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Metabolic & weight-loss tools
Simple, transparent calculators that run entirely in your browser — nothing is sent anywhere or saved. Every result shows its math and the science it's anchored to. These are estimates, not medical or nutrition advice.
- Calories
Calorie Deficit & Protein Calculator
Estimate your daily calorie target for weight loss with the validated Mifflin-St Jeor equation, plus a protein range to protect muscle. Pick your sex, age, height, weight, activity, and goal.
Open calculator - Protein
Protein Target Calculator
Get a daily protein range (g/day) from your body weight, training, and goal — with a grams-per-meal target. Higher protein in a deficit helps preserve lean mass.
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Keep reading — the honest reviews
A number is the easy part; what you eat and which supplements (if any) actually help is the hard part. These evidence-led reviews are where to go next:
Disclaimer. These tools are informational and educational only — they are not medical or nutrition advice, not a diagnosis, and not a substitute for care from a licensed clinician or registered dietitian. They run entirely in your browser; no inputs are sent to a server or stored. Always verify important numbers with a professional before acting on them, especially if you are pregnant or breastfeeding, under 18, or have a chronic medical condition.