How can you determine the distance from the city limits to a point?

Question

Geolocation

Hi friends!

Tell me, how can I automatically determine (via api) the distance from the boundaries of the city X to point Y? What service can do this? It is necessary for delivery services in which free delivery from the border of the city (any, not necessarily the Moscow Ring Road / Ring Road) + 5 km.

Can it nominatim or something else? Guess who did this.