Capacitance Calculator Formula

Understand the math behind the capacitance calculator. Each variable explained with a worked example.

Formulas Used

Capacitance

capacitance = charge / voltage

Capacitance (μF)

capacitance_uf = (charge / voltage) * 1e6

Variables

Variable	Description	Default
`charge`	Charge(C)	0.001
`voltage`	Voltage(V)	5

How It Works

Capacitance

Capacitance measures the ability of a component to store electric charge per unit voltage.

Formula

C = Q / V

where Q is the stored charge in coulombs and V is the voltage across the capacitor. The unit is the farad (F).

Worked Example

A capacitor stores 0.001 C of charge at 5 V.

charge = 0.001voltage = 5

01C = Q / V
02C = 0.001 / 5
03C = 0.0002 F = 200 μF

Frequently Asked Questions

What is a farad?

One farad is the capacitance that stores one coulomb of charge per volt. In practice, most capacitors are measured in microfarads (μF) or picofarads (pF).

What determines the capacitance of a parallel plate capacitor?

C = epsilon * A / d, where epsilon is the permittivity of the dielectric, A is the plate area, and d is the plate separation.

What is a supercapacitor?

A supercapacitor can store thousands of farads by using extremely thin dielectric layers and large surface areas. They bridge the gap between capacitors and batteries.

Learn More

Guide

How to Calculate Capacitance

Understand how to calculate capacitance, read capacitor markings, combine capacitors in series and parallel, and use capacitance in timing and filter circuits.

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