Mortgage Calculator

A mortgage is usually the largest financial commitment a household ever makes, and the monthly payment is only part of the story. Two loans with the same monthly figure can differ by tens of thousands over their lifetime because of the term and the interest rate behind them. This calculator shows the monthly repayment for a given amount, rate and term, together with the total interest you would pay across the whole loan.

Seeing total interest changes how people shop. Extending a term from twenty-five to thirty-five years lowers the monthly payment attractively, but the extra decade of interest can dwarf the saving. Conversely, a rate difference that looks trivial as a percentage becomes a large number when multiplied by a six-figure balance over decades, which is what makes it worth negotiating.

Use the calculator to model scenarios before you speak to a lender: a larger deposit, a shorter term, a rate half a point higher in case the market moves. Remember that the figure produced covers principal and interest only. Property taxes, buildings insurance, service charges and mortgage insurance are additional and vary by location.

How to use the Mortgage Calculator

1. Enter the loan amount, which is the purchase price minus your deposit.
2. Enter the annual interest rate offered, as a percentage.
3. Set the term in years, typically between fifteen and thirty-five.
4. Read the monthly repayment and the total interest across the full term.
5. Change one input at a time to see which lever actually moves the outcome.

Examples

• A first-time buyer compares a 25-year and a 30-year term on the same loan and sees the extra lifetime interest before choosing.
• A homeowner considering remortgaging checks how much a rate drop of 0.75 points would save each month.
• A couple deciding whether to put an extra sum into the deposit models the effect on both payment and total interest.

Frequently asked questions

Does the result include taxes and insurance?

No. It shows principal and interest only. Add property tax, insurance and any service or association charges to estimate your true monthly housing cost.

What formula is used?

The standard amortising loan formula, which assumes a fixed rate and equal monthly payments over the full term.

How do overpayments change things?

Any overpayment reduces the principal, so subsequent interest is charged on a smaller balance. Even modest regular overpayments can remove years from a term, subject to your lender's rules.

Is this a formal quotation?

No. It is an estimate for planning. Only a lender can issue binding figures after assessing your circumstances.

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