Smart Calcs

Free Health Calculators

Health, fitness, and nutrition calculators with instant results. Pick a calculator below; no account required.

Pick a calculator below; no account required.

7-Step Health Plan

BMI to weight loss—Korean guided flow with saved progress.

1BMI 2BMR 3TDEE 4Calories 5Macros 6Body fat 7Weight loss

Timers & Tools

Stopwatch — lap splits for runs and workouts. Countdown Timer — set minutes and seconds with sound alert. Interval Timer — HIIT work/rest rounds for training. Pomodoro Timer — focus and break sessions.

Weight & Calories

Weight Loss Planner Weight Gain Planner Calorie Deficit Calculator Calorie Target Calculator Zig-Zag Calories Energy Expenditure (TDEE) TDEE Calculator BMR Calculator Meal Calorie Split Calories Per Meal Breastfeeding Calorie Add-On

Body & Composition

BMI Calculator Body Fat Estimator Ideal Weight Calculator Lean Body Mass Calculator Waist-to-Hip Ratio Waist-to-Height Ratio Body Adiposity Index Navy Body Fat Estimator Skinfold Body Fat Estimator Body Frame Size Estimator Body Surface Area Ponderal Index Pediatric BMI Calculator

Nutrition & Macros

Macro Calculator Protein Intake Calculator Carbohydrate Intake Fat Intake Fiber Intake Target Daily Water Intake Water Deficit Model Exercise Hydration Glycemic Load Calculator Intermittent Fasting Window Caffeine Intake Estimator Sodium Converter Vitamin D Unit Converter

Fitness Calculators

Calories Burned Running Pace Calculator One-Rep Max Estimator Heart Rate Zones Target Heart Rate Resting Heart Rate Calculator VO2 Max Estimator Activity Level (PAL) Daily Step Goal Sleep Debt Estimator Metabolism Age (Illustrative) Injury Recovery Planner

Pregnancy & Women's Health

Pregnancy Due Date Calculator Ovulation Calculator Breastfeeding Calorie Add-On

Clinical Education

eGFR Calculator (Educational) Corrected QT (QTc) Cholesterol Ratio Diabetes Risk Checklist Metabolic Health Screen Blood Pressure MAP Calculator Blood Alcohol Calculator

About Smart Calcs

Free calculators for education and planning—not medical advice.

Finance & everyday math

Loans, tips, percentages, age, dates, and unit converters live on our sister site.

Finance calculators → Daily tools → Tip calculator → Percentage calculator →