How many color options we have in html?

Answer 1

very much, people use hex/rgb codes to identify the colors, for now about 15-16 millions of codes

Answer 2

HTML mainly uses hex colors.

Hex colors work like this -

There are 16 values;
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F

Imagine the value of ‘A’ being something like 10.
This makes the values after 9 go like so:

A = 10
B = 11
C = 12
D = 13
E = 14
F = 15

Every hex code has 6 slots.
A hex code would be #xxxxxx, with x being any hex value.
So an example would be #00FF00, being green.

Each of these slots can contain any of the 16 values. Every combination of hex values is a different color. This gives us many, many possibilities for colors.

EDIT: I completely forgot about the 0 value, oops