Free, no sign-up mortgage calculators for UK property buyers. All calculations run in your browser — nothing is stored or transmitted.
Calculate SDLT (England), LBTT (Scotland), or LTT (Wales) on any property purchase. Covers first-time buyer relief, second home surcharge, and all current tax bands as published by HMRC, Revenue Scotland, and the Welsh Revenue Authority.
Enter your loan amount, interest rate, and mortgage term to see your exact monthly payment and a full amortisation schedule showing how each payment splits between interest and capital.
Estimates your maximum borrowing based on income multiples (4× single, 4.5× joint) and models the lender stress test so you understand what your real ceiling looks like before you speak to a broker.
Shows how much interest you save and how many years come off your mortgage by making a fixed extra monthly payment. Includes a year-by-year comparison of standard vs overpayment schedules.
Works out whether switching to a lower rate makes financial sense once you account for early repayment charges and arrangement fees. Tells you the break-even month and total saving over the fixed term.
Enter your property value and outstanding balance to see your exact loan-to-value percentage and which lender rate band you fall into. Shows how much you would need to overpay to reach the next tier.
Mortgagemaths is an independent UK mortgage calculator. Tax bands are updated against official sources whenever rates change. Read our mortgage guides or learn more about the site.