What these calculators are for
Every serious trading plan comes down to a handful of sums: how big to trade, what a stop costs, whether the numbers add up to an edge, and how close you are to a rule that ends the account. Doing them by hand before each trade is slow, and doing them in your head is how a position ends up three times too large.
Each calculator here answers one of those questions and shows the answer as a picture: the trade on a price axis, the size against the stop distance, a spread of simulated outcomes, the floor under a funded account. The pictures make the sensitivity visible. You see at once what a wider stop or a lower win rate does.
How the calculators work
The sums are the standard ones: fixed fractional position sizing, pip arithmetic, expectancy from win rate and payoff, gambler's ruin and Monte Carlo simulation. Each page states its formula and works one example with the same numbers the calculator opens with, so you can check the arithmetic yourself.
Everything runs in your browser. Nothing you type is sent to a server, and the address bar updates with your inputs so you can share an exact calculation as a link. The simulations use a fixed random seed, so the same inputs always give the same picture.
Where the numbers stop
A calculator knows your inputs and nothing else. It does not know about gaps, slippage, spreads that widen at the news, your broker's margin rules or a prop firm's fine print. Use the results as a plan, then check them against your platform and your firm's current rules. Nothing on these pages is investment advice, and trading leveraged products carries a high risk of loss.
Frequently asked questions
Are the trading calculators free?
Yes. Every calculator is free to use, with no account, no email and no limit on how many calculations you run.
Do I need to sign up to use them?
No. They work for anyone who opens the page. A SetupBook account is only needed if you want your own trades analysed automatically.
Is my data stored or sent anywhere?
No. The numbers you type stay in your browser. The only trace is the address bar, which holds your inputs so you can copy a link to the exact calculation.
Which calculator should I start with?
Start with the position size calculator if you are deciding how much to trade, and the expectancy calculator if you want to know whether your results add up to an edge. Prop-firm traders can go straight to the drawdown calculator.
How accurate are the results?
The arithmetic is exact for the inputs you give. Real trades differ from the plan because of slippage, spreads, fees and gaps, so treat each result as the limit your plan allows, not as a guarantee.
Can I use them for forex, stocks, crypto and futures?
Yes. The position size calculator works for any instrument with a multiplier, and the forex pages know pips and lots. The statistics calculators work on any series of trades.