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For Hobbyists & Makers · Monte Carlo (GBM)

Monte Carlo (GBM) for a dollar-cost-average plan

Built for hobbyists & makers exploring it for fun. Play with real physics and math, no license and no setup — just open and tinker. Simulate a dollar-cost-average plan live below — adjust the inputs and watch it respond, right in your browser.

Monte Carlo Price SimulationLive

Controls

Presets

Geometric Brownian motion models a price with constant drift and random volatility — the assumption behind Black-Scholes. Running hundreds of simulated paths reveals the full distribution of outcomes, not just an average. Educational tool, not investment advice.

▶ Run in Python

Data Inspector

Median outcome$0
5th percentile$0
95th percentile$0

Governing equation

Reading this result: Median outcome is about $0, just under the drift-only $107 — GBM compounds in log-space, so volatility always pulls the typical path below the average.

Runs locally in your browser — free forever. Scale to the cloud when reality gets heavy.

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More with Monte Carlo (GBM)

Frequently asked questions

Is this good for hobbyists & makers?
Yes — this version of "Monte Carlo (GBM) for a dollar-cost-average plan" is framed for hobbyists & makers exploring it for fun. Play with real physics and math, no license and no setup — just open and tinker.
Do I need to install anything?
No. It runs in any modern browser, free, with no account required.