Evaluating cow productivity in tropical beef systems is complex because efficiency depends on the integration of reproductive performance, calf growth, and cow maintenance requirements. The objective of this study was to compare alternative productivity indicators in Brahman and Bos taurus × Bos indicus cows managed under tropical conditions, with emphasis on their ability to account for cow size and consistently rank genotypes. Retrospective production records from 194 cows (46 Brahman and 148 F1 Bos taurus × Bos indicus) and 583 calves were analyzed. Productivity indicators included weaning weight (WW), kilograms of calf weaned per cow exposed to breeding (KCW), and ratios expressing calf output relative to cow weight or metabolic body weight. Data were analyzed using mixed models, paired comparisons, rank correlations, and linear regression. Cow genotype significantly affected all productivity measures (P < 0.05). Crossbred cows, particularly Angus × Zebu and Charolais × Zebu, showed superior performance compared with Brahman cows. Indicators expressing productivity relative to cow weight or metabolic weight provided greater discriminatory capacity and ranking consistency. Regression analysis revealed a significant negative relationship between cow weight and calf weaning weight (− 0.29 ± 0.05; P < 0.001), indicating that increased cow size was not associated with improved calf output. Productivity measures integrating reproductive success and cow size offer a more biologically meaningful assessment of efficiency under tropical conditions.