Calculadora de Capacitância
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
C = Q/V
About this calculator
The capacitance calculator determines the capacitance of a capacitor from the stored electric charge and the applied voltage. Capacitance, measured in farads (F), is the ratio of charge Q (in coulombs) to voltage V (in volts). This tool is useful for students, engineers, and technicians working with electrical and electronic circuits.
Operation is simple: enter the charge and voltage values in the corresponding fields and click calculate. The formula C = Q/V is applied automatically, displaying the result in farads, microfarads, or other common units. Make sure to use consistent units (coulombs and volts) for an accurate result.
Use this calculator when designing circuits, sizing capacitors for power supplies, or in laboratory experiments. For example, knowing the charge a capacitor needs to store and the operating voltage, you can select the appropriate component. It is also useful for checking the capacitance of unknown capacitors by measuring charge and voltage with proper equipment.
Cautions: capacitance depends on the capacitor geometry and dielectric material, but this calculator does not consider these factors. Also, in real circuits, the maximum voltage (Vmax) should not be exceeded to avoid damage. Always check polarity in electrolytic capacitors and use calibrated instruments for precise measurements.
Frequently asked questions
What is capacitance?
Capacitance is the ability of a capacitor to store electric charge, defined by the relation C = Q/V, where Q is charge and V is voltage.
What units can I use for charge and voltage?
Use coulombs (C) for charge and volts (V) for voltage. The calculator automatically converts to farads, microfarads, etc.
Can I use this calculator for electrolytic capacitors?
Yes, but remember that electrolytic capacitors have polarity and a maximum voltage. The calculator does not check these limits.
How do I measure the charge stored in a capacitor?
Charge can be measured indirectly: Q = I * t, where I is constant current and t is charging time. Use a multimeter or current integrator.
Does capacitance depend on temperature?
Yes, capacitance can vary with temperature due to changes in the dielectric. Consult the capacitor datasheet for temperature coefficients.