#66C021 Color

#66C021 is rgb(102, 192, 33) in RGB, hsl(94, 71%, 44%) in HSL, and about cmyk(47%, 0%, 83%, 25%) in CMYK. It has no registered color name of its own — the closest is Kelly Green (#4CBB17), clearly related but distinguishable side by side at ΔE 6.36. Black text is the more readable choice on this background.

#66C021

HEX#66C021

RGBrgb(102, 192, 33)

HSLhsl(94, 71%, 44%)

HSVhsv(94, 83%, 75%)

CMYKcmyk(47%, 0%, 83%, 25%)

OKLCHoklch(72.4% 0.202 135.6)

LABlab(70.06% -46.64 63.14)

LCHlch(70.06% 78.50 126.46)

What #66C021 Is Called

Most hex codes have no name: there are 16.7 million of them and a few thousand registered names. These are the named colors nearest to #66C021, ordered by CIE76 distance in CIELAB. Anything under about ΔE 2 is a difference most people cannot see.

Kelly Green#4CBB17ΔE 6.36 Microsoft Green#7DB700ΔE 11.71 Green (RYB)#66B032ΔE 12.74 Yellow Green#9ACD32ΔE 15.32 Sheen Green#8FD400ΔE 15.57 Lime Green#32CD32ΔE 15.75

Browse the full index of named colors A-Z or every green in the library.

#66C021 Channel Values

How #66C021 breaks down in each color model. Hue is measured in degrees around the color wheel; saturation, lightness, and the CMYK inks are percentages.

Model	Channels	Notes
RGB	R 102 · G 192 · B 33	8-bit channels as sent to the display
HSL	H 94° · S 71% · L 44%	Easiest model for building lighter and darker variants
HSV	H 94° · S 83% · V 75%	Matches the picker in most design tools
CMYK	C 47% · M 0% · Y 83% · K 25%	Approximate ink mix; confirm with an ICC profile before printing
Luminance	2.3:1 vs white · 9.13:1 vs black	WCAG 2.2 relative-luminance contrast ratios

Text Contrast & Accessibility

WCAG 2.2 contrast ratios for text on a #66C021 background. AA requires 4.5:1 for normal text and 3:1 for large text; AAA requires 7:1. Contrast is one check, not a full accessibility review.

Fails AAWhite text2.3:1AA normal AA large AAA normal

TextBlack text9.13:1AA normal AA large AAA normal

Need a specific ratio against another background? Open #66C021 in the contrast checker.

Colors That Go With #66C021

Pairings derived from color-wheel relationships. The complementary color sits opposite #66C021; analogous colors sit beside it; triadic and split-complementary sets spread evenly around the wheel. Select any swatch for its own breakdown.

Base

Complementary

Analogous

Analogous

Triadic

Triadic

Split comp.

Split comp.

Tints & Shades of #66C021

Lighter tints and darker shades built by moving the lightness channel while holding hue and saturation, which is what you want for hover states, backgrounds, and text variants.

Tints

Shades

Want a full 50-950 ramp with semantic roles? Generate design tokens from #66C021.

How #66C021 Looks with Color Vision Deficiency

Simulated with the Viénot, Brettel & Mollon LMS projection model. Anomalous types are rendered as partial versions of the matching dichromacy, which is an approximation rather than a per-person clinical model.

Typical#66C021

Protanopia#B5B523

Protanomaly#9BB922

Deuteranopia#A9A92D

Deuteranomaly#93B329

Tritanopia#7BB5B5

Tritanomaly#73BA91

Achromatopsia#ABABAB

Test a full palette in the color blindness simulator.

Using #66C021 in Code

Copy-ready declarations for the places this color usually ends up.

CSS custom property--color-66c021: #66C021;

CSS backgroundbackground-color: #66C021;

Tailwind configcolors: { 'color-66c021': '#66C021' }

SwiftUIColor(red: 0.400, green: 0.753, blue: 0.129)

Android XML<color name="color_66c021">#66C021</color>

SVG fillfill="#66C021"

More Green Colors

#66C021 sits in the green family. These are its neighbours across that family's full range, each with its own breakdown.

000200 fdfff5 001f00 f7fee7 002400 f7fbf5 002c22 f5fffa 002e00 f5fff5 003300 f0fff0 008000 00db87 0d542b 20483f 33cc66 46c399 5ea500 728639 91e0b7 a3f5d8 bcd7bc d1ffed

#66C021 Frequently Asked Questions

What color is #66C021?

#66C021 is a mid-tone green — rgb(102, 192, 33) in RGB and hsl(94, 71%, 44%) in HSL. It carries no registered color name of its own; the closest named color is Kelly Green (#4CBB17), which is clearly related but distinguishable side by side at a CIE76 distance of 6.36.

What is the RGB value of #66C021?

#66C021 is rgb(102, 192, 33) — red 102, green 192, and blue 33 on the 0-255 scale.

What is the CMYK value of #66C021?

#66C021 converts to approximately cmyk(47%, 0%, 83%, 25%). CMYK output is a mathematical approximation for planning; confirm production print colors with your printer and ICC profile.

Should text on #66C021 be black or white?

Black text is the more readable choice. #66C021 scores 2.3:1 against white and 9.13:1 against black, and WCAG 2.2 asks for at least 4.5:1 for normal body text.

Can I write #66C021 as a CSS color keyword?

No. #66C021 is not one of the CSS color keywords, so it has to be written as a hex, rgb() or hsl() value. The closest keyword is yellowgreen (#9ACD32) at a CIE76 distance of 15.32, which is visibly different.

Open #66C021 in a Tool

Hex to RGB Hex to HSL Hex to CMYK Hex to OKLCH Hex to Pantone Build a palette Make a gradient

Keep exploring: every green in the color library, the guide to shades of green, or the full color library.