10 free fitness calculators for BMI, body fat, calories, heart rate zones, 1RM, and more. All processing happens locally in your browser.
Tracking fitness progress requires accurate measurements and personalised targets. Our free fitness calculators help you understand your body composition, plan nutrition, optimise workouts, and monitor performance — all without any signup or cost. Processing happens locally in your browser for complete privacy.
The BMI calculator provides your Body Mass Index with health risk assessment and healthy weight range. While BMI is a screening tool, our body fat estimator using the US Navy method gives a more complete picture of body composition using simple tape measurements. The ideal weight calculator shows healthy weight ranges from multiple medical formulas (Robinson, Miller, Devine, Hamwi, and BMI range).
Understanding energy balance is key to weight management. Our calorie & BMR calculator estimates your basal metabolic rate and total daily energy expenditure based on activity level, then provides calorie targets for weight loss, maintenance, or muscle gain. The macro calculator breaks down daily protein, carb, and fat targets for different goals including weight loss, maintenance, muscle gain, and keto.
Strength athletes can use the one rep max (1RM) calculator which provides estimates from multiple formulas (Epley, Brzycki, Lombardi, Mayhew) to predict maximum lift capability. Runners will appreciate the pace calculator which converts between pace per km/mile, speed, and predicts race times for 5K, 10K, half marathon, and marathon based on current performance.
The heart rate zones calculator uses the Karvonen method to determine training zones from recovery to max effort — essential for effective cardio training. Our water intake calculator recommends daily hydration based on weight, exercise duration, and climate. The plank challenge timer provides progressive workout intervals for core strength training.
All tools are free, private, and evidence-based. Use them regularly to track progress toward your health and fitness goals.
Calculate your Body Mass Index with weight category and health risk.
Estimate body fat percentage using the US Navy method with tape measurements.
Calculate basal metabolic rate and daily calorie needs by activity level.
Estimate your maximum lift from reps and weight using multiple formulas.
Calculate training zones based on age and resting heart rate.
Convert between pace per mile/km, speed, and race finish times.
Find your healthy weight range using multiple medical formulas.
Calculate protein, carbs, and fat targets based on your goals and diet type.
Calculate daily water needs based on weight, activity, and climate.
Progressive plank timer with rest intervals and difficulty levels.