PPolySim OS

Random Walk & Diffusion

Hundreds of walkers take random steps from a single point. The cloud spreads as the square root of time — diffusion, built from randomness.

Random Walk & DiffusionLive

Controls

Hundreds of walkers start at the center and step randomly. The cloud spreads as √(time) — the signature of diffusion.

Presets

▶ Run in Python

Data Inspector

Walkers400
Steps0
RMS distance0.0
Law⟨r²⟩ ∝ t

Governing equation

Reading this result: With 400 walkers the RMS distance grows as √(steps) — the defining signature of diffusion.

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

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How it works

Each walker steps in a random direction each frame. Individually unpredictable, collectively they obey a precise law: mean-squared displacement grows linearly with time (⟨r²⟩ ∝ t). This is the microscopic basis of Brownian motion, heat diffusion, and the diffusion equation.

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Frequently asked questions

Is this random walk simulation tool really free?
Yes. Random Walk & Diffusion runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
Can I save or share my simulation?
Create a free account to save projects, and use a shareable embed or minted DOI to publish a live, interactive version anywhere.
How accurate are the results?
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.