Money math
Three small calculators. Put in your own numbers and see what they add up to.
What trading costs take
Every trade pays a spread, a fee, or slippage. This shows how those small amounts stack up over many trades.
How this is worked out: each trade changes the balance by position size × (gain − cost), compounded over every trade. Real results vary trade to trade; this uses one average.
What a fund fee takes
An annual fee looks small as a percentage. Over years it compounds, just like returns do.
How this is worked out: monthly compounding at (return − fee) ÷ 12, with contributions added at the end of each month. Taxes and inflation are not included.
How long savings last
If your income dropped, how many months would your savings cover?
How this is worked out: savings ÷ (expenses − income). It assumes both stay flat and savings earn no interest.