How to Geocode 20 Addresses Without Receiving an Over_Query_Limit Response

How do I Geocode 20 addresses without receiving an OVER_QUERY_LIMIT response?

No, there is not really any other way : if you have many locations and want to display them on a map, the best solution is to :

fetch the latitude+longitude, using the geocoder, when a location is created
store those in your database, alongside the address
and use those stored latitude+longitude when you want to display the map.

This is, of course, considering that you have a lot less creation/modification of locations than you have consultations of locations.

Yes, it means you'll have to do a bit more work when saving the locations -- but it also means :

You'll be able to search by geographical coordinates
- i.e. "I want a list of points that are near where I'm now"
Displaying the map will be a lot faster
- Even with more than 20 locations on it
Oh, and, also (last but not least) : this will work ;-)
- You will less likely hit the limit of X geocoder calls in N seconds.
- And you will less likely hit the limit of Y geocoder calls per day.

Google Geocoding API OVER_QUERY_LIMIT issue

The Geocoding API has a queries per second (QPS) limit. You cannot send more than 50 QPS.

This limit is documented at

https://developers.google.com/maps/documentation/geocoding/usage-and-billing#other-usage-limits

While you are no longer limited to a maximum number of requests per day (QPD), the following usage limits are still in place for the Geocoding API:
50 requests per second (QPS), calculated as the sum of client-side and server-side queries.

In order to solve your issue I would suggest using the Python client library for Google Maps API Web Services:

https://github.com/googlemaps/google-maps-services-python

This library controls QPS internally, so your requests will be queued properly.

I hope this helps!

Geocode OVER QUERY LIMIT workaround

First a note about Google's Terms of Service

It's easy to not think about stuff like this, but it does matter sometimes. Unless you want to join this group from earlier today which for some reason had their service disabled, make sure that you are showing a map to the user as you geocode these addresses. The TOS also prohibit bulk geocoding and storing the results for anything other than performance caching.

Not accusing! Just bringing to attention.

The programmer answer:

setTimeout's callback and geocode are both asynchronous functions. Right now with your code, while the response is still coming back from the API, you're starting your 1-second timer which also runs asynchronously while your loop continues to iterate immediately with no delay. After one second, the no-op is called once then discarded. This happens each time the loop is run.

So you're shooting off a thousand API requests at once. Then about 1 second later (give or take a few milliseconds), 1,000 no-ops will run.

Your calls to g.geocode need to be inside the callback function of setTimeout, and then the end of the callback function will need to set another timeout with itself inside it, until you are done. No more no-op.

If you want to more correctly "work around" the OVER_QUERY_LIMIT errors and other TOS restrictions (like geocoding en masse), you'll want to consider a commercial service that doesn't have such limits, something like LiveAddress (disclosure: I work at SmartyStreets).

what is the best geocode to get long and lot for a street address?

Geocode the addresses off-line and "cache" the results (for less than 30 days to comply with the terms of service), use the coordinates to display your markers.

More details: Geocoding Strategies article in the Google Maps Documentation.

GMap Geocoding: Over query limit

Google limits the number of geocoding requests per second. You can either wait or cache the results somewhere in your own database.

See this related question.