Athlete Calculators
Your numbers for water, protein and caffeine, based on published sports science research. Enter your bodyweight once and every tab updates.
Your daily target is half your bodyweight in ounces, spread through the day. Before a hard session or competition, drink early instead of chugging at the last minute.
Find your sweat rate (optional)
Weigh yourself right before and right after a normal training session, in the same clothes. Towel off first.
Daily water target
--oz
Enter your bodyweight to start.
Based on the ACSM position stand on fluid replacement (Sawka et al., 2007) and rehydration research (Shirreffs et al., 1996).
Spread it out. Protein at every meal works better than one huge serving at dinner.
Daily protein target
--g
Enter your bodyweight to start.
Based on a meta-analysis of protein and strength training (Morton et al., 2018), protein during weight loss in athletes (Mettler et al., 2010) and the ACSM nutrition position statement (Thomas et al., 2016).
Caffeine works, but it steals sleep for hours after you take it. Test it in training first, never for the first time on competition day.
Starting dose
--mg
Enter your bodyweight to start.
Based on the ISSN caffeine position stand (Guest et al., 2021), a meta-analysis of caffeine and sleep (Gardiner et al., 2023) and the American Academy of Pediatrics statement on energy drinks (Schneider and Benjamin, 2011).
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