Investing calculators
Four independent free tools. Every calculation runs in your browser — your inputs in, arithmetic or model output back; none of it is a prediction or investment advice.
DCA calculator →
A fixed amount on a fixed schedule: backtest over real history (vs SPY), or project a plan from your own return assumption.
Options profit calculator →
At-expiration payoff chart, breakevens and max gain/loss for long calls/puts, covered calls, cash-secured puts and protective puts.
Option value calculator (Black-Scholes) →
Black-Scholes model value with Greeks (delta, gamma, theta, vega, rho); the risk-free rate prefills from the US Treasury yield curve.
Position size & risk calculator →
From your account size, per-trade risk (%) and entry/stop, get the whole-share size that keeps your worst case within budget, plus position value, actual risk and reward-to-risk; long or short.