Medical disclaimer

Formula-based estimates

Every number on this site is produced by a published prediction equation applied to the values you typed. Nothing is measured. Prediction equations typically land within roughly 5 to 10 per cent of measured resting energy expenditure, and the activity multiplier adds further uncertainty on top of that. Two people with identical inputs can have genuinely different energy requirements.

Individual variation

Body composition, thyroid and other hormonal function, medication, sleep, stress, illness, recovery status, non-exercise movement, ageing and adaptation to a change in intake all shift energy needs in ways no calculator can see.

Not a diagnostic tool

Nothing here diagnoses, treats, cures or prevents any condition, and no output describes the state of your metabolism. BMI in particular is a population screening measure: it cannot see body-fat percentage, muscle mass, fat distribution, bone density, fitness or metabolic health.

Not a substitute for professional care

This site does not replace consultation with a qualified clinician or registered dietitian, and it must not be used in an emergency. If you feel unwell, call your local emergency number or your doctor.

Where extra individual guidance is needed

• Pregnancy and breastfeeding — energy and nutrient needs differ and should be set with a clinician.
• A current or past eating disorder, or a difficult relationship with food, tracking or the scale.
• Any medical condition affecting nutrition, digestion, kidney or liver function, or blood sugar.
• Medication that changes appetite, fluid balance or body weight.
• Children and adolescents — adult BMI categories and adult equations do not apply; paediatric growth references and clinical supervision are required.
• Adults over roughly 70, athletes at very high training loads, and people at the extremes of body size, where prediction equations lose accuracy.

No guaranteed outcome

No result promises or guarantees weight loss, weight gain, a body composition change or any health outcome, at any pace. We do not publish an ideal weight, an exact calorie requirement or a personalised medical plan.

Questions or corrections

Tell us if something here reads as advice rather than education — contact us and we will fix it. See also our methodology and terms of use.