RYB is a color model based on Red Yellow and Blue base colors.
This color space is not very popular as there are many colors deffined via RGB or CMYK
that can not be converted to RYB.
However this color model is good for physical mixture of pigments.
So this color model may be usefull for model painters and artists
who uses acrylic and especially oil paints.
RGB Hex codes for RYB primary colors are:
RYB color model uses white background so to get white color set R=0 Y=0 and B=0.
The black color is a mixture of all the colors: R=1 Y=1 and B=1.
Note that it's impossimle to get absolutelly black color (in RGB meaning) using RYB color model.
How to convert from RYB to RGB
There isn't one-step formula to make such conversion.
The way to convert is a color wheel or cubic interpolation method.
The calculator above uses cubic interpolation. Enter some weight parts of
Red Yellow and Blue paints you mixt
(the range is 0..1 as only proportion is important) and click the button to get
RGB values of the mixture. Recomended webbrowser is IE.