Calculate the distance between U.S. zip codes and find all zip codes within a given distance of a known zip code.
This project was started as a port to PHP 5 of a zip code class I wrote in 2005 for PHP 4. It also provides improvements based on suggestions from users of the original code.
This fork has been modified to be compatible with PHP 5.3+ as well as the GeoNames.org postal code database.
The PostalCode class is based on a MySQL table or view with the following fields:
country_code char(2)
postal_code varchar(20)
place_name varchar(180)
admin_name1 varchar(100)
admin_code1 varchar(20)
admin_name2 varchar(100)
admin_code2 varchar(20)
admin_name3 varchar(100)
admin_code3 varchar(20)
latitude float
longitude float
accuracy tinyint(1)
While the name of this table can be specified by the mysql_table class property,
the default table name is postal_codes.
Data Source
The class has been modified to work with the GeoNames.org postal code database, which is licensed under a Creative Commons Attribution 3.0 License. This database can be downloaded and imported into a MySQL database using the included schema.