Simple, transparent calculators with clear assumptions and limitations. Every result is an estimate, not a diagnosis.
Tool 01
Estimates maintenance calories using the Mifflin-St Jeor formula, then applies your goal.
Fill in the form to see your estimate here.
Tool 02
Combines body weight, activity time and climate into a daily fluid target.
Fill in the form to see your estimate here.
Tool 03
Times sleep or wake times in full 90-minute cycles, with a 15-minute buffer to fall asleep.
Choose a time to see suggested cycles here.
Tool 04
Estimates training zones from age, refined with the Karvonen method if you add a resting heart rate.
Enter your age to see estimated zones here.
Our guides walk through the assumptions each calculator makes.
Browse guides