How do you know what color the number and letter configuration for color will be before hand

Question

Example #fff123 how to know before hand what color it is

Answer 1

Choose your colour and change background. it will give you hexadecimal value.

https://code.sololearn.com/WX195IlYDnkg/?ref=app

Answer 2

you can actually, its a six digit of hexadecimal (0 to f), separate them by 2 digits. each of this digits represent how much of intensity of basis color they have.

ff f1 23
R G B

as you can see we have a lot of red(ff) with almost equal amount of green(f1) and really low amount of blue (23).
so i guess its a vibrant yellow with a bit of orange color

Answer 3

Here is a good site to find hex color
There are many others... https://htmlcolorcodes.com/#