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Snell's Law Calculator — Free Online Calculator
Snell's Law solves n₁ sin(θ₁) = n₂ sin(θ₂) — n₁, n₂ = refractive indices of the two media, θ₁, θ₂ = angles from the normal. Enter your known values and the calculator solves for the rest instantly. Everything is computed locally in your browser — your data never leaves your device. Completely free, with no account required.
How to use Snell's Law
- Enter your known values in the fields.
- The result updates instantly as you type.
- Copy or note down the result.
Frequently asked questions
- What formula does Snell's Law use?
- n₁ sin(θ₁) = n₂ sin(θ₂) — n₁, n₂ = refractive indices of the two media, θ₁, θ₂ = angles from the normal.
- Can I use it on my phone?
- Yes. The layout adapts to small screens and behaves the same on mobile as on desktop.
- Is my input saved anywhere?
- No. Values stay in your browser and are gone as soon as you close the tab.
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