Capacitor Charge Calculator
Solve Q = C × V and E = ½CV² — enter any two of charge, capacitance, or voltage to compute the third plus stored energy.
Capacitor Parameters
Select what you want to solve for, enter the two known values.
Result
Enter values and click Calculate.
Charge (Q)
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Energy Stored (E)
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E = ½ × C × V²
All Values
- Capacitance
- —
- Voltage
- —
- Charge
- —
Formulas
- Q = C × V Charge = Capacitance × Voltage
- E = ½ C V² Energy stored in the electric field
- C = Q / V Capacitance from charge and voltage
- V = Q / C Voltage from charge and capacitance
Summary
Solve Q = C × V and E = ½CV² — enter any two of charge, capacitance, or voltage to compute the third plus stored energy.
How it works
- Select which quantity you want to solve for: charge (Q), capacitance (C), or voltage (V).
- Enter the two known values with their units.
- Click Calculate to get the missing value and the stored energy.
- Results are shown in standard SI units with scientific notation for very small or large values.
- Use Reset to clear all fields and start a new calculation.
Use cases
- Calculate charge stored in a capacitor for a given capacitance and voltage.
- Find the capacitance needed to store a target charge at a specific voltage.
- Determine the voltage across a capacitor from its charge and capacitance.
- Compute energy stored in capacitor banks for power electronics design.
- Verify capacitor sizing in RC filter and timing circuits.
- Check energy storage in defibrillator or flash capacitor circuits.
- Homework and exam problems involving basic electrostatics.
Frequently Asked Questions
Last updated: 2026-06-10 ·
Reviewed by Nham Vu