Capacitance Calculator

Calculate capacitance of parallel plate capacitors with different dielectric materials

Calculate Parallel Plate Capacitance

Select the dielectric material between the plates

Area where the plates overlap

Distance between the parallel plates

Absolute permittivity of the dielectric material (εᵣ = 0.0)

Capacitance Results

0.000
Picofarads (pF)
0.000000
Nanofarads (nF)
0.000000000
Microfarads (μF)
0.000e+0
Farads (F)
0.00
Relative Permittivity
εᵣ = ε/ε₀
0.000 pJ
Energy at 1V
E = ½CV² (at 1V)
NaN
Aspect Ratio
A/d (m)

Formula used: C = ε × A / d

Input values: A = 0.000e+0 m², d = 0.000e+0 m, ε = 8.854e-24 F/m

Dielectric: Vacuum (εᵣ = 0.00)

Capacitance Analysis

Example Calculations

Standard Air Capacitor

Plate Area: 100 cm² = 0.01 m²

Separation: 1 mm = 0.001 m

Dielectric: Air (ε = 8.859 × 10⁻¹² F/m)

Calculation: C = (8.859 × 10⁻¹² × 0.01) / 0.001 = 88.59 pF

Ceramic Capacitor

Plate Area: 25 mm² = 2.5 × 10⁻⁵ m²

Separation: 10 μm = 1 × 10⁻⁵ m

Dielectric: Ceramic (εᵣ = 10, ε = 8.854 × 10⁻¹¹ F/m)

Calculation: C = (8.854 × 10⁻¹¹ × 2.5 × 10⁻⁵) / (1 × 10⁻⁵) = 221 pF

Capacitance Units

F

Farad (F)

Base SI unit

1 F = 1 C/V

μF

Microfarad (μF)

10⁻⁶ F

Common for electrolytic caps

nF

Nanofarad (nF)

10⁻⁹ F

Film and ceramic capacitors

pF

Picofarad (pF)

10⁻¹² F

Small, precision capacitors

Dielectric Materials

📊

Relative Permittivity (εᵣ)

Higher εᵣ = higher capacitance

🔋

Breakdown Voltage

Maximum voltage before failure

🌡️

Temperature Stability

How capacitance varies with temperature

Dielectric Loss

Energy loss in AC applications

Understanding Capacitance and Capacitors

What is Capacitance?

Capacitance is the ability of a device to store electric charge. In a parallel plate capacitor, it depends only on the geometry (plate area and separation) and the dielectric material between the plates. It does not depend on the voltage or charge stored.

Parallel Plate Capacitor

  • Two plates: Parallel conducting surfaces
  • Dielectric: Insulating material between plates
  • Electric field: Uniform field between plates
  • Charge storage: Opposite charges on each plate

Capacitance Formula

C = ε × A / d

C: Capacitance (farads)

ε: Absolute permittivity (F/m)

A: Plate area (m²)

d: Separation distance (m)

Key Relationships

Permittivity: ε = εᵣ × ε₀

Energy stored: E = ½CV²

Charge relation: Q = CV

Current relation: I = C(dV/dt)

Applications: Energy storage, filtering, timing circuits, power factor correction, flash photography