Free tools for index investors
Index investing is simple to explain and hard to sustain. What eats long-term returns is almost never the choice of index: it is the fees you never checked, the tax toll of a badly timed rebalance, and selling in the worst month of a drawdown.
These four tools take on one of those decisions each, and answer a single question. They are free, ask for no sign-up, and run in your browser: nothing you type leaves your device.
TER Calculator
What do my funds really cost me?
Works out the weighted average TER of your portfolio and projects, over 40 years, how many euros fees take away. Useful for choosing between two funds separated by a seemingly innocent 0.10%.
Open tool →DecisionIs it time to rebalance?
Do I act now or wait?
Four questions — drift, time since your last adjustment, tax cost and fees — and a verdict. Built for the moment you see your portfolio skewed and cannot tell whether the fix costs more than the problem.
Open tool →RiskCrash simulator
Could I actually sit through a drop like that?
Applies real historical crashes to your capital — the 2000 bubble (−49%), Lehman in 2008 (−56%), COVID in 2020 (−34%) — and estimates how long recovery would take, with and without contributions. It is a behavioural tool, not a forecast.
Open tool →AccountingAverage price calculator
What did I really pay for this?
Weighted average purchase price from your own transactions, counting sells, dividends and fees. For anyone who has been contributing for years and lost track of their real cost basis.
Open tool →Why free and with no sign-up?
Because a calculator that asks for your email before giving you a number is not a calculator, it is a form. None of these tools store what you type or send it to a server, and there is no paid tier behind them. If you want full portfolio tracking — your transaction ledger, live prices and the exact split of every contribution — that is the app, and it is free too.