Frequently Asked Questions
Common questions about our free health and fitness calculators.
Are these calculators free?
Yes. All calculators are 100% free with no account required.
How accurate are the results?
Our calculators use validated formulas (Mifflin-St Jeor for BMR, Navy Method for body fat, Devine/Robinson/Miller for ideal weight). Results are estimates and should not replace medical advice.
Do you store my data?
No. All calculations happen in your browser. We never transmit or store your personal measurements.
What units do you support?
All calculators support both metric (kg, cm) and imperial (lbs, ft/in) units with automatic conversion.
What is BMI?
BMI (Body Mass Index) is a screening tool that estimates whether your weight is in a healthy range for your height. A BMI under 18.5 is underweight, 18.5–24.9 is normal, 25–29.9 is overweight, and 30+ is obese.
What is BMR?
BMR (Basal Metabolic Rate) is the number of calories your body burns at rest to maintain basic functions. TDEE (Total Daily Energy Expenditure) adds your activity level on top.
How is body fat percentage calculated?
We use the US Navy circumference method, which requires waist, neck, and (for women) hip measurements along with height. It is an estimate; DEXA scans are more accurate.
What ideal weight formula should I use?
We provide Devine, Robinson, and Miller formulas — all are estimates. A healthy weight range is more useful than a single ideal number. Consult your doctor for personalised advice.