All Calculators
Every free CalcFit tool in one place — 62 calculators and a metabolic-age guide across 7 categories, no sign-up required.
No matching tools. Try a shorter term, such as “calorie” or “weight”.
Body Composition
Measure your BMI, body fat, frame size, and lean mass.
BMI Calculator
Calculate adult BMI and its screening category.
Ideal Weight Calculator
Compare four historical weight formulas.
Body Fat Percentage Calculator
U.S. Navy circumference method estimate.
Waist-to-Hip Ratio Calculator
WHO risk categories from waist and hip.
Waist-to-Height Ratio Calculator
Compare waist circumference with height.
Lean Body Mass Calculator
Boer formula fat-free mass estimate.
Army Body Fat Calculator
Legacy circumference estimate, not an Army assessment.
Body Frame Size Calculator
Small, medium, or large frame from wrist size.
Body Surface Area Calculator
Du Bois and Mosteller formulas.
Body Adiposity Index Calculator
BMI alternative using hip and height.
Ponderal Index Calculator
BMI alternative for tall or short people.
Skinfold Body Fat Calculator
Jackson-Pollock 3-site caliper method.
Calories & Nutrition
Calculate maintenance calories, deficits, macros, and nutrient targets.
TDEE Calculator
Your total daily energy expenditure.
BMR Calculator
Calories burned at complete rest.
Calorie Deficit Calculator
Daily deficit needed for your goal.
Macro Calculator
Protein, carb, and fat gram targets.
Calories Burned Calculator
15+ activities by weight and duration.
Water Intake Calculator
Daily hydration target by weight.
Protein Intake Calculator
Daily protein grams by goal.
Fiber Intake Calculator
Recommended daily fiber grams.
Calorie Surplus Calculator
Lean, standard, and aggressive bulk options.
Alcohol Calorie Calculator
Calories in beer, wine, and spirits.
Meal Calorie Split Calculator
Divide calories and macros across meals.
Intermittent Fasting Calculator
16:8, 18:6, 20:4, and OMAD windows.
Net Carbs Calculator
Total carbs minus fiber and sugar alcohols.
Calorie Cycling Calculator
Plan high and low intake days.
Exercise & Performance
Strength, cardio, and endurance tools for training and racing.
One Rep Max Calculator
Epley and Brzycki 1RM estimates.
Heart Rate Zone Calculator
Your 5 training zones by age.
Target Heart Rate Calculator
Karvonen heart rate reserve method.
VO2 Max Calculator
Cooper 12-minute run test estimate.
Running Pace Calculator
Pace, speed, and splits.
Race Time Predictor
Predict 5K to marathon times.
Marathon Time Calculator
Predict your 26.2-mile finish time.
Calories Burned Walking
By pace, weight, and duration.
Calories Burned Running
By pace, weight, and duration.
Calories Burned Cycling
By speed, weight, and duration.
Calories Burned Swimming
By stroke intensity and duration.
Steps to Calories Calculator
Convert your step count to calories.
Steps to Distance Calculator
Convert steps to miles or km.
Wilks Score Calculator
Compare powerlifting totals fairly.
FTP Calculator
Cycling functional threshold power.
Rowing Pace Calculator
Split time and power output.
Pregnancy & Growth
Due dates, pregnancy nutrition, and child growth tools.
Pregnancy Weight Gain Calculator
IOM guidelines by pre-pregnancy BMI.
Pregnancy Due Date Calculator
Naegele's Rule from your LMP.
Pregnancy Calorie Calculator
Calorie needs by trimester.
Child BMI Calculator & Percentile Guide
Ages 2-19, CDC-style categories.
Child Height Predictor
Mid-parental height estimate.
Sleep & Recovery
Sleep cycles, sleep debt, and nap timing.
Unit Converters
Quick conversions for weight, height, distance, and more.
Weight Converter
kg, lbs, stone, and ounces.
Height Converter
cm, feet and inches, meters.
Distance Converter
km, miles, meters, and feet.
Temperature Converter
Celsius, Fahrenheit, and Kelvin.
Volume Converter
Liters, gallons, cups, and ml.
Calorie Converter
kcal, kJ, and calories explained.
Running Pace Converter
min/km to min/mile.
Speed Converter
km/h, mph, and m/s.
Weight Management
Set realistic goals and track progress toward them.
BMI Prime Calculator
A simplified single-number BMI ratio.
Metabolic Age Guide
Compare your BMR to population averages.
Target Weight by Date Calculator
Get a real calendar date for your goal.
Muscle Gain Time Calculator
Realistic natural muscle-building timeline.
Weight Loss Percentage Calculator
Track progress as a percentage lost.