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Capacitor Charge Calculator

Result

0.012000C

Result: 0.012000 C

Charge is capacitance times voltage: a 1000 µF capacitor at 12 V holds 0.012 C. Double the voltage and it holds twice the charge — but four times the energy, because energy goes with the square.

The numbers at a glance

Held fixed: Capacitance 0.001000000 F.

Voltage (V)Result (C)
0.000.000000
5.000.005000
10.000.010000
12.00Your value0.012000
15.000.015000
20.000.020000

Worked examples

How it's calculated

Q = C × V

  1. StepEnter the capacitance in farads — 1000 µF is 0.001.
  2. StepEnter the voltage across the capacitor's terminals.
  3. ResultMultiply; the result is the stored charge in coulombs.

Reference table

Capacitance, voltageWhat that isCharge
0.000001, 51 µF on a 5 V rail0.000005
0.0001, 10100 µF at 10 V0.001
0.01, 1A 10 mF supercap at 1 V0.01
0.001, 121000 µF on a 12 V supply0.012

Questions

How much charge does a capacitor hold?

Its capacitance in farads times the voltage across it, giving coulombs. A 1000 µF capacitor at 12 V holds 0.012 C.

How much energy is that?

Energy is half the capacitance times the voltage squared, so the same part holds 0.072 J. Note that doubling the voltage doubles the charge but quadruples the energy.

What happens at zero volts?

The charge is exactly zero. A capacitor with no voltage across it stores nothing, however large its capacitance.

Can I exceed the printed voltage rating?

No. The rating is a limit on the dielectric, not a suggestion, and an electrolytic that is pushed past it can vent or fail short. Stay well below it, especially where ripple or transients are present.

Sources and last check

  1. en.wikipedia.org

Information, not professional advice.