#A63303 Color

#A63303 is rgb(166, 51, 3) in RGB, hsl(18, 96%, 33%) in HSL, and about cmyk(0%, 69%, 98%, 35%) in CMYK. It has no registered color name of its own — the closest is Rust (#B7410E), clearly related but distinguishable side by side at ΔE 5.6. White text is the more readable choice on this background.

#A63303

HEX#A63303

RGBrgb(166, 51, 3)

HSLhsl(18, 96%, 33%)

HSVhsv(18, 98%, 65%)

CMYKcmyk(0%, 69%, 98%, 35%)

OKLCHoklch(48.9% 0.158 37.9)

LABlab(39.35% 46.74 50.79)

LCHlch(39.35% 69.02 47.38)

What #A63303 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 #A63303, ordered by CIE76 distance in CIELAB. Anything under about ΔE 2 is a difference most people cannot see.

Rust#B7410EΔE 5.6 Metallic Brown#AC4313ΔE 6.29 Rufous#A81C07ΔE 8.63 Chinese Red#AA381EΔE 9.29 Mahogany#C04000ΔE 10.64 Lemon Iced Tea#BD3000ΔE 11.21

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

#A63303 Channel Values

How #A63303 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 166 · G 51 · B 3	8-bit channels as sent to the display
HSL	H 18° · S 96% · L 33%	Easiest model for building lighter and darker variants
HSV	H 18° · S 98% · V 65%	Matches the picker in most design tools
CMYK	C 0% · M 69% · Y 98% · K 35%	Approximate ink mix; confirm with an ICC profile before printing
Luminance	6.78:1 vs white · 3.1:1 vs black	WCAG 2.2 relative-luminance contrast ratios

Text Contrast & Accessibility

WCAG 2.2 contrast ratios for text on a #A63303 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.

TextWhite text6.78:1AA normal AA large AAA normal

Fails AABlack text3.1:1AA normal AA large AAA normal

Need a specific ratio against another background? Open #A63303 in the contrast checker.

Colors That Go With #A63303

Pairings derived from color-wheel relationships. The complementary color sits opposite #A63303; 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 #A63303

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 #A63303.

How #A63303 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#A63303

Protanopia#565600

Protanomaly#7E4A00

Deuteranopia#6B6B00

Deuteranomaly#875A00

Tritanopia#A73030

Tritanomaly#A63124

Achromatopsia#5B5B5B

Test a full palette in the color blindness simulator.

Using #A63303 in Code

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

CSS custom property--color-a63303: #A63303;

CSS backgroundbackground-color: #A63303;

Tailwind configcolors: { 'color-a63303': '#A63303' }

SwiftUIColor(red: 0.651, green: 0.200, blue: 0.012)

Android XML<color name="color_a63303">#A63303</color>

SVG fillfill="#A63303"

More Brown Colors

#A63303 sits in the brown family. These are its neighbours across that family's full range, each with its own breakdown.

100c08 e17100 1b0d04 e15501 1c1917 e05e00 1f0800 e04000 1f1400 db8f00 241205 db7900 34240e 461901 503607 5c3f19 693507 7a2100 825221 8b6f47 993300 a8732e bd3000 cc3300

#A63303 Frequently Asked Questions

What color is #A63303?

#A63303 is a dark brown — rgb(166, 51, 3) in RGB and hsl(18, 96%, 33%) in HSL. It carries no registered color name of its own; the closest named color is Rust (#B7410E), which is clearly related but distinguishable side by side at a CIE76 distance of 5.6.

What is the RGB value of #A63303?

#A63303 is rgb(166, 51, 3) — red 166, green 51, and blue 3 on the 0-255 scale.

What is the CMYK value of #A63303?

#A63303 converts to approximately cmyk(0%, 69%, 98%, 35%). CMYK output is a mathematical approximation for planning; confirm production print colors with your printer and ICC profile.

Should text on #A63303 be black or white?

White text is the more readable choice. #A63303 scores 6.78:1 against white and 3.1:1 against black, and WCAG 2.2 asks for at least 4.5:1 for normal body text.

Can I write #A63303 as a CSS color keyword?

No. #A63303 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 darkred (#8B0000) at a CIE76 distance of 14.08, which is visibly different.

Open #A63303 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 brown in the color library, the guide to shades of brown, or the full color library.