My Wellness Calc is a collection of free, science-backed calculators and guides designed to help you make better everyday health decisions — without paywalls, popups, or prescriptions.
Every tool on this site is completely free to use. No account, no email, no payment — ever. Just open it and use it.
Every formula and recommendation on this site is grounded in established research. We cite our sources and explain our methods.
We tell you what the science supports — and what it doesn't. No miracle claims, no fear-mongering, no supplement upsells disguised as advice.
Your calculator inputs never leave your browser. We don't store, sell, or share any health data you enter on this site.
Every tool is designed to work perfectly on phone, tablet, or desktop. Fast, responsive, and no app download required.
We add new tools based on reader requests and update existing ones when research evolves. This is a living project.
Health information online is often confusing, contradictory, or hidden behind sign-up walls. A simple question — "how many calories should I eat?" — leads you to a 3,000-word blog post that ends with a $79/month subscription.
We built My Wellness Calc to be the opposite: a set of clean, fast, accurate tools that give you a direct answer and explain the reasoning behind it. No fluff, no friction.
All tools are built on formulas from peer-reviewed research and established health organizations like the WHO, NIH, and EFSA. We explain the limitations of every tool, because context matters as much as the number itself.
Every calculator on this site is built on established, peer-reviewed formulas. We don't invent numbers — we implement validated methods and explain exactly where they come from. For example, our calorie calculator uses the Mifflin-St Jeor equation (the most accurate BMR formula in current research), our protein calculator applies ranges from the International Society of Sports Nutrition, and our Zone 2 calculator uses the Karvonen heart rate reserve method.
Where formulas have meaningful limitations — and they all do — we explain them. A BMI calculator can't distinguish muscle from fat. A calorie calculator can't know your individual metabolic rate. An ideal weight formula was originally designed for medication dosing, not fitness goals. Being honest about what a tool can and can't tell you is as important as the calculation itself.
Nutrition calculators: Daily calorie and TDEE estimation, macro targets, protein needs for different goals and demographics (including women over 40), vitamin D requirements, and intermittent fasting schedules. These tools help translate nutrition research into actionable daily targets.
Fitness calculators: Heart rate zone training, Zone 2 calculator, calories burned by heart rate, one rep max estimator, running pace calculator, and body composition tools (BMI, body fat percentage, ideal weight). These support training decisions from beginner to intermediate level.
Lifestyle calculators: Sleep cycle calculator, water intake estimator, and related tools for recovery and daily health habits.
Blog: Evidence-based articles covering the topics our calculators address — from intermittent fasting to Zone 2 training to protein needs — written to explain the reasoning behind the numbers rather than just present them.
We try to reflect the actual state of research rather than defaulting to the most conservative guideline or the most popular claim. Where evidence is strong (protein for muscle maintenance, Zone 2 for aerobic base building, sleep cycles), we say so clearly. Where evidence is mixed or evolving (optimal macro ratios for fat loss, exact step count targets, morning vs evening exercise), we present the nuance honestly.
All content on this site carries a "not medical advice" disclaimer, because it isn't. These are tools for informed, healthy adults making everyday wellness decisions. They are not substitutes for clinical evaluation, and we don't pretend otherwise.
We're a small independent site. If you find our tools useful, sharing them with someone who needs them is the best way to support what we're building.
Some tools on this site include links to third-party products (primarily iHerb and select fitness apps) marked with a "Partner" label. If you click through and make a purchase, we may earn a small commission at no additional cost to you. These links help keep the site free. We only recommend products that are relevant to the tool's context — we do not accept payment to feature specific products.
From BMI to intermittent fasting — find the calculator you need.
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