About

Color model mismatches cause silent failures across design-to-development handoffs. A designer specifies HSL for perceptual uniformity while a print vendor demands CMYK and the stylesheet requires HEX. Manual conversion invites rounding errors that compound through a palette of dozens of swatches. This tool converts between six color representations - HEX (3/4/6/8-digit), RGB, RGBA, HSL, CMYK, and the 148 CSS named colors - using a canonical RGBA intermediate to eliminate cascading precision loss. Conversions follow the sRGB color space model. Note: CMYK output is a mathematical approximation; physical print accuracy depends on ICC profiles and ink characteristics that this tool does not model.

Formulas

All conversions route through a canonical RGBA tuple. The RGB-to-HSL decomposition proceeds as follows:

R′ = R255 , G′ = G255 , B′ = B255

C_max = max(R′, G′, B′) , C_min = min(R′, G′, B′) , Δ = C_max − C_min

L = C_max + C_min2

S =

{

0 if Δ = 0Δ1 − |2L − 1| otherwise

For RGB to CMYK:

K = 1 − C_max

C = 1 − R′ − K1 − K , M = 1 − G′ − K1 − K , Y = 1 − B′ − K1 − K

Where R, G, B are integer channel values in [0, 255], H is hue in degrees [0°, 360°), S and L are saturation and lightness as percentages, and C, M, Y, K are CMYK components as percentages. For pure black (K = 1), C = M = Y = 0.

Reference Data

Named Color	HEX	RGB	HSL	CMYK
aliceblue	#F0F8FF	rgb(240, 248, 255)	hsl(208, 100%, 97.1%)	cmyk(5.9%, 2.7%, 0%, 0%)
coral	#FF7F50	rgb(255, 127, 80)	hsl(16.1, 100%, 65.7%)	cmyk(0%, 50.2%, 68.6%, 0%)
cornflowerblue	#6495ED	rgb(100, 149, 237)	hsl(218.5, 79.2%, 66.1%)	cmyk(57.8%, 37.1%, 0%, 7.1%)
crimson	#DC143C	rgb(220, 20, 60)	hsl(348, 83.3%, 47.1%)	cmyk(0%, 90.9%, 72.7%, 13.7%)
darkcyan	#008B8B	rgb(0, 139, 139)	hsl(180, 100%, 27.3%)	cmyk(100%, 0%, 0%, 45.5%)
gold	#FFD700	rgb(255, 215, 0)	hsl(50.6, 100%, 50%)	cmyk(0%, 15.7%, 100%, 0%)
forestgreen	#228B22	rgb(34, 139, 34)	hsl(120, 60.7%, 33.9%)	cmyk(75.5%, 0%, 75.5%, 45.5%)
hotpink	#FF69B4	rgb(255, 105, 180)	hsl(330, 100%, 70.6%)	cmyk(0%, 58.8%, 29.4%, 0%)
indigo	#4B0082	rgb(75, 0, 130)	hsl(274.6, 100%, 25.5%)	cmyk(42.3%, 100%, 0%, 49%)
ivory	#FFFFF0	rgb(255, 255, 240)	hsl(60, 100%, 97.1%)	cmyk(0%, 0%, 5.9%, 0%)
khaki	#F0E68C	rgb(240, 230, 140)	hsl(54, 76.9%, 74.5%)	cmyk(0%, 4.2%, 41.7%, 5.9%)
lavender	#E6E6FA	rgb(230, 230, 250)	hsl(240, 66.7%, 94.1%)	cmyk(8%, 8%, 0%, 2%)
limegreen	#32CD32	rgb(50, 205, 50)	hsl(120, 60.8%, 50%)	cmyk(75.6%, 0%, 75.6%, 19.6%)
mediumaquamarine	#66CDAA	rgb(102, 205, 170)	hsl(159.6, 50.7%, 60.2%)	cmyk(50.2%, 0%, 17.1%, 19.6%)
midnightblue	#191970	rgb(25, 25, 112)	hsl(240, 63.5%, 26.9%)	cmyk(77.7%, 77.7%, 0%, 56.1%)
olivedrab	#6B8E23	rgb(107, 142, 35)	hsl(79.6, 60.5%, 34.7%)	cmyk(24.6%, 0%, 75.4%, 44.3%)
orangered	#FF4500	rgb(255, 69, 0)	hsl(16.2, 100%, 50%)	cmyk(0%, 72.9%, 100%, 0%)
orchid	#DA70D6	rgb(218, 112, 214)	hsl(302.3, 58.9%, 64.7%)	cmyk(0%, 48.6%, 1.8%, 14.5%)
peru	#CD853F	rgb(205, 133, 63)	hsl(29.6, 58.7%, 52.5%)	cmyk(0%, 35.1%, 69.3%, 19.6%)
rebeccapurple	#663399	rgb(102, 51, 153)	hsl(270, 50%, 40%)	cmyk(33.3%, 66.7%, 0%, 40%)
salmon	#FA8072	rgb(250, 128, 114)	hsl(6.2, 93.2%, 71.4%)	cmyk(0%, 48.8%, 54.4%, 2%)
seagreen	#2E8B57	rgb(46, 139, 87)	hsl(146.5, 50.3%, 36.3%)	cmyk(66.9%, 0%, 37.4%, 45.5%)
slateblue	#6A5ACD	rgb(106, 90, 205)	hsl(248.3, 53.5%, 57.8%)	cmyk(48.3%, 56.1%, 0%, 19.6%)
steelblue	#4682B4	rgb(70, 130, 180)	hsl(207.3, 44%, 49%)	cmyk(61.1%, 27.8%, 0%, 29.4%)
teal	#008080	rgb(0, 128, 128)	hsl(180, 100%, 25.1%)	cmyk(100%, 0%, 0%, 49.8%)
tomato	#FF6347	rgb(255, 99, 71)	hsl(9.1, 100%, 63.9%)	cmyk(0%, 61.2%, 72.2%, 0%)
turquoise	#40E0D0	rgb(64, 224, 208)	hsl(174, 72.1%, 56.5%)	cmyk(71.4%, 0%, 7.1%, 12.2%)
violet	#EE82EE	rgb(238, 130, 238)	hsl(300, 76.1%, 72.2%)	cmyk(0%, 45.4%, 0%, 6.7%)
wheat	#F5DEB3	rgb(245, 222, 179)	hsl(39.1, 76.7%, 83.1%)	cmyk(0%, 9.4%, 26.9%, 3.9%)
yellowgreen	#9ACD32	rgb(154, 205, 50)	hsl(79.7, 60.8%, 50%)	cmyk(24.9%, 0%, 75.6%, 19.6%)

Frequently Asked Questions

This converter performs a mathematical CMYK decomposition in the sRGB color space. Professional print workflows use ICC color profiles that account for ink absorption, paper type, and dot gain. The values here are device-independent approximations. For print-critical work, use the output as a starting reference and refine within a color-managed application like Adobe Illustrator.

A 3-digit HEX like #0F0 is expanded by doubling each digit: #00FF00. A 4-digit HEX like #0F0A is expanded to #00FF00AA, where the fourth pair represents the alpha channel. This follows the CSS Color Level 4 specification.

The converter supports RGBA via rgba(R,G,B,A) syntax and 8-digit HEX (e.g., #FF000080 for 50% transparent red). The alpha channel is preserved in the RGBA output and the HEX-8 output. HSL and CMYK outputs discard alpha as those models do not define transparency.

Yes. Several CSS named colors map to the same HEX value. For example, both "fuchsia" and "magenta" resolve to #FF00FF. When converting from HEX/RGB to a named color, the converter returns all matching names. If no CSS named color matches the exact value, the result shows "none".

Hue is rounded to 1 decimal place in degrees (0-360). Saturation and Lightness are rounded to 1 decimal place as percentages (0% - 100%). This provides sufficient precision for CSS usage while keeping values human-readable. The underlying conversion uses IEEE 754 double-precision arithmetic.

The tool accepts the traditional comma-separated syntax: rgb(R, G, B) and hsl(H, S%, L%). The modern space-separated syntax (rgb(R G B / A)) is not currently parsed. Use commas for reliable input.