Calorie Calculator

Estimate your maintenance calories plus bulking and cutting targets using the Mifflin-St Jeor equation.

How to Use These Numbers

This is a rough adult estimate, not an individualized diet or deficit. The formula cannot assess growth, pregnancy, illness or eating disorders. A qualified healthcare professional or dietitian can help evaluate nutrition needs. No automatic bulking or cutting prescription is provided.

Not medically reviewed. IronPeak publishes general editorial education, not medical advice, a diagnosis, a prescription, or individualized clearance. No clinician reviewer or professional credentials have been verified for this site. Review & sourcing policy.

Calorie and protein estimates are for adults 18+ only; adult BMI categories are for ages 20+. These tools do not assess growing athletes, pregnancy, illness or eating disorders. Consult a qualified healthcare professional or registered dietitian for individual guidance.

Sources & Evidence Limits

NIH ODS summarizes ingredient research, not evidence that a particular branded product works or is safe for you. Many ingredients and blends have limited or mixed evidence.

NIH Office of Dietary Supplements: Exercise and Athletic Performance (consumer fact sheet) — Adult ingredient evidence, variable benefits, limited evidence for many ingredients, interactions, and caution for minors.
FDA: Questions and Answers on Dietary Supplements — No FDA premarket approval; manufacturer responsibilities; speak with a health professional before purchase or use.
American Academy of Pediatrics / HealthyChildren: Performance-Enhancing Sports Supplements: Information for Parents — Food, fluids, training and rest first; no demonstrated performance benefit of protein or creatine supplements in younger athletes; stimulant and contamination concerns.

Sources retrieved October 9, 2026. No clinician has reviewed this content. Read our sourcing policy.