UK Savings & Investment Calculators

Saving works best when you can see the effect of interest and inflation over time. These calculators help you plan a target, understand how your money grows, and work out what you might owe in tax on interest.

Savings and compound interest

The savings calculator shows how a lump sum and regular deposits grow, and the compound-interest guide explains why money grows faster as interest is reinvested. The future-value calculator projects a single amount forward over a set number of years.

ISAs

Cash ISAs let you earn interest tax-free up to your annual allowance. The ISA calculator shows how a regular or lump-sum ISA contribution could grow over time, and the what-is-an-ISA guide explains the rules.

Emergency fund

An emergency fund is a cash cushion for unexpected costs. The emergency-fund calculator suggests a target based on your monthly spending, and the building-an-emergency-fund guide walks through how to get there.

Inflation

Inflation reduces what your money can buy. The inflation calculator shows what a sum today would be worth in the future (or what something cost in the past), which is a reminder that cash sitting still can lose value in real terms.

Tax on savings interest

Interest you earn may be taxable, depending on your income and the personal savings allowance. The savings-interest-tax calculator estimates what you'd owe.

Frequently asked questions

How much should I save each month?

A common target is to build an emergency fund of three to six months of essential spending, then save a set percentage of your income. The how-much-should-i-save guide has more detail.

Is interest on savings taxable?

It can be, depending on your income and your personal savings allowance. Cash ISAs pay interest tax-free up to your allowance.