Capacitors in Series Calculator
Calculate the total capacitance of capacitors connected in series
Enter values in microfarads (µF), separated by commas
How to Use This Calculator
Enter Capacitor Values
Enter the capacitance values in microfarads (µF), separated by commas. For example: 100, 220, 470
Calculate Total
Click the calculate button to get the total capacitance when these capacitors are connected in series.
View Results
The result shows the total capacitance in microfarads (µF) or nanofarads (nF), depending on the value. The total is always less than the smallest capacitor.
Formula
1/Ctotal = 1/C1 + 1/C2 + 1/C3 + ...
Ctotal = 1 / (1/C1 + 1/C2 + 1/C3 + ...)
Where:
- Ctotal = Total capacitance (F)
- C1, C2, C3 = Individual capacitances (F)
Special Case - Two Capacitors:
Ctotal = (C1 × C2) / (C1 + C2)
Key Points:
- Series connection reduces total capacitance
- Total capacitance is always less than the smallest capacitor
- For two equal capacitors, total = half of one
- Voltage across series capacitors divides proportionally to inverse capacitance
Example 1:
Capacitors: 100 µF, 220 µF, 470 µF
1/Ctotal = 1/100 + 1/220 + 1/470
1/Ctotal = 0.01 + 0.004545 + 0.002128 = 0.016673
Ctotal = 1 / 0.016673 = 59.98 µF
Example 2:
Capacitors: 10 µF, 10 µF (two equal capacitors)
Ctotal = (10 × 10) / (10 + 10) = 100 / 20 = 5 µF
About Capacitors in Series Calculator
The Capacitors in Series Calculator is a free online tool that helps you calculate the total capacitance when multiple capacitors are connected in series. When capacitors are connected in series, the total capacitance is always less than the smallest individual capacitor. This is the opposite of resistors in series, and understanding this relationship is crucial for circuit design.
When to Use This Calculator
- Circuit Design: Calculate total capacitance in series capacitor networks
- Voltage Rating: When you need higher voltage rating by connecting lower-voltage capacitors in series
- Precise Values: Achieve specific capacitance values not available as standard components
- Filter Design: Design filters and timing circuits with series capacitors
- Educational Purposes: Learn about series capacitor connections and capacitance calculations
Why Use Our Calculator?
- ✅ Accurate Calculations: Uses the correct series capacitance formula
- ✅ Multiple Capacitors: Handles any number of series-connected capacitors
- ✅ Easy to Use: Simple comma-separated input format
- ✅ Multiple Units: Displays results in µF or nF as appropriate
- ✅ Free Tool: No registration or payment required
- ✅ Educational: Includes formulas and examples for learning
Common Applications
Voltage Rating Increase: When you need a capacitor for high voltage but only have lower-voltage capacitors available, connecting them in series increases the voltage rating. For example, two 25V, 100µF capacitors in series give you 50V rating with 50µF total capacitance.
Precise Capacitance Values: Sometimes you need a specific capacitance value that isn't available as a standard component. By connecting capacitors in series, you can achieve values like 33.3µF from 100µF and 50µF capacitors.
High-Voltage Applications: In high-voltage circuits, series connection of capacitors is common to distribute voltage stress across multiple capacitors, preventing individual capacitor failure.
Coupling Circuits: In some AC coupling applications, series capacitors are used to achieve specific reactance values at certain frequencies.
Tips for Accurate Results
- Enter all capacitance values in microfarads (µF)
- Separate values with commas (e.g., 100, 220, 470)
- Total capacitance is always less than the smallest individual capacitor
- For voltage division, smaller capacitors have higher voltage across them
- Consider using voltage balancing resistors for high-voltage series connections
- Actual capacitance may vary slightly due to component tolerance
Frequently Asked Questions
Why does series connection reduce capacitance?
When capacitors are in series, the effective plate separation increases, reducing capacitance. The total capacitance is the reciprocal of the sum of reciprocals, which always results in a value smaller than the smallest capacitor.
How does voltage divide across series capacitors?
Voltage divides inversely proportional to capacitance. The smaller capacitor gets more voltage. For example, if you have 10µF and 20µF in series, the 10µF capacitor gets 2/3 of the voltage, and the 20µF gets 1/3.
Can I mix different voltage ratings in series?
Yes, but be careful. The total voltage rating is the sum of individual ratings, but voltage will divide inversely with capacitance. Smaller capacitors may exceed their rating. Use voltage balancing resistors for safety.
What's the difference between series and parallel capacitors?
Series connection reduces total capacitance (like resistors in parallel), while parallel connection increases total capacitance (like resistors in series). Series: 1/Ctotal = 1/C1 + 1/C2. Parallel: Ctotal = C1 + C2.
Do I need balancing resistors for series capacitors?
For high-voltage applications or when capacitors have different leakage currents, balancing resistors are recommended. They ensure equal voltage division and prevent one capacitor from being overstressed.