Index of Refraction Calculator

Find a medium's refractive index from light speed.

Refractive index 1.332

Formula: n = c ÷ v

Step-by-step with your numbers:

1. Values used:

2. Speed of light in medium = 225,000,000

4. Refractive index = 1.332

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The refractive index shows how much a material slows light.

The math behind it

n = speed of light in vacuum (299,792,458 m/s) ÷ speed in the medium.

2.25 × 10⁸ m/s → n ≈ 1.33 (water).

Higher n?

Light travels slower and bends more.