It calculates monthly payment, total interest, total cost, remaining balance and amortization schedule. In property mode, it also includes purchase price, down payment, federal state, transfer tax, notary and land-register assumptions and optional broker fees.

A basic loan calculator often shows only the monthly payment. An amortization calculator shows how each payment is split between interest and principal and how the remaining balance falls over time. This calculator combines both.

For a fixed term, the calculator uses an annuity formula. For initial repayment mode, it uses the common mortgage approximation: loan amount times annual interest plus initial repayment rate, divided by 12.

The initial repayment rate is the principal repayment share in the first year, often 2% or more for German mortgages. As the balance falls, the interest share drops and the repayment share rises.

An extra payment reduces the outstanding balance on top of the regular monthly payment. Because future interest is calculated on a lower balance, more of later payments goes toward principal and the loan can finish earlier.

Property mode includes German real-estate transfer tax by federal state, notary and land-register assumptions and optional broker costs. Real costs can differ by contract and state, so the result is a planning estimate.

German real-estate transfer tax differs by federal state. A property in Bavaria can have a much lower transfer-tax burden than one in North Rhine-Westphalia or Schleswig-Holstein, which changes the equity need and loan amount.

No. It is a planning and comparison tool. Real mortgage terms depend on creditworthiness, property valuation, fixed-rate period, collateral, subsidies, lender margin and detailed contract costs.