Combine capacitors in series or parallel into one equivalent value, auto-scaled to pF, nF or µF.
About this tool
Series & Parallel Capacitor Calculator is a free, in-browser tool that reduces a group of capacitors to a single equivalent capacitance. It runs entirely in your browser and uploads nothing.
Capacitors combine the opposite way to resistors. In parallel the capacitances add, Ct = C1 + C2 + …, so the total grows. In series the reciprocals add, 1/Ct = 1/C1 + 1/C2 + …, so the equivalent is smaller than the smallest capacitor. Enter your values separated by commas, choose a base unit (pF, nF or µF), and each entry may also carry a p, n or µ suffix.
Use it to size a bank of capacitors, to see the effect of stacking two in series to raise the voltage rating, or to check a filter network. The total is auto-scaled to the most readable of pF, nF or µF and recalculates live as you edit the list.
Frequently asked questions
How do series and parallel capacitors differ?
This is the reverse of resistors. Parallel capacitors add: Ct = C1 + C2 + … . Series capacitors add as reciprocals: 1/Ct = 1/C1 + 1/C2 + …, giving a total smaller than any single capacitor in the chain.
Why would I put capacitors in series?
Series lowers the total capacitance but shares the voltage across each part, so two identical capacitors in series roughly double the voltage rating at half the capacitance — a common trick for high-voltage designs.
What units can I enter?
Pick a base unit of pF, nF or µF for bare numbers, and individual entries may end in p, n or µ to override it. So 100, 4.7µ, 1n can appear together in one list.
Does this run offline?
Yes. All the arithmetic happens in your browser; the capacitor list is never uploaded and the tool works with no network connection.