Private · editable assumptions · no sign-up
Free investing calculators that show their working
Explore a possible outcome, then change the return and fee assumptions to see how sensitive it is. The tools do not recommend an investment or predict what markets will do.
Monthly contributions and growth
Compound investment calculator
Change the starting amount, monthly contribution, time, return and fee assumptions. Compare the result without treating it as a forecast.
Model a scenario →Compare long-term fee drag
Investment fee calculator
Put two all-in annual fee assumptions against the same pot, contribution and return. See the pound difference compounding can create.
Compare two fee levels →Flat fee vs percentage fee
Platform fee comparison calculator
Compare two live tariff structures using a portfolio value, fixed and percentage charges, minimums, caps, dealing fees and fund costs.
Compare two platform tariffs →Use the tools in context
Numbers are the second step, not the first
Start with whether the money can stay invested and what the account or fund actually does. Then use a calculator to test costs and assumptions.