Calculators that keep your numbers to yourself

Loan payments, mortgage costs, and BMI — computed instantly on your device. Nothing you type here is ever sent anywhere.

Calculators

Loan calculator

Work out the monthly payment and total cost of any fixed-rate loan — car, personal, or student. Read the guide →

Loan amount ($)

Interest rate (% APR)

Term (years)

Monthly payment—

Total interest—

Total repaid—

Mortgage calculator

Estimate your full monthly housing cost — principal & interest plus taxes, insurance, and HOA. Read the guide →

Home price ($)

Down payment ($)

Interest rate (% APR)

Term (years)

Property tax ($/year)

Home insurance ($/year)

HOA ($/month)

Monthly total—

Principal & interest—

Loan amount—

Total interest—

BMI calculator

Body mass index from your height and weight, with the healthy weight range for your height. Read the guide →

Height (cm)

Weight (kg)

Your BMI—

Category—

Healthy range for your height—

BMI is a screening measure, not a diagnosis — it doesn't account for muscle mass, age, or body composition. Talk to a healthcare provider about what's right for you.

Private by design, like every Toolsfully tool

These calculators are plain JavaScript running on this page. The numbers you enter — your loan size, your income assumptions, your weight — are processed in your browser's memory and never transmitted, logged, or stored. Refresh the page and they're gone.

The loan and mortgage calculators use the standard amortization formula for fixed-rate loans, so results match what banks and lenders quote for principal & interest. Actual mortgage offers add lender fees, PMI (usually required below 20% down), and rate variations — treat these numbers as a solid starting estimate, not a quote.