0 providers are within the given radius.
This demo shows how to calculate how many points are within a radius using Leaflet. It uses jquery-geocodify, which creates a form that allows readers to enter their address and have it plotted on the map.
To use, enter an address and then enter a radius. Under results will be the number of markers within the given radius. You can also drag the marker on the map; the number will update automatically.
More information is available here. Code was originally used here.
Code by Chris Essig.