Measuring your environmental footprint can serve as a good indication of environmental impact.
This process measures the amount of global hectares (1 hectare = roughly 2.5 acres) that humans require to exist.
Currently, the average US citizen requires 7 global hectares, compared to the global average of 2.7 hectares per person.
If the whole human population had the same ecological footprint as the average US citizen, we would need 3.9 Earths to sustain that level of consumption.
(McDonald, Charlotte. 2015. How many Earths do we need? BBC News Magazine, retrieved from https://www.bbc.com/news/magazine-33133712).