Making science-backed nutrition calculations free for everyone
MacrosMeasure was built on a simple belief: every person — regardless of budget, background, or access to a dietitian — deserves accurate, formula-transparent nutrition data. We built 18 free calculators grounded in peer-reviewed science so you never have to guess.
Most nutrition calculators on the internet have at least one fatal flaw: they're paywalled, riddled with intrusive ads, built on inaccurate formulas with no cited sources, or they demand account creation just to see a calorie estimate. We've experienced all of this firsthand — and it's frustrating.
MacrosMeasure exists to fix that. Every tool on this site was hand-built with three non-negotiables: accuracy (every formula references a peer-reviewed source), transparency (you can read the science behind every result), and accessibility (no signup, no subscription, no paywall — ever).
Whether you're a first-time dieter trying to understand your calorie needs, a competitive athlete tracking macros to the gram, or a fitness coach building plans for clients, MacrosMeasure gives you the same science-backed data that nutritionists use — for free.
Every MacrosMeasure calculator is built on named, peer-reviewed formulas — not proprietary algorithms. Below is a plain-English explanation of each one, with links to the original research.
The Mifflin-St Jeor equation, published in 1990, is the most widely validated formula for estimating Basal Metabolic Rate (BMR). It accounts for sex, weight, height, and age, and consistently outperforms older equations like Harris-Benedict in clinical accuracy studies. We multiply BMR by an activity factor (1.2–1.9) to produce your Total Daily Energy Expenditure (TDEE).
Developed by the United States Navy and validated by Hodgdon & Beckett (1984), this formula estimates body fat percentage from circumference measurements — neck, waist, and hips (women only). While not as precise as DEXA scans, it offers excellent accuracy for the average person without any equipment beyond a tape measure.
Bryan Epley published this formula in 1985 for estimating your one-rep maximum (1RM) from a submaximal lift. It remains one of the most widely cited formulas in strength and conditioning literature. Our implementation lets you input any rep count (1–12) and weight to estimate your theoretical maximum lift for any exercise.
Our recipe nutrition analyser draws from the USDA FoodData Central database — the most comprehensive, publicly available nutrient database in the world, containing over 300,000 foods and ingredients. Data is maintained by the U.S. Department of Agriculture and updated quarterly.
To calculate energy expenditure during exercise, we use Metabolic Equivalent of Task (MET) values aligned with the American College of Sports Medicine (ACSM) guidelines and the Compendium of Physical Activities. Each activity has an established MET value; multiplied by body weight and duration, this gives a reliable calorie burn estimate.
A note on individual variation: All formulas produce population-level estimates. Genetics, hormones, gut microbiome composition, sleep quality, and medication can cause individual results to deviate from these predictions by ±10–15%. Our calculators provide an evidence-based starting point — not a clinically measured result.
[YOUR_BACKGROUND] — a developer and health-fitness enthusiast with hands-on experience tracking nutrition for [X] years. After growing frustrated with inaccurate, paywalled, and privacy-invasive nutrition apps, the decision was made to build something better: a completely free, formula-transparent alternative that treats users as intelligent adults.
Every calculator on MacrosMeasure has been personally tested with real inputs against published research papers to ensure the outputs are consistent with what a registered dietitian would calculate manually.
All calculators are cross-validated against peer-reviewed nutritional science before publishing. Each formula result is compared manually against published reference tables and clinical calculators to verify accuracy within accepted error margins.
MacrosMeasure calculators are reviewed for formula accuracy, not for clinical medical outcomes. Results are mathematical estimates and should not replace the advice of a registered dietitian (RD) or licensed physician.
These four commitments are permanent. Not marketing copy — actual constraints built into how this site operates.
Your inputs never leave your browser. We do not collect, store, or monetise any health or biometric information you enter into our calculators.
Every tool is fully functional without an account. No email, no password, no profile. Just open the page and calculate.
MacrosMeasure provides mathematical estimates based on established formulas. We are not a medical service and our results are not prescriptions.
Every formula we use is publicly cited. You can read the original research papers yourself. No proprietary scoring systems, no mystery numbers.
The results produced by MacrosMeasure calculators — including calorie targets, macro ratios, BMI classifications, body fat estimates, and weight recommendations — are mathematical estimates derived from population-based research formulas. They are provided for general informational and educational purposes only.
MacrosMeasure is not a medical service and does not provide medical, dietary, or clinical advice. The information on this website is not intended to diagnose, treat, cure, or prevent any disease or health condition.
Always consult a qualified physician, registered dietitian (RD), or licensed healthcare provider before making significant changes to your diet, exercise routine, or supplement regimen — particularly if you have a pre-existing health condition, are pregnant or nursing, or are under the care of a medical professional.
Do not disregard or delay seeking professional medical advice because of information you found on this website.
For full details, see our Disclaimer, Privacy Policy, and Terms of Service.
Have a question about our methodology, found a calculation that looks off, or want to suggest a new calculator? We read every message and take formula feedback seriously.
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