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The monthly mortgage payment uses the standard amortization formula: M = P × [r(1+r)ⁿ] / [(1+r)ⁿ−1], where P is the principal (home price minus down payment), r is the monthly rate (annual rate ÷ 12), and n is the total payments (years × 12). This gives you the fixed monthly principal + interest payment.

According to the CDC and WHO, a BMI between 18.5 and 24.9 is considered healthy for most adults. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is obese. BMI is a screening tool — factors like muscle mass, age, and ethnicity affect interpretation.

Compound interest means you earn interest on your original principal AND on accumulated interest. For example, $10,000 invested at 7% annually grows to roughly $19,672 after 10 years with monthly compounding — nearly doubling without adding a single dollar. Starting early makes a massive difference.

It depends on your age, sex, height, weight, and activity level. Our calculator uses the Mifflin-St Jeor equation, the most research-validated formula available. The result is your TDEE (Total Daily Energy Expenditure). To lose ~1 lb per week, eat 500 calories below your maintenance number.

In the US, the standard is 15–20% of the pre-tax bill. 18% is increasingly considered the baseline, with 20%+ for excellent service. For delivery, 15–20% (minimum $3–5) is customary. For counter service, 10–15% is optional.

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