Compound Interest Tools

Worked examples

Compound Interest Examples

Use worked compound interest examples with direct calculator links for common amounts, rates, terms and monthly deposits.

Worked compound interest examples

These examples use monthly compounding and fixed annual rates. They are useful starting points for understanding how the same formula behaves with different amounts, rates, time periods and deposits.

ExampleFinal balanceInterest earnedCalculator
£1,000 at 5% for 10 years£1,647.01£647.01Open
£5,000 at 5% for 10 years£8,235.05£3,235.05Open
£10,000 at 5% for 10 years£16,470.09£6,470.09Open
£25,000 at 6% for 20 years£82,755.11£57,755.11Open
£50,000 at 4% for 15 years£91,015.08£41,015.08Open
£10,000 plus £250 monthly for 10 years£55,290.66£15,290.66Open
£0 plus £100 monthly for 20 years£41,103.37£17,103.37Open
£5,000 plus £100 monthly for 10 years£23,763.28£6,763.28Open

Example 1: £5,000 at 5% for 10 years

With monthly compounding, £5,000 at 5% for 10 years grows to approximately £8,235.05.

Example 2: £10,000 plus £250 per month

Adding monthly deposits changes the calculation. £10,000 plus £250 per month at 5% for 10 years grows to around £55,290.66.

Example 3: Starting from zero

Even without a starting amount, regular monthly deposits can compound. £100 per month at 5% for 20 years grows to about £41,103.37.

How to use these examples

Open the closest example in the calculator, then adjust the inputs to match your own scenario. You can change the currency symbol, compounding frequency, contribution timing, inflation adjustment, tax and fees.

Calculate it yourself

Use the free compound interest calculator to adjust the amount, rate, term, compounding frequency and regular deposits.

FAQ

Frequently asked questions

They are rounded educational estimates using monthly compounding and fixed rates. Real accounts or investments can differ because of fees, tax, variable rates or product rules.

Yes. Open any example in the calculator and adjust the amount, rate, term, deposits, currency or compounding frequency.

No. The examples below do not include tax or fees unless explicitly stated. The calculator has optional tax and fee inputs.

Start with the example closest to your situation, then adjust the inputs in the calculator.