Fitness & Health Calculators
Reach your health and fitness goals faster with free, accurate health calculators. Track calories, understand your body, and plan your nutrition — all instantly and on any device, no sign-up needed.
Weight & Nutrition Calculators
- Calorie Calculator — Estimate your daily calorie needs for weight loss, maintenance, or muscle gain.
- Body Type Calculator — Discover your body type and what it means for your training and nutrition.
- BMI Calculator — Calculate your Body Mass Index and find your healthy weight range.
- BMR Calculator — Find your Basal Metabolic Rate and daily calorie burn.
- Body Fat Calculator — Estimate body fat percentage using the U.S. Navy tape-measure method.
- Calories Burned Calculator — Estimate calories burned by activity, weight and duration.
- Ideal Weight Calculator — Discover your healthy weight range for your height and gender.
- Macro Calculator — Calculate daily protein, carb and fat targets for your fitness goal.
- Pace Calculator — Find your running pace per km or mile from distance and time, plus speed in km/h and mph.
- Pregnancy / Due Date Calculator — Estimate your baby’s due date from your last period, plus current week and trimester.
- Protein Calculator — Find your ideal daily protein intake in grams based on weight, activity and goal.
- TDEE Calculator — Estimate your total daily calorie burn with the Mifflin-St Jeor equation.
- Target Heart Rate Calculator — Find your max heart rate and fat-burn, cardio and peak training zones.
- BAC Calculator — Blood alcohol estimate (Widmark).
- Carbohydrate Calculator — Daily carb needs in grams.
- Fat Intake Calculator — Daily fat grams range.
- GFR Calculator — Kidney function estimate.
- Lean Body Mass Calculator — Lean mass in kg.
- Ovulation Calculator — Fertile window dates.
- Period Calculator — Next period prediction.
- Height Calculator — Convert height between feet/inches and centimeters.
- Sleep Calculator — Find your ideal bedtime and wake time.
- Army Body Fat Calculator — U.S. Army tape-test body fat estimate.
- BMI Calculator for Women — BMI plus body fat estimate for women.
- Body Surface Area Calculator — BSA by Du Bois, Mosteller and Haycock formulas.
- Conception Calculator — Estimate your most likely conception date.
- Gestation Calculator — Pregnancy weeks, trimester and due date.
- Healthy Weight Calculator — Ideal weight range for your height.
- CFT Calculator
- AFT Calculator
- ASCVD Heart Risk Calculator
- Creatinine Clearance Calculator
- Peptide Calculator
- Weight Loss Calculator
Coming Soon
More fitness calculators are on the way.
Frequently Asked Questions
Are these fitness calculators really free?
Yes — every fitness and health calculator on Sigma Calculator is 100% free, with no sign-up and no limits.
What fitness calculators are available?
BMI, BMR, TDEE, calorie needs, body fat, macros, target heart rate, and more — covering weight, nutrition, and training.
How accurate is the BMI calculator?
It uses the standard CDC/WHO BMI formula. BMI is a screening measure — athletes with high muscle mass should also check body fat percentage.
Can these replace medical advice?
No — these tools are for education and planning. Always consult a qualified health professional for medical decisions.
Do these calculators work on mobile?
Yes — every calculator is 100% mobile friendly and works instantly on any phone, tablet, or desktop.