How do I simulate a heartbeat?

Open this page and use the live SIR Epidemic tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.

Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.

Can I use my own numbers?

Absolutely — every input is adjustable, and with data import you can drive a heartbeat from your own measurements.

Use case · powered by SIR Epidemic

SIR Epidemic for a heartbeat

Simulate a heartbeat live in your browser. This runs the real SIR Epidemic solver — adjust the inputs, watch it respond instantly, and export the result. No install, no account.

For:Students Researchers Educators Engineers Hobbyists & Makers K-12 Students First Responders

SIR Epidemic ModelLive

compartmental disease dynamics

Controls

Presets

Basic reproduction R₀

Infectious period (days)

Initial immune (vaccinated)

The SIR model splits a population into Susceptible, Infected, and Recovered and lets them flow between compartments. R₀ — the average number infected by one case — sets whether an outbreak grows. Vaccinating above the herd-immunity threshold 1−1/R₀ prevents an epidemic outright.

▶ Run in Python

Data Inspector

Peak infected0.0%

Total infected0.0%

Herd immunity60%

Governing equation

\frac{d S}{d t} = - β S I, \frac{d I}{d t} = β S I - γ I, \frac{d R}{d t} = γ I; β = 0.357, γ = 0.143, R_{0} = \frac{β}{γ} = 2.50

Reading this result: R₀ = 2.50 > 1 with only 0% immune, so infections grow into an epidemic. You would need to immunize 60% (the herd-immunity threshold 1−1/R₀) to stop it; the current effective reproduction number is 2.50.

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

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About this simulation

The full SIR Epidemic tool models a heartbeat with the same numerics engineers and scientists use — running entirely client-side. Change any parameter and the result updates in real time, so you can build intuition, check a design, or teach the concept without spreadsheets or installs.

More you can do with SIR Epidemic

SIR Epidemic for a bacterial growth SIR Epidemic for a predator-prey cycle SIR Epidemic for a neuron firing SIR Epidemic for a virus spread SIR Epidemic for a gene expression SIR Epidemic for a protein fold SIR Epidemic for a muscle contraction SIR Epidemic for a blood flow

Other ways to simulate a heartbeat

Dynamical Systems for a heartbeat Epidemic Network for a heartbeat Spatial Predator–Prey for a heartbeat Hodgkin-Huxley Neuron for a heartbeat Lotka-Volterra for a heartbeat Hardy-Weinberg for a heartbeat

Frequently asked questions

How do I simulate a heartbeat?: Open this page and use the live SIR Epidemic tool below — set your inputs and the simulation runs instantly in your browser using real numerics. No install, no account needed.
Is it free?: Yes. The simulation runs free in your browser. A one-time unlock or a Pro plan adds advanced parameters, saved presets, data import, and clean exports.
Can I use my own numbers?: Absolutely — every input is adjustable, and with data import you can drive a heartbeat from your own measurements.