Position size & risk calculator
Decide what you’re willing to lose on this one trade (a percent of the account), then enter your entry and stop-loss — the calculator returns the whole-share count that puts your worst case right at that budget, along with position value, the actual risk after rounding to whole shares, and (when you add a target) the reward-to-risk. It works long or short; for a long, it flags when the risk-based size costs more than your cash. Every number is a disclosed division of what you typed — not investment advice.
Ingresa tamaño de cuenta, % de riesgo, entrada y stop-loss para calcular.
El cálculo del tamaño de posición es aritmética sobre los números que ingresas: no es una recomendación de realizar ninguna operación ni asesoría de inversión. Supone que tu stop se ejecuta exactamente al precio del stop; las ejecuciones reales pueden deslizarse más allá, especialmente con gaps de precio.
How the sizing works
- Risk budget = account size × risk % — the dollars you’ve decided you can lose on this trade.
- Risk per share = |entry − stop| (entry − stop for a long, stop − entry for a short); a stop on the wrong side or equal to entry is flagged.
- Shares = floor(risk budget ÷ risk per share) — rounded down to whole shares, so the actual risk at that size is always ≤ the budget, never over.
- For a long on a cash basis: if shares × entry exceeds the account, it’s flagged with the max shares your cash can buy and the risk at that size (a short needs a margin account; this is a risk calc, not a margin check).
- Reward-to-risk = reward per share ÷ risk per share (when a target is set) — a ratio, not a probability of success and not a price forecast.