Are Google Maps API limits applied to key or to cloud project?

Question

Google Maps API (Directions API) has limit of 50 queries per second (QPS): https://developers.google.com/maps/faq#usage_apis

However, I need more than just 50 as my web app serves lots of users and 50 QPS is totally not enough , I get failure responses from Google Directions API all the times.

I can create multiple keys to use but the matter is the limit of 50 QPS applies to a single key or applies to the whole Google Cloud project ? It doesn't specify in the link above.

If it applies to the whole project, there's no point to create multiple keys. Any one ever tried to identify this out?

Answer 1

Quotas are scoped to Projects; multiple API Keys in a project do not impact the project's quotas.

API Keys are often (not always) a way to provide otherwise unauthenticated users with a form of bearer token to access a Google API|service and APIs and services are always associated with a project.

If you lose (control of) an API Key, anyone using it (until it is deleted) is able to use the Key to access its project's resources.

For this reason, you may wish to use different API Keys for different subsets of your user base.

And|Or you may wish to employ a system in which you "rotate" API Keys (create new and eventually replace existing) to effectively require your users to reconfirm their use of your app.