Spherical Capacitor Calculator
C = 4π ε₀ εᵣ ab/(b − a)
How to Use This Calculator
Enter inner and outer radii and the dielectric constant εᵣ, then calculate.
Formula
C = 4π ε0 εr ab / (b − a)
Valid for concentric spherical conductors with homogeneous dielectric.
Frequently Asked Questions
Can b be close to a?
Yes, but measurement tolerances become important when b − a is small.
What εᵣ should I use?
Air ≈ 1.0006; oils, ceramics, and plastics vary widely. Check datasheets.