Capacitor Calculator — Series & Parallel Capacitance
Calculate equivalent capacitance for capacitors in series and parallel, plus RC time constants. Enter values, get total capacitance instantly — free, no signup.
Parallel
79.00 µF
C = ΣCᵢ
Series
5.9977 µF
1/C = Σ(1/Cᵢ)
τ = RC
790.00 ms
τ = R × C
How to use the capacitor calculator — series & parallel capacitance
Enter capacitances (µF) separated by commas. We compute the parallel sum, series equivalent, and the RC time constant for the parallel set.
Formula & explanation
Parallel: C_total = ΣC. Series: 1/C = Σ(1/C). τ = RC (seconds).
Examples
10, 22, 47 µF parallel = 79 µF, series ≈ 6.07 µF.
Frequently asked questions
- Why is parallel capacitance larger than any single capacitor?
- Parallel capacitors share the same voltage and their plate areas effectively add together, so total capacitance is the sum of all values.
- Why is series capacitance smaller than the smallest capacitor?
- In series the charge must flow through each capacitor in turn. The reciprocal formula (1/C_total = Σ 1/Cₙ) means the result is always less than the smallest value.
- What is the RC time constant (τ) used for?
- τ = RC tells you how quickly a capacitor charges or discharges through a resistor. After one τ the capacitor reaches ~63% of its final voltage; after 5τ it is considered fully charged.
- What unit should I enter — µF, nF, or pF?
- Enter all values in the same unit (µF by default). The results will be in that same unit. If your capacitors are in nF, divide by 1000 to convert to µF first.
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