Please enter all required numeric values.
Formulas & Mathematical Logic
Main formula: C = Q / V. Capacitance equals stored charge divided by voltage.
Charge conversion: if mC is selected, Q = entered charge / 1000.
Charge conversion: if µC is selected, Q = entered charge / 1000000.
Parallel plate meaning: C = εA / d. Larger plate area increases capacitance, while larger plate spacing reduces capacitance.
Practical meaning: a capacitor with higher capacitance stores more charge at the same voltage.
Step-by-Step Example
Example values: charge = 500 mC, voltage = 10 V.
Convert charge: 500 mC = 500 / 1000 = 0.5 C.
Apply formula: C = Q / V = 0.5 / 10.
Capacitance = 0.05 F.
Practical meaning: this capacitor stores 0.5 coulomb of charge when charged to 10 volts.
About This Calculator
Find capacitance from charge and voltage without rearranging the formula manually.
This CalcBoy calculator uses C = Q / V to calculate capacitance in farads from stored charge and applied voltage.
The Capacitance Calculator is useful for electronics students, circuit designers and anyone learning how capacitors store electrical energy. Capacitance describes how much electric charge a capacitor can store for each volt applied across its terminals. A larger capacitance means the capacitor can hold more charge at the same voltage.
Best UseCapacitor sizing, charge storage checks, electronics learning and circuit formula practice.
Key InputsCharge value, charge unit and capacitor voltage.
Design BenefitQuickly convert charge and voltage into capacitance.
Practical ReminderReal capacitors also have voltage rating, tolerance, leakage, ESR and dielectric limits.
In a physical capacitor, two conductive plates are separated by an insulating dielectric material. When voltage is applied, positive and negative charge collect on opposite plates. The dielectric allows electric field energy to be stored without direct conduction between the plates. Plate area, dielectric permittivity and distance between plates all affect capacitance.
Quick tip: always choose a capacitor voltage rating higher than the maximum circuit voltage, not equal to it.
This calculator focuses on the basic charge-voltage relationship. For real circuit design, also check capacitance tolerance, ripple current, ESR, temperature rating, dielectric type and leakage current. Ceramic, electrolytic, film and supercapacitors behave differently, so the calculated value is only one part of component selection.
Frequently Asked Questions
What is capacitance?
Capacitance is the ability of a capacitor to store electric charge per volt.
What is the formula for capacitance?
The basic formula is C = Q / V, where C is capacitance, Q is charge and V is voltage.
What unit is capacitance measured in?
Capacitance is measured in farads, written as F.
Does higher voltage mean higher capacitance?
No. Capacitance is a component property. Higher voltage stores more charge only if the capacitance stays the same.
Why does plate distance matter?
For a parallel plate capacitor, larger distance reduces capacitance because the electric field coupling becomes weaker.
Can I use this for real capacitors?
Yes, for basic calculations. Real capacitor selection should also consider voltage rating, tolerance, ESR, leakage and temperature.