Free Health & Fitness Calculators
Research-backed tools to help you reach your health and fitness goals. All calculators are free, private, and require no sign-up.
Weight Management
Plan your calorie intake for weight loss, muscle gain, or maintenance
Calorie Deficit Calculator: How Much to Eat to Lose Weight
Find your daily calorie target for weight loss, how big a deficit to use and when you could reach your goal weight.
Weight Gain Calculator: Calories You Need to Gain Weight
Find how many calories a day you need to gain weight, with a calorie surplus that matches the weekly rate of gain you choose.
TDEE Calculator: Daily Calories for Weight Loss or Gain
See how many calories you burn a day from your age, height, weight and activity, and get calorie targets to lose, keep or gain weight.
Free Keto Calculator - Calculate Your Keto Macros for Weight Loss
Calculate your personalized keto macros with our free keto calculator. Get exact net carbs, protein, and fat targets for Standard, Targeted, or Cyclical ketogenic diets. Perfect for weight loss and fat burning.
Free Intermittent Fasting Calculator - Plan Your IF Schedule
Calculate your ideal intermittent fasting schedule with our free IF calculator. Get personalized eating windows for 16:8, 18:6, 20:4, and OMAD protocols with calorie and meal recommendations.
Free Body Recomposition Calculator - Lose Fat & Build Muscle
Calculate your ideal calorie and macro targets for body recomposition. Get personalized training day vs rest day nutrition for simultaneous fat loss and muscle gain.
Body Composition
Understand your body measurements, proportions, and health indicators
Body Mass Index (BMI) Calculator
Calculate your Body Mass Index (BMI) from your height and weight and see whether it falls in the underweight, healthy, overweight or obese range.
Free Body Fat Calculator - Estimate Your Body Fat Percentage
Calculate your body fat percentage using the U.S. Navy method. Understand your body composition and track your fitness progress.
FFMI Calculator: Fat-Free Mass Index for Men and Women
Calculate your fat-free mass index and normalized FFMI from height, weight and body fat to see how muscular you are for your height.
Body Shape Calculator: Find Your Body Type from Measurements
Enter your bust, waist and hip measurements to see whether your body shape is hourglass, pear, apple, rectangle or inverted triangle.
Waist-to-Hip Ratio (WHR) Calculator
Calculate your Waist-to-Hip Ratio (WHR) to assess body fat distribution and related health risks. This calculator provides instant results and health recommendations based on WHO guidelines.
Ideal Weight Calculator | What Should I Weigh?
Calculate your ideal body weight using multiple scientifically-validated formulas (Hamwi, Devine, Robinson, Miller). Free ideal weight calculator based on height, gender, and body frame with healthy weight range.
Nutrition
Get personalized macro, protein, and hydration targets for your goals
Macro Calculator: Daily Protein, Carbs and Fat
Work out how many grams of protein, carbs and fat to eat a day for weight loss, muscle gain or maintenance, based on your TDEE and goal.
Protein Calculator - How Much Protein Do You Need Per Day?
Calculate your daily protein needs with our free protein calculator. Find out how much protein you need based on your weight, activity level, and goals for weight loss, muscle building, or maintenance.
Water Intake Calculator | How Much Water Should I Drink?
Calculate your daily water intake needs based on body weight, activity level, climate, and exercise. Get personalized hydration recommendations with hourly schedules and meal-based targets.
Calories Burned Calculator: Walking, Running and Exercise
Calculate the calories burned during various physical activities based on your weight, activity type, and duration. Free exercise calorie calculator using MET values for accurate estimations.
Free Caffeine Calculator - Daily Intake, Metabolism & Sleep Impact
Calculate your daily caffeine intake, safe limits, and when to stop drinking caffeine for better sleep. Track coffee, tea, energy drinks, and more with our free caffeine calculator.
Free Peptide Reconstitution Calculator - How Much BAC Water To Add
Work out how much bacteriostatic water to add to a peptide vial. Enter your vial contents and your own dose, and get the water volume, the resulting mg/mL and mcg per unit concentration, and the exact mark to draw to on a U-100 insulin syringe.
Fitness & Metabolism
Measure your metabolic rate and strength benchmarks
One Rep Max Calculator | 1RM Calculator for Strength Training
Calculate your one rep max (1RM) using 7 scientifically-validated formulas. Get training percentages for strength, power, hypertrophy, and endurance. Perfect for powerlifting and strength training programs.
BMR Calculator: Basal Metabolic Rate for Men and Women
Find your basal metabolic rate with the Mifflin-St Jeor, Harris-Benedict, Katch-McArdle or Schofield formula, then see how many calories you burn at each activity level.
RMR Calculator: Find Your Resting Metabolic Rate
Estimate your resting metabolic rate, the calories your body uses at rest, from your age, sex, height and weight with the Mifflin-St Jeor or Harris-Benedict formula.
Free Sleep Calculator - Find Your Ideal Bedtime & Wake Time
Calculate your ideal bedtime or wake-up time based on 90-minute sleep cycles. Get personalized sleep recommendations using National Sleep Foundation guidelines.
Our Commitment to Accuracy and Reliability
At Nutrify, we understand the importance of providing accurate and reliable health and fitness tools. Our calculators are designed to give you valuable insights into your health, fitness, and nutrition. Here's what you can expect from our calculators:
- Research-Based: Each calculator is developed based on peer-reviewed scientific research and established health guidelines. We continuously update our tools to reflect the latest findings in health and nutrition science.
- Expert Validated: Our calculators are reviewed and validated by industry experts, including registered dietitians, certified fitness professionals, and healthcare practitioners. This ensures that our tools meet the highest standards of accuracy and reliability.
- User-Friendly Design: We've designed our calculators to be intuitive and easy to use, providing clear instructions and explanations every step of the way.
- Comprehensive Results: Our calculators don't just give you numbers — they provide context and actionable insights to help you understand and apply the results to your health and fitness journey.
- Privacy-Focused: Your health data is personal. Our calculators are designed with privacy in mind, and we do not store or share your individual results.
While our calculators provide valuable insights, they are not a substitute for professional medical advice. Always consult with a healthcare provider before making significant changes to your diet or exercise routine.
Frequently Asked Questions
Frequently Asked Questions
Find answers to common questions
Yes, all 17+ calculators on Nutrify are completely free to use with no sign-up required. Your data stays private — we do not store or share your individual results.
Our calculators use peer-reviewed scientific formulas such as the Mifflin-St Jeor equation for TDEE/BMR, the U.S. Navy method for body fat, and WHO guidelines for WHR. While they provide reliable estimates, individual results may vary. Always consult a healthcare provider for personalized medical advice.
If your goal is weight management, start with the TDEE Calculator to understand your daily calorie needs. From there, use the Macro Calculator or Calorie Deficit Calculator to plan your nutrition. For body composition goals, the BMI Calculator and Body Fat Calculator are great starting points.
Yes! The Macro Calculator, Protein Calculator, and Keto Calculator are specifically designed to help you plan meals. Pair them with the Nutrify app for AI-powered food tracking and personalized meal recommendations.
Most calculators are designed for adults aged 15-80. Activity level adjustments accommodate everyone from sedentary individuals to professional athletes. Some formulas like Katch-McArdle and Cunningham are better suited for athletic individuals with known body fat percentages.
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest. RMR (Resting Metabolic Rate) is similar but measured under less strict conditions. TDEE (Total Daily Energy Expenditure) includes BMR plus all activity — it represents your total daily calorie needs.