Color conversion math and formulas

These are the formulas used by our Color Calculator.
Each conversion formula is written as a "neutral programming function", easy to be translate in any specific computer language.
If you are searching for more generic information about color, on the Net there are several good sites devoted to color science, physics, psychology, physiology and technology.
Check our Links page or our FAQ page for a list of handy color references.

XYZ —> RGB

RGB —> XYZ

XYZ —> Yxy

Yxy —> XYZ

XYZ —> Hunter-Lab

Hunter-Lab —> XYZ

XYZ —> CIE-L*ab

CIE-L*ab —> XYZ

CIE-L*ab —> CIE-L*CH°

CIE-L*CH° —>CIE-L*ab

XYZ —> CIE-L*uv

CIE-L*uv —> XYZ

RGB —> HSL

HSL —> RGB

RGB —> HSV

var_R = ( R / 255 )                     //RGB from 0 to 255 var_G = ( G / 255 ) var_B = ( B / 255 ) var_Min = min( var_R, var_G, var_B )    //Min. value of RGB var_Max = max( var_R, var_G, var_B )    //Max. value of RGB del_Max = var_Max - var_Min             //Delta RGB value V = var_Max if ( del_Max == 0 )                     //This is a gray, no chroma... {    H = 0                                //HSV results from 0 to 1    S = 0 } else                                    //Chromatic data... {    S = del_Max / var_Max    del_R = ( ( ( var_Max - var_R ) / 6 ) + ( del_Max / 2 ) ) / del_Max    del_G = ( ( ( var_Max - var_G ) / 6 ) + ( del_Max / 2 ) ) / del_Max    del_B = ( ( ( var_Max - var_B ) / 6 ) + ( del_Max / 2 ) ) / del_Max    if      ( var_R == var_Max ) H = del_B - del_G    else if ( var_G == var_Max ) H = ( 1 / 3 ) + del_R - del_B    else if ( var_B == var_Max ) H = ( 2 / 3 ) + del_G - del_R    if ( H < 0 ) ; H += 1    if ( H > 1 ) ; H -= 1 } Top

HSV —> RGB

Range of HSL, HSB and HSV in popular applications

RGB —> CMY

CMY —> RGB

CMY —> CMYK

CMYK —> CMY

XYZ (Tristimulus) Reference values of a perfect reflecting diffuser