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We assessed the relationship between rates of biological energy utilization and the biomass sustained by that energy utilization, at both the organism and biosphere level. We compiled a dataset comprising >10,000 basal, field, and maximum metabolic rate measurements made on >2,900 individual species, and, in parallel, we quantified rates of energy utilization, on a biomass-normalized basis, by the global biosphere and by its major marine and terrestrial components. The organism-level data, which are dominated by animal species, have a geometric mean among basal metabolic rates of 0.012 W (g C)⁻¹and an overall range of more than six orders of magnitude. The biosphere as a whole uses energy at an average rate of 0.005 W (g C)⁻¹but exhibits a five order of magnitude range among its components, from 0.00002 W (g C)⁻¹for global marine subsurface sediments to 2.3 W (g C)⁻¹for global marine primary producers. While the average is set primarily by plants and microorganisms, and by the impact of humanity upon those populations, the extremes reflect systems populated almost exclusively by microbes. Mass-normalized energy utilization rates correlate strongly with rates of biomass carbon turnover. Based on our estimates of energy utilization rates in the biosphere, this correlation predicts global mean biomass carbon turnover rates of ~2.3 y⁻¹for terrestrial soil biota, ~8.5 y⁻¹for marine water column biota, and ~1.0 y⁻¹and ~0.01 y⁻¹for marine sediment biota in the 0 to 0.1 m and >0.1 m depth intervals, respectively.