Health & Fitness Calculators

Understand your body with BMI, BMR, body-fat and calorie tools, plan fitness and pregnancy milestones, and check hydration, sleep and clinical dosing safely.

20 free tools · no sign-up, no ads
Age Calculator
Find your exact age in years, months, days, and even seconds.
Health Calculator
BMI Calculator
Check your Body Mass Index and understand your health range.
Health Calculator
BMR Calculator
Calculate resting calories and daily energy needs.
Health Calculator
Body Fat Percentage
Estimate body fat percentage using Navy standards.
Health Calculator
Calorie Calculator
Daily calorie needs based on activity level.
Health Calculator
Calories Burned
Calories burned across 25+ activities.
Health Calculator
Daily Water Intake
Calculate your recommended daily hydration targets.
Health Calculator
Dehydration Calculator
Estimate fluid deficit and the water needed to rehydrate.
Health Calculator
Diet Carbon & Water Footprint
See the CO2 and water hidden in your weekly diet.
Health Calculator
Heart Rate Zones
Target training zones from your max heart rate.
Health Calculator
Ideal Body Weight
Find target ideal weight ranges based on height and gender.
Health Calculator
Insulin Dose Calculator
Calculate mealtime insulin from carbs and correction factor.
Health Calculator
Ovulation Calculator
Predict fertile windows and next periods.
Health Calculator
Pediatric Dose Calculator
Convert adult doses into safe child doses by weight and BSA.
Health Calculator
Pregnancy Due Date
Calculate baby due dates and track gestational milestones.
Health Calculator
Running Pace
Compute pace, time, or distance for runs and races.
Health Calculator
Screen Time Impact
See what your daily screen hours add up to over a year.
Health Calculator
Sleep Calculator
Find the best bedtimes based on sleep cycles.
Health Calculator
Sleep Cycle Calculator
Find the best bedtime and wake time from 90-minute cycles.
Health Calculator
TDEE & Goal Weight
Get maintenance calories and a realistic goal-weight timeline.
Health Calculator