Each calculator below does one job, so this page explains what that job is before you open it. Everything runs in your browser, is free to use, and is for information only — none of it is financial advice.
Calculators marked Experimental are still under development, so treat their figures as rough illustrations. Full assumptions and data sources are listed on each calculator's own page, and the terms of use apply throughout.
Start here if you want to understand how the value of money changes over time.
Best for: sense-checking savings goals and long-term retirement targets.
Enter an amount, a number of years, and an average inflation rate to see how much buying power that money keeps — and how much you would need in future to buy the same things.
For projecting how a pot could grow with interest, regular deposits, and optional withdrawals.
Best for: comparing easy-access, ISA, and regular-saver pots on one screen.
Enter a starting balance, an interest rate, and a term to see the projected balance. Add weekly, monthly, or yearly deposits, optional withdrawals, and yearly increases, then review the figures, table, and chart.
For a remaining repayment mortgage balance, when you want the monthly payment or how long is left.
Best for: checking a remaining repayment mortgage, or seeing how a different monthly payment would change the term.
Enter the remaining amount, the interest rate, and the years and months left to see the level monthly payment. Add an optional yearly overpayment, or swap those last two fields around to enter a monthly payment instead and see how long it would take to clear the balance.
Three tools for UK government bonds, all using the Debt Management Office list of conventional gilts with refreshed clean prices. Each one assumes you buy now and hold to redemption at £100.
Experimental
Best for: checking the detail of a single gilt you are considering.
Looks at one gilt in detail. Choose a gilt and a quantity, and it estimates every coupon payment through to redemption, the tax due on that income, and what you actually end up with.
Experimental
Best for: narrowing a bracket of gilts down to a shortlist.
Compares every gilt in a maturity bracket at once for your tax band, so you can see which ones look better value before drilling into one of them.
Experimental
Best for: planning a fixed number of retirement years with known cashflows.
Splits one starting pot across gilts that mature in consecutive years, so cash arrives from coupons and redemptions in each year you plan to spend it.
For working out what your pension pots could pay you, and for how long.
Experimental
Best for: testing whether a retirement income target is realistic.
Answer a short set of questions and it projects drawdown from your taxable and tax-free pots at your target income, showing when the money is likely to run out.