How do I simulate a laser beam?

Open this page and use the live Snell's Law 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 laser beam from your own measurements.

Use case · powered by Snell's Law

Snell's Law for a laser beam

Simulate a laser beam live in your browser. This runs the real Snell's Law 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

Snell's Law — RefractionLive

n₁ sin θ₁ = n₂ sin θ₂

Controls

Light bends when it crosses between media. Going into a slower medium it bends toward the normal; going the other way past the critical angle it reflects entirely.

Presets

Incidence angle

Index n₁ (top)

Index n₂ (bottom)

▶ Run in Python

Data Inspector

n₁ → n₂1 → 1.5

Critical anglen/a

Snelln₁sinθ₁ = n₂sinθ₂

Governing equation

n_{1} sin θ_{1} = n_{2} sin θ_{2} : 1 sin 4 0^{\circ} = 1.5 sin θ_{2}, θ_{c} = arcsin \frac{n _{2}}{n _{1}} = n/a

Reading this result: Into a denser, slower medium: the ray bends toward the normal, so the refracted angle is smaller than the incidence angle.

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

or unlock everything with Pro →

About this simulation

The full Snell's Law tool models a laser beam 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 Snell's Law

Snell's Law for a camera lens Snell's Law for a fiber-optic cable Snell's Law for a microscope Snell's Law for a telescope Snell's Law for a prism Snell's Law for a rainbow Snell's Law for a hologram Snell's Law for a solar cell

Other ways to simulate a laser beam

Diffraction Grating for a laser beam Curved Mirrors for a laser beam Prism Dispersion for a laser beam Laser Cavity for a laser beam Fiber Optics for a laser beam Gaussian Beam for a laser beam

Frequently asked questions

How do I simulate a laser beam?: Open this page and use the live Snell's Law 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 laser beam from your own measurements.