Diffraction Grating Calculator
🔍 Light & optics. Use the Diffraction grating formula to find slit spacing, angle θ, order n, wavelength λ: pick the value you want, type the others, and the answer updates as you go.
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 |
|---|---|
| Slit spacing | m |
| Angle θ | ° |
| Order n | no unit |
| Wavelength λ | m |
Worked example
Find the slit spacing when Angle θ = 17.46 °, Order n = 1, Wavelength λ = 6 × 10⁻⁷ m.
Using d sinθ = nλ: Slit spacing = 2 × 10⁻⁶ m.
Frequently asked questions
What is the formula for Diffraction grating?
d sinθ = nλ.
What do the letters stand for, and what units are used?
Slit spacing in m, Angle θ in °, Order n, Wavelength λ in m.
How do you calculate slit spacing?
Put the values into d sinθ = nλ. For example, with Angle θ = 17.46 °, Order n = 1, Wavelength λ = 6 × 10⁻⁷ m, slit spacing = 2 × 10⁻⁶ m.
Can I solve for a different value?
Yes. In the calculator above, pick the circle next to any value (slit spacing, angle θ, order n, wavelength λ) and fill in the others: it rearranges the formula for you.
