base 26 is a positional numeral system with twenty-six as its base. It uses 26 different digits for representing numbers. The digits for base 26 could be 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f, g, h, i, j, k, l, m, n, o, and p.

conversion table

base 26	base 15	base 26	base 15
1	≈ 1	b	≈ b
2	≈ 2	c	≈ c
3	≈ 3	d	≈ d
4	≈ 4	e	≈ e
5	≈ 5	f	≈ 10
6	≈ 6	g	≈ 11
7	≈ 7	h	≈ 12
8	≈ 8	i	≈ 13
9	≈ 9	j	≈ 14
a	≈ a	k	≈ 15