We do our best to do exactly that. We geolocate consumers based on their IP addresses. Admittedly, that's a guess, but it's usually a pretty good one.
We set our calculations so that if we err, it's on the side of overgreening. We started Cloverly because of genuine concern about the carbon cost of the things we had delivered to us through ecommerce. Consumers who opt to have Cloverly green their shipments are thinking the same way. We're pretty sure they'd approve paying a few pennies—and it literally would be just pennies per order—to do a little extra greening.