Evidence hierarchy
- Consensus statements and systematic reviews from recognized scientific or professional organizations.
- Peer-reviewed randomized trials and well-designed observational research.
- Government or academy reference intakes and safety opinions.
- Manufacturer information only for factual product details—not efficacy claims.
Formula design
We prefer practical ranges over decimal-level precision. When research provides a weight-based range, the calculator preserves that range. When evidence does not establish a supplement-specific equation—as with water intake “required” by creatine—we use a general estimate and label it clearly.
What we do not do
- Diagnose conditions or personalize treatment.
- Invent formulas from search trends.
- Hide uncertainty to make a tool look more authoritative.
- Allow affiliate commission to alter a calculation.
Review and correction policy
Pages include a reviewed date and direct source links. Formula changes require an update to the explanatory copy and reviewed date. Readers can report an error at [email protected]. Clear factual or calculation errors are corrected promptly; disputed interpretations are checked against the strongest available evidence.
Medical boundary
The calculators are educational estimates for generally healthy adults. They do not replace care from a qualified professional. Pregnancy, adolescence, kidney or cardiovascular disease, medication, eating disorders and prescribed fluid or nutrient restrictions require individualized guidance.
Policy published and reviewed: August 16, 2026.