FitCalcs

Fitness & Health Guides

Science-based articles to help you understand the numbers behind your fitness goals.

How to Calculate Your BMI (And Why It's Not Enough)

Learn how BMI is calculated, what the ranges mean, and why body fat percentage may be a better measure of health. Free BMI calculator included.

2026-03-257 min read

TDEE Explained: Your Complete Guide to Daily Calories

What is TDEE? How is it calculated? Learn the Mifflin-St Jeor formula, activity multipliers, and how to use TDEE for weight loss, maintenance, or muscle gain.

2026-03-258 min read

How Much Protein Do You Really Need? Science-Based Guide

The definitive guide to daily protein intake for muscle building, fat loss, and general health. Based on the latest research, not bro science.

2026-03-259 min read

Is 1200 Calories Enough? The Truth About Very Low Calorie Diets

Why 1200-calorie diets are popular, when they're dangerous, and how to find your actual minimum calorie needs for safe, sustainable weight loss.

2026-03-257 min read

BMI vs Body Fat Percentage: Which Matters More?

BMI is simple but flawed. Body fat percentage tells the real story. Learn when to use each, their limitations, and how to measure both for free.

2026-03-256 min read

Zone 2 Training: The Complete Guide to Low-Intensity Cardio

Why Zone 2 is the most important training zone for health and longevity. How to find your Zone 2 heart rate, how often to train, and the science behind it.

2026-03-258 min read

How to Calculate Macros for Weight Loss: Step-by-Step

A simple, no-nonsense guide to calculating your macronutrient targets for fat loss. Protein, carbs, and fat ratios explained with real examples.

2026-03-258 min read

Body Recomposition: How to Build Muscle and Lose Fat at the Same Time

Yes, you can build muscle while losing fat. Learn who it works for, the science behind it, and exactly how to set up your calories and training.

2026-03-259 min read