Snell's Law
Calculate Snell's Law instantly with the exact formula and a worked example. Free online calculator — no signup, works on mobile.
Snell's Law
n₁
n₂
Incidence angle°
Refraction angle
19.4712°
More about: Snell's Law
What it calculates
The “Snell's Law” calculator computes Refraction angle in ° from 3 parameters: n₁, n₂, incidence angle (°).
A standard physics formula used in educational and engineering tasks.
Example calculation
With parameters n₁ = 1, n₂ = 1.5, Incidence angle = 30 ° the result is 19.47 ° (sin θ₁ / sin θ₂ = n₂/n₁).
How to use
- Enter the parameter values — every field above is adjustable with a slider.
- The result and related metrics are calculated automatically as you type.
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