According to Google Map's Geocode API documentation:
https://developers.google.com/maps/documentation/geocoding/index#GeocodingRequests
you can simply make a call to the geocode request address like this:
However, according to this section, there is a usage limit of 2500 requests per day.
- Because the request url doesn't contain any type of API key parameter, how is Google tracking the query limit? Is it simply by the client's IP address?
- I have a Google Maps API v3 key, which says that there is a "Courtesy limit: 25,000 requests/day". Is this something different than the Geocoding API? Or can I somehow use my Google Maps API key with the Geocoding API so that I can potentially do more than 2500 requests per day?
Yes it is by ip address.
25,000 is for map loads per day
2,500 is for geocodes per day
If you want more you need to get an account with them and last I checked it cost $10,000 to start.
来源：https://stackoverflow.com/questions/12500329/google-maps-geocode-api-how-to-access-with-your-api-key