Calculators

Calories and Energy

How much you burn in a day or a session, and how to turn that into a target.

• TDEE CalculatorUse this TDEE calculator to find your maintenance calories in about a minute.
• Calorie CalculatorThis calorie calculator turns your maintenance calories into a gentle daily target.
• BMR CalculatorThis BMR calculator estimates the calories your body burns at rest, in about a minute.
• Calorie Deficit CalculatorUse this calorie deficit calculator to estimate how long a steady daily deficit could take to reach a goal weight.
• Katch-McArdle CalculatorUse this Katch-McArdle calculator to estimate your resting calorie burn from lean mass.
• Calories Burned CalculatorThis calories burned calculator estimates the energy you use walking, running, cycling or lifting.

Body Composition

Screening numbers for body size, shape and composition, with their limits explained.

• BMI CalculatorCheck your body mass index in under a minute with this BMI calculator.
• Body Fat CalculatorThis body fat calculator estimates your body fat percentage from a tape measure and the Navy method.
• Ideal Weight CalculatorThis ideal weight calculator shows what four classic formulas say about your height.
• Lean Body Mass CalculatorThis lean body mass calculator estimates everything in your body except fat, from three equations or your own body fat number.
• FFMI CalculatorThis FFMI calculator compares your lean mass with your height, using your weight and body fat percentage.
• Waist-to-Hip Ratio CalculatorUse this waist-to-hip ratio calculator to compare your waist and hip measurements with the WHO cut-off.
• Waist-to-Height Ratio CalculatorThis waist-to-height ratio calculator checks whether your waist is less than half your height.

Macros and Nutrition

Protein, carbs, fat and water, worked out for you.

• Macro CalculatorThis macro calculator splits your daily calories into protein, carbs and fat in about a minute.
• Protein CalculatorUse this protein calculator to see a daily protein range for your weight and goal.
• Water Intake CalculatorUse this water intake calculator to see how much you need in a day, and check your sweat loss after a session.

Cardio and Endurance

Heart rate, pace and the energy cost of cardio.

• Max Heart Rate CalculatorThis max heart rate calculator estimates your highest heart rate from your age with three published equations.
• Heart Rate Zones CalculatorUse this heart rate zones calculator to turn your age into moderate-intensity targets and a table of percentages.
• Running Pace CalculatorUse this running pace calculator to turn a distance and a time into pace per kilometer, pace per mile and speed.

Strength

Estimate a max without testing one.

• One Rep Max CalculatorThis one rep max calculator estimates your 1RM from a lighter set, so you can skip the max test.

How these calculators work

Every result is an estimate. Each page names its formula, explains the method, notes where it falls short and links the sources it relies on, with the date they were last reviewed. Nothing you type leaves the page, and you never need an email address to see your numbers.