Free UK Mortgage Calculators
Four free calculators used by our advisers every day: monthly repayment, affordability, stamp duty and loan-to-value. Results are indicative — a full affordability assessment requires a lender application.
What each calculator does
- Mortgage repayment calculator — enter loan, rate and term to see monthly capital-and-interest repayments and total cost over the term.
- Affordability calculator — estimates a lender's likely maximum loan based on gross annual income and typical income multiples (usually 4.5×, sometimes up to 5.5× for higher earners or specific schemes).
- Stamp duty calculator — SDLT (England & NI), LBTT (Scotland) or LTT (Wales) at current bands, including first-time buyer relief and the additional-property surcharge.
- Loan-to-value (LTV) calculator — works out the LTV bracket your deposit or equity places you in, which drives the rate tier you qualify for.
How to use the results
These calculators use standard formulas and current UK tax bands. They do not run credit checks and do not access lender criteria — so they cannot tell you which specific product you will qualify for. Use them to size your budget, then speak to an adviser for a personalised assessment.
Frequently Asked Questions
Are the calculators free?
Yes, all four calculators are free to use with no sign-up.
Do the results guarantee a lender will lend that amount?
No. Lenders assess income, credit, expenditure and property. The affordability calculator is a starting-point estimate only.
Do you save my data?
The calculators run in your browser. Data is not stored unless you separately submit an enquiry form.
The Mortgage Genie Limited is an Appointed Representative of First Complete Limited, trading as Primis Mortgage Network, which is authorised and regulated by the Financial Conduct Authority. The Mortgage Genie FCA No 754691; First Complete (Primis) FCA No 435779.
Your home may be repossessed if you do not keep up repayments on your mortgage.