Saving & investing

Investment Growth Calculator

Investment returns are uncertain, so this calculator is most useful as a scenario tool rather than a forecast. Try several return assumptions instead of relying on one number.

Free calculatorInputs saved only in this browser

Investment plan

Model a scenario rather than a guaranteed return.

£
£/month
%
%
Platform, fund and advice fees if applicable.
%
Used only to show an indicative real value.
years
£

Your estimate

Use the result as a planning guide and change inputs to test the assumptions that matter most.

How this calculator works

Expected annual return is reduced by the annual fee assumption before monthly compounding. Inflation is then used to express the projected pot in approximate today-money terms.

How to use it

  1. Enter your current investment balance and monthly contribution.
  2. Choose an expected annual return and time horizon.
  3. Add annual platform/fund fees.
  4. Add an inflation assumption if you want a real-value comparison.
  5. Use the target field to see the contribution needed under the same assumptions.

Assumptions and limitations

Investment values can fall as well as rise and returns are not smooth. Tax, market volatility, contribution timing and product rules are simplified or excluded.