24/7 UK Mortgage Calculator
A growing library of free UK calculators for mortgages, savings, pay and tax, budgeting and debt.
Twelve calculators across four categories, each with a plain-English explanation of how it works and what it assumes. No sign-up, no personal details — just your numbers and a clear answer.
Calculators
Free UK calculators for mortgages, savings and interest, income and tax, and budgeting and debt.
Mortgage Calculators
See how your mortgage balance and interest could change over time, and estimate when it may be repaid.
Use calculator → Overpayment Calculator
See how monthly or lump-sum overpayments could reduce your mortgage term and total interest.
Use calculator → Affordability Calculator
Get an indicative estimate of how much you could borrow, based on your income and deposit — not a lending decision or approval.
Use calculator →Savings & Interest
Project how regular deposits and compound interest could grow your savings, with a year-by-year breakdown.
Use calculator → Savings Goal Calculator
Work out the monthly saving needed to reach a target by a set date, and how the interest rate changes it.
Use calculator → Fixed-Rate Savings Calculator
Estimate the interest and maturity value of a fixed-term bond, and compare how different interest arrangements pay out.
Use calculator →Income & Tax
Estimate pay after Income Tax, National Insurance, pension and student loan for 2026/27 or 2025/26, including Scottish rates.
Use calculator → Salary Increase Calculator
See how much of a pay rise you’d actually keep once tax, National Insurance, pension and student loan are taken off.
Use calculator → Hourly Wage to Salary Calculator
Convert an hourly rate into weekly, monthly and annual gross pay, including overtime and unpaid weeks.
Use calculator →Budgeting & Debt
Add up income, bills and savings to see what’s left each month. Nothing you enter is stored or sent.
Use calculator → Debt Repayment Calculator
Find out when a debt will be cleared, what it will cost in interest, and what paying a little extra would save.
Use calculator → Debt Snowball vs Avalanche Calculator
Compare paying off several debts smallest-balance-first or highest-rate-first, with a month-by-month plan.
Use calculator →Articles & Guides
One guide so far, with more planned as the site grows.
About this site
24/7 UK Mortgage Calculator is a free, independent set of UK money calculators — no sign-up required, and the figures you enter never leave your browser. Every result is an estimate for general guidance only, not financial advice. Each calculator explains its method and assumptions, and the tax calculators state which tax years they support and link to the official GOV.UK figures they use.