Snell's Law Calculator

Enter three of any value below to calculate the fourth one

Snell's Law Calculator

How it works?

Snell's Law Calculator

Using the Snell's Law Calculator

Snell's Law describes how light bends when passing from one medium to another with different refractive indices.

Calculating Incident Angle

To find the incident angle (θ1), enter the refractive indices of the incident medium (n1) and the refracted medium (n2), and the refracted angle (θ2):

θ 1 = sin ⁡ n 2 n 1 ⁢ sin ⁡ θ 2

Calculating Refracted Angle

To find the refracted angle (θ2), enter the incident angle (θ1), and the refractive indices of the incident medium (n1) and the refracted medium (n2):

θ 2 = sin ⁡ n 1 n 2 ⁢ sin ⁡ θ 1

Calculating Incident Index

To find the incident index (n1), enter the refracted index (n2), incident angle (θ1), and refracted angle (θ2):

n 1 = n 2 ⁢ sin ⁡ θ 2 ⁢ sin ⁡ θ 1

Calculating Refracted Index

To find the refracted index (n2), enter the incident index (n1), incident angle (θ1), and refracted angle (θ2):

n 2 = n 1 ⁢ sin ⁡ θ 1 ⁢ sin ⁡ θ 2
snell's law

Snell’s Law: Why Light Bends and How We Can Predict It

Learn the basics of Snell’s law in this ephotonics article.