GCSE maths revision

Compound Interest Calculator

Start with the simple idea: £100 at 10% interest. Each year, the interest is added, then the next year’s interest is calculated on the new total.

Simple example

Imagine you start with £100 and earn 10% interest per year.

Year 1

£100 × 1.10 = £110

Year 2

£110 × 1.10 = £121

Shortcut formula

Final amount = starting amount × multiplieryears

£100 × 1.105 = £161.05

£100 at 10% for 5 years

Year 0£100.00
Year 1£110.00
Year 2£121.00
Year 3£133.10
Year 4£146.41
Year 5£161.05

Try it

Shortcut formula

Final amount = starting amount × multiplieryears

£100 × 1.10⁵ = £161.05

£161.05

That means £61.05 interest has been earned.

Year by year