Science & Engineering

Capacitor Calculator

Capacitor Energy Calculator uses capacitance in microfarads and voltage in volts to find the stored energy (half C V squared) in joules and the charge (C times V) in coulombs.

What this calculator does

The Capacitor Calculator estimates your result instantly from the values you enter, using standard science & engineering formulas. Capacitor Energy Calculator uses capacitance in microfarads and voltage in volts to find the stored energy (half C V squared) in joules and the charge (C times V) in coulombs. Calculations run in your browser, so nothing you type is sent to a server, and the output is an estimate rather than a certified or official figure.

Capacitor Energy Calculator

Result

—
Energy Stored (J)
—
Charge (C)

About Capacitor Calculator

A charged capacitor stores both electric charge and energy.

Enter the capacitance in microfarads and the voltage; the tool converts to farads, then computes energy as ½CV² and charge as CV.

Formula & Mathematical Calculation

Energy Stored (J) = f(Capacitance (µF), Voltage (V))

Calculated according to standard science formulas implemented in the calculator core.

Calculation Example

For C = 100 µF (1 × 10-4 F) and V = 12 V:

E = ½ × 1 × 10-4 × 12² = 7.2000e-3 J and Q = 1 × 10-4 × 12 = 1.2000e-3 C.

Key Benefits

  • Converts microfarads to farads before calculating
  • Returns both stored energy and charge
  • Uses E = 1/2 C V^2 and Q = CV exactly
  • Reports results in scientific notation to four decimals

How to Use this Calculator

  1. Enter capacitance
    Type the capacitance in microfarads in the Capacitance field.
  2. Enter voltage
    Type the voltage in volts in the Voltage field.
  3. Calculate
    Select Calculate to compute energy and charge.
  4. Read results
    Read Energy Stored (J) and Charge (C) in the result boxes.

Assumptions & Limitations

What the calculation assumes

  • Every value you enter is treated as an exact, known amount.
  • Any rate or interval you enter is assumed to hold for the whole period unless the form asks for it separately.
  • Results use standard published formulas and account only for the values entered above.
  • Rounding is applied for display; the underlying calculation uses your full precision.
  • Results are returned in the same units you enter, unless the tool states the output unit.

What it does not cover

  • Capacitor Calculator produces a calculated result for reference and learning, not a certified or official measurement.
  • Real-world outcomes differ when tolerances, rounding rules or local standards apply.
  • Definitions and standards vary by region and change over time; verify the convention that applies to your case.
  • Figures are only as accurate as the inputs you supply — check them before acting on the result.
  • For work where the result carries real consequences, confirm it against an authoritative source.

Frequently Asked Questions

Microfarads; the tool converts to farads by multiplying by 1e-6 before calculating.

Stored energy is one half times capacitance times voltage squared, and charge is capacitance times voltage.

Capacitor energies and charges are small, so results are shown in exponential form to four decimals.

No, energy uses voltage squared, so the sign of the voltage does not change the energy.

Free to use, no account needed. Calculations run in your browser, so nothing you type is sent to a server. Results are estimates — how we build and check our calculators.