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KazamTools

Health & Fitness Calculators

Estimate calories, body mass index and more using the standard published formulas. These tools inform; they do not diagnose.

BMI CalculatorYour BMI, its WHO category and the healthy weight range for your height.BMR CalculatorHow many calories your body burns at complete rest, with three formulas compared.Body Fat CalculatorEstimate your body fat percentage with a tape measure, and see fat and lean mass.Calorie CalculatorHow many calories you need a day to maintain, lose or gain weight.Calorie Deficit CalculatorA daily calorie target for your goal weight and date, with safety checks and a realistic timeline.Ideal Weight CalculatorFour ideal body weight formulas and the healthy BMI range for your height, in kg and lb.Macro CalculatorYour daily protein, carbohydrate and fat in grams, for your goal and diet style.One Rep Max CalculatorEstimate the most you can lift once from a set of reps, and get your training weights.Ovulation CalculatorEstimate your most fertile days for the next six cycles. Not a method of contraception.Pace CalculatorPace, finish time or distance for any run, with splits and race predictions.Period CalculatorWhen your next periods are due, with fertile windows. Estimates only, not contraception.Pregnancy Due Date CalculatorYour estimated due date, how far along you are, and a week-by-week calendar.Protein CalculatorDaily protein in grams for your body weight and goal, plus how much to eat per meal.Sleep CalculatorBedtimes and wake-up times that line up with full 90-minute sleep cycles.TDEE CalculatorHow many calories you burn a day, and what to eat to maintain, lose or gain weight.Water Intake CalculatorA sourced estimate of your daily water needs, in litres, ounces and glasses.

Guides

Health calculators based on published formulas

These calculators use the standard formulas from medical and nutrition research, such as the World Health Organization BMI categories and the Mifflin–St Jeor equation for calorie needs. Each page explains the formula, its limits and who it does not suit.

Check your body mass index, estimate your daily calories with the TDEE calculator, and plan a safe rate of weight loss with the calorie deficit calculator.

Results are estimates for healthy adults and are not medical advice. Children, pregnant people, athletes and anyone with a medical condition should talk to a doctor or registered dietitian.

Frequently asked questions

Are these calculators medical advice?

No. They give general estimates. Talk to a doctor or registered dietitian before changing your diet or exercise.

Which formula is used for calories?

The default is the Mifflin–St Jeor equation, which studies found to be among the most accurate for adults. Other formulas are offered where useful.

Is BMI accurate for everyone?

No. BMI does not separate muscle from fat, and some populations have different risk cut-offs. Each page explains the limits.

Do you save my height or weight?

No. Everything is calculated in your browser and nothing is stored.