Which range is indicative of the bitterness for typical amber to brown beer?

The range of 15-25 IBU (International Bitterness Units) is indicative of the bitterness for typical amber to brown beers because these styles generally have a balanced flavor profile that includes a moderate level of bitterness. Amber and brown beers typically exhibit malt-forward characteristics, which can include sweet or toasty flavors from caramel malts, and this sweetness is often complemented rather than overwhelmed by bitterness.

This moderate bitterness range allows for the malt flavors to shine while still providing enough hoppy character to achieve a balanced drink. Higher IBU levels may start to overshadow the malt sweetness and could lead to an unbalanced flavor profile, while lower IBU levels may not deliver the complexity that one would expect from these styles. Therefore, the 15-25 IBU range is most representative of the intended flavor balance in amber to brown beers.