAa
Colour vision deficiency
true color
protanopia · #C5AD00
deuteranopia · #C3AE31
tritanopia · #ADAD9D

Roughly one man in twelve has some form of colour vision deficiency. If any of the three panels above is hard to tell apart from a neighbouring colour in your palette, add a shape, an icon or a label so the meaning does not rest on hue alone.

Color scale — 50 to 950

A Tailwind-shaped ramp built around this exact hex. #a3b821 is pinned to step 700; the rest hold its hue and let saturation ease off at the extremes so the pale end never turns neon.

#FAFCF3
#F6F8E7
#EDF2CA
#E3EEA0
#D5E570
#C7DD41
#B8D025
#a3b821
#7B8A19
#5A6416
#383F0E
Base = 700Lightest = 50 · #FAFCF3Darkest = 950 · #383F0EText step on white = 900
Perceptual ramp — OKLCH

The same eleven steps expressed in OKLCH, where equal lightness numbers actually look equally spaced. HSL ramps go muddy in the yellows and washed out in the blues; this one does not. Modern browsers render it natively — the hex ramp above is the fallback.

50100200300400500600700800900950
oklch tokensclick to select
:root {
  --brand-50: oklch(0.97 0.041 117.9);
  --brand-100: oklch(0.94 0.065 117.9);
  --brand-200: oklch(0.88 0.098 117.9);
  --brand-300: oklch(0.80 0.128 117.9);
  --brand-400: oklch(0.72 0.151 117.9);
  --brand-500: oklch(0.64 0.164 117.9);
  --brand-600: oklch(0.56 0.164 117.9);
  --brand-700: oklch(0.48 0.154 117.9);
  --brand-800: oklch(0.40 0.137 117.9);
  --brand-900: oklch(0.32 0.115 117.9);
  --brand-950: oklch(0.24 0.090 117.9);
}

Colors that work with #a3b821

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#E6EDC0
Hairlines and dividers
Muted text#909B4B
Captions on the surface
Accent#1D2EBC
Second voice, not a rival
Dark variant#606C13
Hover, pressed, headers
Light variant#F9FBE9
Selected rows, tints
Dark surface#222414
Dark-mode background
Hover#889A1C
One step down in lightness
Pressed#6D7B16
Two steps down
Disabled#B3B891
Chroma pulled out
Focus ring#BBD518
Offset from the fill so it reads
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

In real components

The same eight roles, wired into the interface patterns you will actually build with them. Every state below is a computed value, not a mock-up.

Buttons and states
Save changesHoverPressedDisabled
OutlineSubtleLinkFocused
Form field
you@company.com

Focus ring uses the light variant so the field still reads as one shape.

Send me product updates
Notice
Your export is ready

The file stays available for seven days. Download it before it expires.

NewBetaDraft
Data
Storage used68%
Acme LtdActive
NorthwindTrial
GlobexActive

How to use #a3b821

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
  • Headers, footers and dark-mode surfaces
  • 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
  • Black text placed on it
  • Thin strokes and 1px borders — they disappear on light UI
  • Pairing with a same-lightness hue — edges vibrate
Minimum size as text on white
Not as text
Safe as a fill behind white type
No — use #606C13
Safe as a 1px border on white
No — use #889A1C

Meaning and mood

What a colour in this family tends to signal, and how this particular chroma and lightness change the reading.

optimisticalertcheap-and-cheerfulvisible

The most visible hue at low light levels, which is why it owns warnings, hazard tape and value retail.

This is a confident chroma: strong enough to lead a brand, restrained enough to live in an interface all day. The low lightness adds weight and formality.

Worth knowing

Almost never passes contrast against white. Treat it as a surface or a marker, not as text.

Reads as
  • FormalityHigh
  • EnergyMedium-high
  • Weight58/100
  • TemperatureWarm
  • ApproachabilityHigh

Colour associations are cultural and vary by market. Treat these as a starting point for a conversation with your audience, not a finding about them.

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#3621B8
Analogous left#B88121
Analogous right#58B821
Split-complement 1#2158B8
Split-complement 2#8121B8
Triadic 1#21A3B8
Triadic 2#B821A3
Tetradic#21B881
On the wheel
Base+30°−30°+120°+240°+180°68°

#a3b821 sits at 68°. Every dot is a harmony position and links to its own page in the table alongside.

RGB percentages

Red63.9%
Green72.2%
Blue12.9%
R · 0–255
163
0xa3
G · 0–255
184
0xb8
B · 0–255
33
0x21

CMYK percentages

Cyan11.4%
Magenta0.0%
Yellow82.1%
Key (black)27.8%

Total ink coverage is 121%. Most commercial presses cap around 300% — above that, sheets stop drying properly.

Color previews

#a3b821 text on a black background

contrast 9.44:1

Card sample

#a3b821 text on a white background

contrast 2.23:1

Card sample

#a3b821 on grey

2.03:1

#a3b821 on its own surface

2.12:1

#a3b821 on its dark surface

7.09:1

CSS3 live lab

Text font color

The quick brown fox

color: #a3b821;
Background color
Panel with #a3b821 background
background-color: #a3b821;
Text shadow — hex

Glowing headline

text-shadow: 2px 2px 8px #a3b821;
Text shadow — RGB

Soft neon halo

text-shadow: 0 0 14px rgba(163, 184, 33, 0.45);
Div box shadow
Elevated card
box-shadow: 0 12px 32px -8px rgba(163, 184, 33, 0.45);
Border & gradient
Gradient panel
border: 3px solid #a3b821;
background: linear-gradient(135deg, #a3b821, #3EB821);
Gradient text

Gradient headline

background: linear-gradient(90deg, #a3b821, #21B829);
-webkit-background-clip: text;
color: transparent;
Focus ring
Focused control
outline: 2px solid #a3b821;
outline-offset: 3px;
Underline & caret

Marked up text

text-decoration-color: #a3b821;
caret-color: #a3b821;
Left rule
Pull quote or callout
border-left: 4px solid #a3b821;
Ring + tint
Selected chip
background: #F9FBE9;
box-shadow: inset 0 0 0 2px #a3b821;
Conic badge
68%
background: conic-gradient(#a3b821 68%, #e2e8f0 0);

Transparency

What each alpha value actually composites to. The top row is #a3b821 over white; the bottom row is the same alpha over a checkerboard, so you can see what survives on a photo or a video.

Bottom row of hexes is the flattened result over white — use those when a design tool refuses transparency, or when you need a solid fallback.

alpha in every syntaxclick to select
rgba(163, 184, 33, 0.5)
rgb(163 184 33 / 50%)
#a3b82180
hsl(68 70% 43% / 50%)
color-mix(in srgb, #a3b821 50%, transparent)
Alpha8-digit hexFlat on white
10%#a3b8211a#F6F8E9
20%#a3b82133#EDF1D3
40%#a3b82166#DAE3A6
60%#a3b82199#C8D47A
80%#a3b821cc#B5C64D

Gradients from #a3b821

Six recipes, each built from this hex and shown with the exact CSS that produced it.

Elevation
Same hue, three lightnesses — safe anywhere
background: linear-gradient(135deg, #C5DC3A, #a3b821 45%, #606C13);
Duotone
A short hue run reads richer than a flat fill
background: linear-gradient(120deg, #a3b821, #2B9E1C);
Complement sweep
Loud — keep it behind large type only
background: linear-gradient(90deg, #a3b821, #3621B8);
Spotlight
Hero panels and app headers
background: radial-gradient(120% 120% at 20% 0%, #CDE054 0%, #a3b821 45%, #606C13 100%);
Soft wash
Section backgrounds that stay readable
background: linear-gradient(180deg, #FAFAF4, #ffffff);
Mesh
Ambient background, no image weight
background: radial-gradient(60% 60% at 15% 20%, #DA8F32 0%, transparent 60%), radial-gradient(55% 55% at 85% 15%, #56D226 0%, transparent 60%), radial-gradient(70% 70% at 50% 95%, #606C13 0%, transparent 65%), #a3b821;

Monochromatic scale

Palettes built from #a3b821

Shades — darker

Tints — lighter

Tones — desaturated

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.

#a3b821 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

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

On screens

Holds up across typical panel gamma. Still worth checking on an uncalibrated laptop, where mid-tones shift most.

In dark mode

Usable as-is on a dark surface at 9.44:1.

Explore nearby colors

Small, deliberate steps away from this hex — useful when you are hunting for the version of a colour that finally feels right.

#a3b821, answered

What color is #a3b821?

#a3b821 is a dark vivid yellow, closest to Yellow Green (ΔE2000 7). It sits at 68° on the hue wheel with 70% saturation and 43% lightness, which reads as warm.

What is the RGB value of #a3b821?

rgb(163, 184, 33) — 163 red, 184 green and 33 blue out of 255, or 63.9% / 72.2% / 12.9% by channel.

What is #a3b821 in HSL and HSV?

hsl(68, 70%, 43%) and hsv(68, 82%, 72%). HSL is what CSS takes; HSV is what your design tool's picker shows, which is why the saturation numbers rarely match.

Is #a3b821 a light or a dark color?

It is a mid-tone. Relative luminance is 0.4218 and perceived brightness is 66%, so black text on it reaches 9.44:1.

Should I use black or white text on #a3b821?

Black. It scores 9.44:1 against #a3b821, versus 2.23:1 for white — AAA at any size.

Is #a3b821 accessible on a white background?

#a3b821 on white scores 2.23:1, which fails WCAG AA at every size. Darken it to #6D7B16 to reach 4.5:1, or #525D11 for 7:1.

What is the complementary color of #a3b821?

#3621B8 sits directly opposite on the wheel. Softer options are the split-complements #2158B8 and #8121B8, which give the same contrast with far less vibration.

What colors go well with #a3b821?

For interface work: #FAFAF4 as the surface, #E6EDC0 for borders, #909B4B for secondary text, #1D2EBC as an accent and #606C13 for hover and pressed states. For a palette, the analogous pair #B88121 and #58B821 stays calm, while #3621B8 is the loudest partner.

What is #a3b821 in CMYK for printing?

cmyk(11%, 0%, 82%, 28%). This is a screen-to-ink approximation — ask your printer for a proof before committing to a run.

Is #a3b821 warm or cool?

Warm — it scores 32 on a scale where 0 is the warmest orange and 100 the coolest azure. Nudged warmer it becomes #B89521; nudged cooler, #6CBA1F.

Which Tailwind color is closest to #a3b821?

The lime family — its 500 step is #84cc16, ΔE2000 8.8 away. That is a visible difference, so define #a3b821 as a custom token rather than reaching for the built-in.

How do I use #a3b821 in Tailwind CSS?

Inline it as an arbitrary value with bg-[#a3b821] or text-[#a3b821], or register the whole ramp under theme.extend.colors.brand so you get bg-brand-500 and friends. The generated 50–950 scale on this page is ready to paste into your config.

What is #a3b821 with 50% opacity?

rgba(163, 184, 33, 0.5), or #a3b82180 in eight-digit hex. Over white that composites to #D1DC90; over black, #525C11.

Is #a3b821 a web-safe color?

No. The nearest web-safe colour is #99CC33, ΔE2000 6.9 away. The palette only matters for legacy displays and some email clients now.

What does the color #a3b821 mean?

As a yellow, it reads optimistic, alert, cheap-and-cheerful. The most visible hue at low light levels, which is why it owns warnings, hazard tape and value retail. At this chroma the effect is amplified — it will dominate whatever sits beside it.

What gradient works with #a3b821?

The safest is same-hue elevation: linear-gradient(135deg, #C5DC3A, #a3b821 45%, #606C13). For more colour, a short hue run to #2B9E1C keeps it rich without turning muddy.

Work with #a3b821 in the Color Lab

Every tool opens with this colour already loaded.

Every value on this page is computed from #a3b821 at request time — conversions, contrast ratios and ΔE distances are calculated, never looked up.