All Calculators at a Glance

Science-based health and fitness calculators — free, no registration.

Find all four core calculators (TDEE, BMI, Body Fat, Macros) plus 28 specialized variants for goals, professions, sports and life stages. All calculations use peer-reviewed formulas (Mifflin-St Jeor, U.S. Navy method, WHO classification).

Core Calculators

The four core tools for your health and fitness planning.

Guides & Background Articles

In-depth articles explaining the science behind our calculators.

8 min read

BMI vs. Body Fat Percentage – Which Number Tells You More About Your Health?

BMI and body fat percentage measure two different things. Using concrete examples, we show when BMI leads you astray, when it's still useful, and which number matters for which question.

7 min read

Calorie Deficit Chart for Women and Men – A Quick Overview by Age and Activity

How big a deficit is right for you depends on age, gender, and activity level. We give you the chart values directly — with moderate, larger, and maintenance numbers for every typical profile.

9 min read

How Many Calories Per Day to Lose Weight? The Honest Answer

How many calories you should eat per day to lose weight — with the formula, realistic examples for women and men, a table by activity level, and the most common mistakes that make diets fail.

8 min read

High-Protein Foods – The Ultimate List for Every Goal

The best protein sources compared head to head – animal, plant-based, snacks, shakes. With gram values per 100 g, calories, and a value-for-money rating for everyday life.

7 min read

How Fast Can You Lose Weight Safely? Realistic Numbers, Not Promises

5 kilos in 2 weeks? What's actually possible – with study numbers, the difference between fat and water, and why fast weight loss almost always backfires.

9 min read

How to Boost Your Metabolism – What Actually Works (and What Doesn't)

Tea, chili, drinking water? We separate the myths from the science-backed strategies that actually raise your metabolism in measurable ways – and explain why it comes down to NEAT, not miracle cures.

Frequently Asked Questions