Google Gmail API Pricing

Question

I'm using the Gmail API in a .Net project using the client_secret.json file.

Is that totally free, or is there any cost we need to pay for using Gmail API?

Also how long is the client_secret.json valid? Is there any expiry of the file?

Answer 1

The Gmail API, like Gmail itself, is (currently) a free service from Google.

(Note that Google does offer additional features for various apps, and charges for those features. See "Gsuite": https://gsuite.google.com/pricing.html?tab_activeEl=tabset-companies)

There are quota (usage) limits on the API.

For client-secrets.json (credentials used for server-to-server authentication), there is no expiration. Of course, a given client secret will stop working if you revoke it (delete it) through the Google developer console.

Answer 2

There is no billing marked for the Gmail API however there are usage limits: https://developers.google.com/gmail/api/v1/reference/quota