All calculators

Calculate Body Mass Index from weight and height using the standard kg/m² formula.

Estimate daily resting energy expenditure using the Mifflin-St Jeor equation for males and females.

Estimate body fat percentage using tape measurements via the U.S. Navy circumference method.

Estimate total daily energy expenditure by scaling BMR with an activity factor.

Estimate basal metabolic rate using the 1984 revised Harris-Benedict equation.

Estimate basal metabolic rate using lean body mass instead of age and sex.

Estimate body fat percentage from three skinfold sites using the Jackson-Pollock female-protocol equation.

Jackson-Pollock 7-site skinfold body fat percentage from caliper measurements.

Calculate Fat-Free Mass Index normalized for height using weight, height, and body-fat percentage.

Calculate lean body mass by subtracting fat mass from total weight.

Convert distances between kilometres and miles using the internationally standardised conversion factor.

Convert height between centimetres and feet/inches using the international standard conversion factor.

Convert running pace between min/km, min/mi, mph, and km/h using standard distance ratios.

Convert weight between kilograms and pounds using the internationally defined conversion factor.

Convert energy values between kilocalories (kcal) and kilojoules (kJ) using the standard 4.184 factor.

Convert between litres and US fluid ounces for hydration and beverage volumes.

Convert kilogram barbell targets to the nearest standard-plate combination in pounds per side.

Convert running and cycling speeds between mph, km/h, and m/s using international standard factors.

Convert resistance band stretch percentage to free-weight equivalent tension.

Convert sauna temperatures between Celsius and Fahrenheit using the standard thermodynamic formulas.

Estimate cycling power from speed, mass, drag area, rolling resistance, and gradient.

Calculate Coggan seven-zone power training ranges from your Functional Threshold Power (FTP).

Estimate Functional Threshold Power by applying a 0.95 factor to your 20-minute test result.

Calculate watts per kilogram and compare against duration-specific performance bands

Calculate Training Stress Score from workout duration, Normalized Power, and FTP.

Calculate gear inches from chainring, rear cog, and wheel diameter to compare drivetrain ratios.

Estimate climbing power from VAM and total mass using gravitational work principles.

Convert cycling speeds between miles per hour and kilometers per hour instantly

Calculate optimal chain length for single-speed and track bikes using chainring, cog, and chainstay measurements.

Calculate radial spoke length from rim ERD, flange radius, and spoke hole count.

Estimate calorie burn during cycling using speed-bracketed MET values and body weight.

Estimate calories burned during a run based on body weight, pace, and session duration.

Estimate swimming energy expenditure using MET values, body weight, and session duration.

Estimate calories burned walking at different paces using research-backed MET values.

Compare estimated calorie burn across running, cycling, swimming, walking, and resistance training.

Estimate calories burned during weight training sessions using MET-based energy expenditure equations.

Estimate caloric expenditure during rowing based on body weight, duration, and intensity level.

Estimate calories burned for any activity using its MET value, body weight, and duration.

Calculate five heart-rate training zones from age-based maximum heart rate using the Fox formula.

Calculate target heart rate zones using the Karvonen heart rate reserve method.

Estimate maximum heart rate using the classic 220-minus-age formula.

Estimate maximum heart rate using the Tanaka age-prediction equation (208 - 0.7 × age).

Calculate target heart rate zones from maximum heart rate and exercise intensity.

Calculate the drop in heart rate during the first minute after exercise stops.

Convert calorie percentages into daily protein, carb, and fat gram targets based on your TDEE.

Multiply body weight by grams-per-kilogram rate to estimate daily protein intake in grams.

Estimate the caloric contribution of ethanol in alcoholic beverages using ABV and serving size.

Estimate remaining caffeine in your system using exponential decay and a 5-hour half-life.

Estimate daily water intake using body weight and activity level with clinical hydration guidelines.

Estimate weekly calorie distribution across high-, medium-, and low-carb training days.

Scale recipe ingredient quantities proportionally when changing serving counts.

Estimate how many weeks to reach your target weight at a given weekly rate of change.

Calculate the percentage change between two weight measurements for progress tracking.

Calculate percentage strength gain or loss and weekly progression rate between two lift measurements.

Track percentage change in total training volume between two weeks.

Calculate average strength gain per personal record to track absolute progression step size.

Map work and deload weeks across your training cycle to visualize periodization structure.

Estimate your marathon finish time from a recent half-marathon performance using Riegel's formula.

Convert running pace between minutes per mile and minutes per kilometer instantly.

Estimate race finish time at a new distance using the Riegel formula and a known performance.

Calculate average running pace, speed, and split times from distance and duration.

Estimate running fitness (VDOT) from race performance using Jack Daniels's Running Formula equations.

Express any race result as a percentage of a reference standard using the WMA ratio formula.

Estimate time cost of vertical gain using the 12 s/mile per 100 ft coaching heuristic.

Convert a marathon goal time into per-kilometer pace and checkpoint splits for race-day pacing.

Calculate average steps per minute from total step count and run duration.

Break your run into equal splits and see the cumulative time at each distance marker.

Calculate Easy, Marathon, Threshold, and Interval paces from your VDOT score using Daniels' formula.

Convert treadmill speed in mph to running pace in minutes per mile and minutes per kilometer.

Split your race time into a slower first half and faster second half with adjustable pace gaps.

Estimate running power in watts from body weight and pace using a Stryd-style metabolic coefficient.

Calculate stride length from distance and step count using biomechanical gait-cycle definitions.

Calculate the exact plate combination needed per side to hit your target barbell weight in kilograms.

Calculate per-side plate loading to hit your target barbell weight with standard Olympic plates.

Normalize powerlifting totals across bodyweight and sex using the IPF's DOTS coefficient system.

Compare Epley, Brzycki, and Lombardi 1RM predictions side-by-side from a single lift.

Estimate your one-rep max from sub-maximal lifts using the Brzycki (1993) formula.

Estimate your one-rep max from submaximal lifts using the classic Epley formula.

Compare your lift to body weight and see which strength tier you fall into.

Compare powerlifting totals across body weights using the 2020 Wilks coefficient.

Calculate IPF Goodlift points for raw powerlifting totals adjusted by body weight and sex.

Estimate your one-rep max from submaximal lifts using the Lombardi formula.

Estimate your one-rep max using the OConner linear regression formula for sub-maximal lifts.

Estimate your one-rep max using the Wathen (1994) nonlinear regression formula.

Estimate your X-rep max from your known 1RM using the reverse Epley formula.

Convert RPE and rep count into estimated percentage of one-rep max using standard intensity tables.

Compare Olympic weightlifting totals across bodyweight categories using the IWF Sinclair formula.

Calculate working intensity as a percentage of one-rep max

Calculate total training volume load from sets, reps, and weight lifted.

Generate a four-set percentage-based warm-up ramp for barbell lifts, rounded to plate increments.

Convert swim distance and time into pace per 100 meters for training and race analysis.

Estimate your critical swim speed from 400 m and 200 m time-trial data.

Convert swim pace between 100-meter and 100-yard intervals using the standard meter-yard ratio.

Calculate your swimming efficiency by combining stroke count and lap time into one metric.

Convert swimming distances between meters and yards using the standard international conversion factor.

Divide swim time and distance into equal splits for even-pace training and race pacing.

Calculate bedtimes for complete 90-minute sleep cycles based on your desired wake time.

Calculate total HIIT session time and work-to-rest ratio from your interval structure.

Calculate total workout time for Tabata and custom interval training protocols

Calculate total rep volume across EMOM-style workouts with fixed reps per minute.

Find evidence-based rest intervals matched to your training goal—endurance, hypertrophy, or strength.

Estimate total session time from sets, work and rest intervals, and warm-up duration.