base 22 is a positional numeral system with twenty-two as its base. It uses 22 different digits for representing numbers. The digits for base 22 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f, g, h, i, j, k, and l.

conversion table

base 22	base 18	base 22	base 18
1	≈ 1	b	≈ b
2	≈ 2	c	≈ c
3	≈ 3	d	≈ d
4	≈ 4	e	≈ e
5	≈ 5	f	≈ f
6	≈ 6	g	≈ g
7	≈ 7	h	≈ h
8	≈ 8	i	≈ 10
9	≈ 9	j	≈ 11
a	≈ a	k	≈ 12