oauth 2.0 - Google access token expiration time

Question

When I obtain an access_token from the Google API, it comes with an expires_in value. According to the documentation, this value indicates "The remaining lifetime of the access token".

What are the units of this value?

Answer 1

The spec says seconds:

https://datatracker.ietf.org/doc/html/draft-ietf-oauth-v2-22#section-4.2.2

expires_in
    OPTIONAL.  The lifetime in seconds of the access token.  For
    example, the value "3600" denotes that the access token will
    expire in one hour from the time the response was generated.

I agree with OP that it's careless for Google to not document this.