php-geohash

Simple GeoHash class for PHP

Characteristic

Algorithmic processes clearly

Decimal - Base

Decimal	0	1	2	3	4	5	6	7	8	9	10	11	12	13	14	15
Base	32	0	1	2	3	4	5	6	7	8	9	b	c	d	e	f

Decimal	16	17	18	19	20	21	22	23	24	25	26	27	28	29	30	31
Base	32	h	j	k	m	n	p	q	r	s	t	u	v	w	x	y

Errors

geohash length	lat bits	lng bits	lat error	lng error	km error
1	2	3	±23	±23	±2500
2	5	5	±2.8	±5.6	±630
3	7	8	±0.70	±0.70	±78
4	10	10	±0.087	±0.18	±20
5	12	13	±0.022	±0.022	±2.4
6	15	15	±0.0027	±0.0055	±0.61
7	17	18	±0.00068	±0.00068	±0.076
8	20	20	±0.000085	±0.00017	±0.019

Draft

Ref

https://en.wikipedia.org/wiki/Geohash