Same trade, six rulebooks for how much to buy.

Set capital, entry and stop once, then switch method below to watch the position size change — Fixed Amount, Fixed Fractional, Volatility (ATR), Kelly Criterion, Fixed Ratio and Martingale, each worked out step by step so it is never a black box. This tool is free and does not require an account.

Same capital, same entry, same stop — six different position sizes. Kelly and Fixed Ratio don't size from your stop at all, so their risk column is what your stop would imply, not what the method targets. The highlighted row is whichever method is open above.

Educational tool, not investment advice. Position sizing rules shown here are commonly discussed frameworks (see Quantified Strategies for further reading); Martingale and Anti-Martingale are gambling-derived staking systems included for completeness, not recommended for investing. *Risk figures assume a full exit at the stop-loss price with no slippage.