base 12 is a positional numeral system with twelve as its base. It uses 12 different digits for representing numbers. The digits for base 12 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, and b.

conversion table

base 12	base 10	base 12	base 10
1	≈ 1	b	≈ 11
2	≈ 2	10	≈ 12
3	≈ 3	11	≈ 13
4	≈ 4	12	≈ 14
5	≈ 5	13	≈ 15
6	≈ 6	14	≈ 16
7	≈ 7	15	≈ 17
8	≈ 8	16	≈ 18
9	≈ 9	17	≈ 19
a	≈ 10	18	≈ 20