Refractive Index Calculator
🔍 Light & optics. Use the Refractive index formula to find refractive index n, speed of light in it: pick the value you want, type the others, and the answer updates as you go.
Refractive index n1.499
Pick the ○ next to the value you want to find, fill in the others, and it solves as you type.
What each letter means
| Quantity | Unit |
|---|---|
| Refractive index n | no unit |
| Speed of light in it | m/s |
Worked example
Find the refractive index n when Speed of light in it = 2 × 10⁸ m/s.
Using n = c/v: Refractive index n = 1.499.
Frequently asked questions
What is the formula for Refractive index?
n = c/v.
What do the letters stand for, and what units are used?
Refractive index n, Speed of light in it in m/s.
How do you calculate refractive index n?
Put the values into n = c/v. For example, with Speed of light in it = 2 × 10⁸ m/s, refractive index n = 1.499.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (refractive index n, speed of light in it) and fill in the others: it rearranges the formula for you.
