Series Capacitance Calculator Formula

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

Formulas Used

Total Capacitance

total_capacitance = 1 / (1/c1 + 1/c2)

Variables

VariableDescriptionDefault
c1Capacitor 1(μF)100
c2Capacitor 2(μF)220

How It Works

Series Capacitance

Capacitors in series have reciprocal addition, opposite to resistors.

Formula

1/C_total = 1/C1 + 1/C2 + ...

The total capacitance is always less than the smallest individual capacitor. This is the opposite behavior from resistors in series.

Worked Example

Two capacitors in series: 100 μF and 220 μF.

c1 = 100c2 = 220
  1. 011/C = 1/100 + 1/220 = 0.01 + 0.004545 = 0.014545
  2. 02C = 1 / 0.014545 = 68.75 μF

Frequently Asked Questions

Why does series capacitance decrease?

In series, the same charge appears on each capacitor but the voltages add. Higher total voltage for the same charge means lower effective capacitance.

When would you put capacitors in series?

To achieve a lower capacitance than available or to increase the voltage rating (each capacitor only sees part of the total voltage).

Is the formula the same as parallel resistance?

Yes, the reciprocal addition formula is identical. Capacitors in series combine like resistors in parallel.

Ready to run the numbers?

Open Series Capacitance Calculator