Health Calculators
BMI, calories, macros, body fat — science-backed tools with every formula explained.
BMI Calculator
Body Mass Index in metric or imperial — with BMI category and healthy range.
Use Calculator →Calorie Calculator (TDEE)
Daily calorie needs using Mifflin-St Jeor — 5 activity levels, weight goal targets.
Use Calculator →BMR Calculator
Basal Metabolic Rate — calories burned at rest, plus TDEE and weight loss target.
Use Calculator →Macro Calculator
Daily protein, carbs, and fat targets in grams from calories and macro split.
Use Calculator →Body Fat Calculator
Estimate body fat % using the US Navy circumference method — male and female.
Use Calculator →Pregnancy Due Date Calculator
Calculate estimated due date from LMP, conception date, or ultrasound
Use Calculator →Ovulation Calculator
Predict fertile window and ovulation date from last period and cycle length
Use Calculator →Ideal Weight Calculator
Healthy weight range using Hamwi, Devine, Robinson, and Miller formulas
Use Calculator →Pace Calculator
Running pace, speed, and finish time for 5K, 10K, half marathon, marathon
Use Calculator →Alcohol Unit Calculator
Units in any drink from volume and ABV. Compare to UK NHS weekly limit
Use Calculator →Sleep Calculator
Best bedtime or wake-up time using 90-minute sleep cycles
Use Calculator →Sleep Cycle Calculator
Pick a target number of 90-minute cycles and get the matching time
Use Calculator →How Much Sleep Do I Need?
Recommended sleep hours by age, from newborns to older adults
Use Calculator →Nap Calculator
Power nap, NASA nap, coffee nap, or full-cycle nap wake times
Use Calculator →Sleep Debt Calculator
See your cumulative sleep debt from the last 7 nights
Use Calculator →