The very documentation already answers your question:
Each query sent to the Google Maps Distance Matrix API is Limited by the number of allowed Elements, Where the number of Origins times the number of Destinations defines the number of Elements.
Below, we have the limits of the API:
Users of the standard API:
- 2,500 free Elements per day
- Maximum of 25 Origins or 25 Destinations per request
- 100 Elements per query
- 100 Elements per 10 Seconds
That is, if per day you can seek 2500 elements and in each query there can be up to 100 elements, it is possible to make at least 25 darlings per day.
It is also worth noting that each request can have a maximum of 25 origins or 25 destinations, so in this case respectively they would be limited to 4 destinations or 4 origins. (25 * 4 = 100)
Yes based on this https://developers.google.com/maps/documentation/distance-matrix/usage-limits#premium-Usage-Limits seems to me also that every request is made
– Miguel