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Stochastic Learning StudioBeta
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Connected Guides
  • Monte Carlo option pricing
  • Geometric Brownian motion

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Monte Carlo Pricing

Price a European call by simulation; the running estimate converges to the analytic Black–Scholes price.

Parameters

100
10300
100
10300
1.00
0.253
3.0%
00.1
20.0%
0.050.6
5000
20020000
7
1100
Metrics
MC estimate
9.202
Black–Scholes price
9.413
Standard error
0.201
Convergence to the Black–Scholes price

95% confidence band (±1.96·SE)

MC estimateBlack–Scholes
Distribution of S_T and the paths

Select bins in the histogram (click or drag) to highlight the paths that ended there. Esc clears.

Path-dependent payoffs on the same paths

All four payoffs are evaluated on the same simulated paths (50 monitoring dates), so their differences come from the payoffs, not from sampling noise.

Drag the barrier B (or focus it and use the arrow keys). A path that touches it is knocked out: it turns grey from that moment and pays nothing.

Up-and-out call · MC price ± 1.96·SE
3.556 ± 0.178
European (Black–Scholes)
9.413
Paths knocked out
17.3%
Continuous monitoring (closed form)
3.203
Price against the barrier level
Up-and-out callEuropean (Black–Scholes)

Moving the barrier up raises the price from zero towards the European price. Discrete monitoring (50 dates) is slightly dearer than the continuous closed form, because it misses crossings between dates.

About this tool

Monte Carlo simulation prices an option by averaging its discounted payoff over many simulated outcomes. This tool simulates terminal stock prices under risk-neutral geometric Brownian motion and shows the estimate and its confidence interval converging towards the Black–Scholes price as the number of paths grows.

Frequently asked questions

How fast does a Monte Carlo estimate converge?

The standard error falls like 1/√N: four times as many simulations halve the error.

Why use Monte Carlo if Black–Scholes has a formula?

Here the formula is the benchmark that shows the method works. Monte Carlo becomes essential for path-dependent payoffs, many underlyings and models without closed-form prices.