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Capacitors in Series & Parallel
Calculate the equivalent capacitance of two or three capacitors connected in series or parallel, with quick unit conversion between pF, nF and µF.
Voltage rating still matters. Equivalent capacitance does not by itself tell you the safe working voltage of a capacitor network. Series-connected electrolytics may also need balancing resistors to share voltage reliably.
Formula
Series and parallel capacitor rules
Parallel capacitors
Capacitances add directly: C total = C1 + C2 + C3.
Series capacitors
The reciprocal values add: 1/C total = 1/C1 + 1/C2 + 1/C3. Two equal capacitors in series give half the capacitance of one capacitor.