1. Home
  2. Mortgages
  3. Mortgage Calculators
Published 07 June 2022

Mortgage Calculators

Our free online mortgage calculators are designed to help you work out how much you could borrow and what affects your repayments.

Use our mortgage calculators to estimate your mortgage repayments, stamp duty costs and more. Whether you’re a first-time buyer or remortgaging, our free easy-to-use calculators will give you an estimate within minutes. All we’ll need are a few details to get started.

Mortgage borrowing calculator

Get an instant estimate of much you can borrow to buy a home using our mortgage loan amount calculator.

Stamp duty calculator

Find out how much property tax you’ll need to pay for homes in England and Northern Ireland using our stamp duty calculator.

Mortgage repayment calculator

Get a quick estimate of your monthly mortgage repayments with our mortgage repayment calculator.

Mortgage overpayment calculator

Work out how much you could save on repayments by paying extra each month, using our mortgage overpayment calculator.

Buy-to-let mortgage calculator

Get an estimate of how much you could borrow for an investment property with our buy-to-let mortgage calculator.

Mortgage interest calculator

Use our mortgage interest rate calculator to estimate how much your repayments could change if interest rates fluctuate.


Compare Mortgages with Koodoo

Nerdwallet have partnered with Koodoo to provide mortgage comparisons from the UK’s leading providers.

Think carefully before securing other debts against your home. Your home may be repossessed if you do not keep up repayments on a loan or any other debt secured on it.

What is a mortgage calculator?

A mortgage calculator is a tool designed to help you estimate the cost of buying a home, such as mortgage repayments, how much you could borrow and stamp duty costs.

NerdWallet offers a range of calculators to help you quickly estimate different charges you may have to pay when buying a home.

Who is a mortgage calculator for?

A mortgage calculator may be used by anyone looking to purchase property including:

What information do I need to use a calculator?

The information you’ll need may vary depending on the calculator you use, but most will ask for the following details:

How much can I afford to borrow?

How much you could borrow to buy a house will depend on several factors. Each lender has its own criteria for deciding how much to lend you, but alongside your income, they will consider your expenses and employment status.

The amount you can put down for a house deposit will also affect how much you’ll be able to borrow. Lenders ask for a minimum deposit of 5% of a property’s value if you are buying without a guarantor. Larger deposits usually give you access to better mortgage deals with lower interest rates.

Our mortgage calculator can give you an idea of what you may be able to borrow to buy a home.

How is my affordability assessed?

Mortgage lenders look at your debt-to-income ratio (DTI) when assessing whether you can afford a mortgage. A DTI compares the total debt repayments you make each month to your monthly income.

You can calculate your DTI by first adding up your existing monthly repayments, such as credit cards, loans and car finance. Next, add up your monthly income including wages, benefits and pension income. Finally, divide your monthly debt repayments by your monthly income and multiple this number by 100.

For example, if your debt repayment costs you £500 per month and your monthly income is £2,000, your DTI would be 25%.

A debt-to-income ratio of 29% or less is usually considered good by most lenders. However, whilst this ratio varies amongst lenders (and is not the only way they assess your affordability) higher debt to income ratios may suggest more risk to lenders which may affect how much you’ll be able to borrow.

Which mortgage calculator is right for me?

The best mortgage calculator for you will depend on the specific cost you would like to estimate. Our ‘how much could I borrow calculator’ could be a great place to start as it gives an idea of the size of mortgage you might be able to get.

How much deposit do I need to buy a house?

There isn’t a set amount you need to save for a deposit to buy a house. Typically lenders ask for a minimum deposit of 5% of a property’s value, but larger deposits can potentially give you access to lower interest rates and better mortgage deals. Our mortgage deposit calculator can quickly help you estimate the size of the deposit you’ll need to buy a home.

What are mortgage interest rates?

Mortgage interest is money paid to a lender in return for borrowing from them. It’s usually paid as a percentage of the total amount of money you borrow for a mortgage. Mortgage interest rates are set by lenders but are likely to be affected by the interest rate set by the Bank of England known as The Base Rate

There are three main types of mortgage interest rates:

Where can I find the best mortgage deals for me?

Shopping around can help you find the best mortgage offers. Price comparison sites can be a great place to start and can help you find and compare a number of mortgages quickly. If you’re a first-time buyer or would like expert advice during the mortgage process, speaking to an independent mortgage adviser can also help you find the best deals for your financial circumstances.

About the Authors

John Ellmore

John Ellmore was a director at NerdWallet UK and a company spokesperson for consumer finance issues and he was committed to providing clear, accurate and transparent financial information.

Read More
Brean Horne

Brean was a writer and spokesperson for NerdWallet who covered a variety of topics including money-saving tips, credit scores and managing debt. With over five years' experience in finance, she…

Read More
Dive even deeper
Could April Mortgage Rates Fall Again?

Could April Mortgage Rates Fall Again?

Fixed-rate mortgages look like they could continue to drop, while inflation expectations and threat of a banking crisis have the potential to halt Bank of England base rate rises.

March Mortgage Rates May Have Room to Fall Further

March Mortgage Rates May Have Room to Fall Further

Fixed-rate mortgages could head lower, but a further Bank of England base rate increase could see variable rate mortgages rise again. Read on to find out mortgage rate predictions for March.

How I Bought My First Home In South East London

How I Bought My First Home In South East London

From saving up a deposit to finding the perfect home in South East London, we follow a recent first-time buyer in our My First Home series.

Back To Top