Why Use FitCalcHub?
Making meaningful progress towards your health and fitness goals requires more than general advice — it requires numbers that are specific to you. Generic recommendations like "eat 2,000 calories a day" or "drink 8 glasses of water" ignore the fact that calorie needs, hydration requirements, and protein targets all vary significantly based on body size, activity level, age, and individual goals.
FitCalcHub was built to solve exactly this problem. Every calculator on this site produces personalised results based on your own inputs, using the same evidence-based formulas that registered dietitians and sports scientists use in clinical practice. And unlike many fitness apps, everything here is completely free with no account, subscription, or data collection required.
How Our Calculators Work
We use the most widely validated formulas in exercise science and nutrition research. Our TDEE and BMR calculators are built on the Mifflin-St Jeor equation, which the Academy of Nutrition and Dietetics identifies as the most accurate resting metabolic rate formula for most adults. Our BMI calculator follows World Health Organization (WHO) thresholds. Protein recommendations are based on ISSN position stands. Hydration estimates align with National Academies of Sciences (NAS) guidelines. Activity multipliers are derived from published MET (Metabolic Equivalent of Task) tables.
All calculations happen instantly in your browser — no data is sent to a server, and no inputs are stored or tracked. Your privacy is fully preserved.
Which Calculator Should I Start With?
If you're new to tracking your fitness, the best place to start is the TDEE Calculator. Your Total Daily Energy Expenditure is the foundation of all calorie-based goals — knowing this number tells you exactly how many calories to eat to lose weight, maintain your weight, or build muscle. From there, you can use the Protein Calculator to set your daily protein target, and the Macro Calculator to distribute your calories across all three macronutrients. Everything else builds on this foundation.