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.
BMI Calculator
Calculate your Body Mass Index in metric or imperial units.
TDEE Calculator
Find your Total Daily Energy Expenditure based on age, gender, and activity.
Macro Calculator
Turn your TDEE into daily protein, carb, and fat targets.
Body Fat Calculator
Estimate your body fat percentage using the U.S. Navy Method.
Specialized Variants
Tailored calculators for your goal, profession or life situation.
BMI Calculator(3)
TDEE Calculator(8)
Macro Calculator(1)
Guides & Background Articles
In-depth articles explaining the science behind our calculators.
BMR vs TDEE: What’s the Difference (And Which One Should You Use)?
BMR is the energy you burn at complete rest. TDEE is your real-world daily burn, including activity and digestion. Use TDEE to set goal calories; use BMR only as a component in the calculation.
How to Calculate Macros – Simple, Actionable Method
A clear macro‑calculation method using your TDEE and goal. Set protein, fat, then fill carbs. Includes a full example and common mistakes.
How to Calculate Your TDEE (Total Daily Energy Expenditure)
A clear, step-by-step guide to calculate your TDEE correctly using Mifflin–St Jeor and activity factors, plus common mistakes to avoid.
How to Create a Calorie Deficit That Works (Without Hunger and Burnout)
Knowing your TDEE is step one. But creating a calorie deficit that actually leads to fat loss—without making you miserable—is the real challenge. This practical guide shows you how.
Your Health Plan, Simplified: Use BMI, TDEE, and Macros in 3 Easy Steps
Feeling lost with health and nutrition advice? It's time to stop guessing. This guide shows you how to use three simple numbers—BMI, TDEE, and Macros—to build a personalized health plan that actually works. All in under 10 minutes.
Is BMI a Good Measure of Health? (The Honest Answer)
You just got your BMI result. Now what? Before you celebrate or panic, it's crucial to understand what this number really means. Here’s the honest truth about what BMI can—and can't—tell you about your health.