Mortgage calculators and tools

Use mortgage calculators to pressure-test the figures behind your next move. Whether you’re working out what you can borrow, planning your deposit, estimating Stamp Duty, or checking loan-to-value, these tools are designed to give you a clearer starting point.

How much can I borrow?

An affordability calculator helps you estimate the home price you may be able to consider and the kind of monthly payment that could follow. It’s useful for narrowing down options before you speak to a broker or start comparing deals.

Save for the mortgage deposit

A deposit calculator can help you model how much you might need to save and how long it could take to reach your target. It’s a practical way to see how different deposit amounts could affect the mortgage you’d be looking for.

How much is Stamp Duty?

Stamp Duty Land Tax (SDLT) can be one of the larger upfront costs when buying a property. A Stamp Duty calculator helps you estimate the likely tax due, supporting budgeting for the purchase.

Loan-to-value (LTV)

Loan-to-value is the relationship between the mortgage amount and the property value. An LTV calculator helps you understand the percentage you’re borrowing, which can be a helpful reference point when you’re thinking about mortgage options.

Looking to remortgage

If you’re considering switching your mortgage, a remortgage calculator can be used to estimate how monthly repayments might change under different scenarios. It’s best used as a planning tool rather than a definitive quote.

Start with a mortgage in principle

A mortgage in principle calculator can help you get an early indication of what a lender may consider. It can support early planning, but it’s not the same as a full mortgage offer and will depend on the details of your application.

About mortgage calculators

What is a mortgage calculator?

Mortgage calculators are digital tools that estimate key figures across different parts of the buying and mortgage journey. They can help you model affordability, deposit requirements, Stamp Duty, loan-to-value, and repayment scenarios—so you can make more informed decisions about what to explore next.

What information do I need to use them?

Most calculators ask for a small set of inputs such as property price, deposit, mortgage term, and income-related figures (where relevant). The output is an estimate intended to support planning.

How accurate are the results?

Calculator results are indicative. Lenders assess applications using a wider range of factors, and the final mortgage terms you may be offered can vary. Use these tools to understand the direction of travel and to prepare better questions for your broker.

How is a mortgage calculated?

Mortgage repayments are influenced by the amount borrowed, the term, the interest rate, and the repayment type. In general, repayment mortgages combine paying down the loan balance with paying interest, while interest-only mortgages pay the interest and leave the capital balance unchanged.

Using the calculators together

Many home buyers find it helpful to work through the numbers in sequence:

• Estimate affordability to understand a realistic purchase range
• Plan a deposit target and timeline
• Check Stamp Duty to budget for upfront costs
• Use loan-to-value to understand how much you’d be borrowing relative to the property
• If relevant, model remortgage scenarios or early borrowing expectations

These tools are designed to help you build a clearer picture before you compare options and discuss your circumstances with a mortgage professional.