MariaFitness started with a simple frustration: fitness advice is everywhere, but clear answers are rare. How many calories do you actually burn? What’s a healthy body fat percentage? Which heart rate zone should you train in? Most sites bury these answers under pop-ups and fluff. We built this site to do the opposite.
At its core, MariaFitness is a collection of free fitness calculators — for BMI, TDEE, body fat percentage, one-rep max, and heart rate zones — backed by plain-English guides that explain what your numbers mean and what to do next. No sign-ups, no paywalls, no gimmicks. Just tools and honest information.
What You’ll Find Here
- Free fitness calculators — quick, practical estimators for the numbers that matter: BMI, daily calorie burn (TDEE), body fat percentage, one-rep max, and heart rate zones.
- In-depth guides — every calculator comes with a full explainer: the formulas behind it, healthy ranges, common mistakes, and how to act on your result.
- The blog — practical articles on weight loss, gym training, running, nutrition, and healthy living, updated regularly.
How We’re Different
Three principles shape everything we publish:
- Numbers first, opinions second. We show the math — the actual formulas — so you can verify everything instead of taking our word for it.
- Written for humans. No jargon walls, no 3,000-word filler. If a concept takes two paragraphs, it gets two paragraphs.
- Health over hacks. We don’t do crash diets, miracle supplements, or 30-day transformations. Sustainable beats sensational, every time.
Who’s Behind MariaFitness?
MariaFitness is run by a small team of fitness writers and contributors who actually train — lifters, runners, and nutrition nerds who got tired of bad fitness content and decided to make better stuff. Have a read through the latest articles; the voice is ours, and we stand behind every word.
Work With Us
Think you can write something our readers would love? We accept guest contributions from coaches, writers, and fitness enthusiasts — read our write for us page for guidelines. For anything else — feedback, corrections, partnership ideas — reach out through our contact page. We read everything.
Frequently Asked Questions
Is MariaFitness free to use?
Completely. Every fitness calculator and every article on the site is free, with no account required and no premium tier hiding behind it.
Are your fitness calculators accurate?
They use well-established, peer-reviewed formulas (Mifflin-St Jeor for calorie burn, the Navy method for body fat, Epley/Brzycki for one-rep max). They’re estimators — accurate enough to plan around, typically within 5–15% of lab measurements — not medical devices.
Do you offer personal coaching or meal plans?
Not currently. MariaFitness focuses on free tools and education. Our guides are designed to help you coach yourself with solid numbers behind your decisions.
How can I contact you?
Through our contact page — we aim to reply within a few working days.