It is possible to query our server from PHP scripts.  Here are the steps to follow:

 1. Register for API key. If you already have a key for Javascript interface, note that a separate registration is needed for PHP interface.

 2. Download the PHP library  topocoding.inc

 3. Use  the function topoGetAltitudes($places)  to get the altitudes of places in the array. Each place itself is also an array composed of real-numbered latitude and longitude. At most 280 places can be resolved at once. An array of integer altitudes in meters is returned. Here is a full source code of the simplest example for resolving the altitude of 2 hardcoded places. Modify the API key in this file to use your own registered key.

Please note that the free PHP API will be subject of the same bandwidth and count limitations as the free Javascript API, for commercial users we offer dedicated servers.