set a location distance radius for our customers on php mysql website

Job ID: 36601064

Budget: $30 – $250 USD

our website generates leads on a contact form.
businesses register a location.
business can add keywords and locations.
currently the distance is 80k from each location.
if a contact form is submitted, if it is within 80k, business gets an email.
we want business to be able to set amount, e.g. type in numerical value 10k or 100k , etc.
Related categories: PHP JavaScript MySQL HTML Google Maps API