Capacitance Calculator

Calculate capacitance from charge and voltage.

Check Capacitance Calculator

Capacitance
4.000e-4 F
Stored energy
0.005 J

Formula result

Check before you use it

What the numbers show

Capacitance in farads

The answer shows how much charge storage the component represents and how much energy it stores at the stated voltage.

Stored energy result

Use capacitance calculator for basic capacitor sizing, storage estimates, and introductory RC analysis.

Simple capacitor lookup

Farads are often large for practical circuits, so real components may be stated in microfarads or nanofarads.

Copy-ready formula handoff

Use this after solving the live calculator result, then paste the answer into a lab note, homework check, or engineering review.

Formula

C = Q / V, E = 0.5 * C * V^2

Inputs to check
  • Capacitance: Charge storage per volt of potential difference.
  • Charge: Stored electric charge.
  • Voltage: Potential difference across the capacitor.
Before copying
  • The relation assumes an ideal capacitor with a stable voltage-charge relationship.
  • Leakage, ESR, and dielectric effects are ignored.
  • Entering microfarads as farads; 47 microfarads is 0.000047 F, not 47 F.
  • Mixing charge in microcoulombs with voltage in volts without converting charge to coulombs first.
Capacitance Calculator result: [paste the solved value from the calculator above].
Formula used: C = Q / V,  E = 0.5 * C * V^2
Inputs checked: Capacitance, Charge, Voltage.
Assumptions: The relation assumes an ideal capacitor with a stable voltage-charge relationship. Leakage, ESR, and dielectric effects are ignored.
Worked example: Capacitor holds 0.002 C at 5 V. Enter Q = 0.002 C and V = 5 V. Apply C = Q / V. Use the solved capacitance to compute stored energy.
Next check: Entering microfarads as farads; 47 microfarads is 0.000047 F, not 47 F.

Equation context

Built for basic capacitor sizing, storage estimates, and introductory RC analysis. This page pairs the live calculator with the governing formula, variable glossary, and a worked example so the result is easier to trust and reuse.

Quick entry points

Use the calculator to verify arithmetic after you set up the formula yourself.

Change one input at a time to see which variable is driving the result.

Review the formula notes before using the answer in a lab or design check.

Variables to track

C
Capacitance

Charge storage per volt of potential difference. Unit: F.

Q
Charge

Stored electric charge. Unit: C.

V
Voltage

Potential difference across the capacitor. Unit: V.

Formula method and unit assumptions

Formula and example

C = Q / V, E = 0.5 * C * V^2

Worked example

Capacitor holds 0.002 C at 5 V

  1. 1Enter Q = 0.002 C and V = 5 V.
  2. 2Apply C = Q / V.
  3. 3Use the solved capacitance to compute stored energy.

Capacitance tells you the storage ability of the component, while stored energy tells you how meaningful that storage is at the actual voltage.

sourceload path

Assumptions

The relation assumes an ideal capacitor with a stable voltage-charge relationship.
Leakage, ESR, and dielectric effects are ignored.
Energy is derived after capacitance is solved, so unit consistency matters.

Common mistakes

Entering microfarads as farads; 47 microfarads is 0.000047 F, not 47 F.
Mixing charge in microcoulombs with voltage in volts without converting charge to coulombs first.
Using E = 0.5*C*V^2 for a changing discharge voltage without treating the initial and final voltage states.

Equation context and next checks

Formula and variable setup for Capacitance Calculator

Calculate capacitance from charge and voltage. The page is designed to help you move from the known values to the correct formula without rebuilding the derivation every time.

For capacitance calculator, the safest workflow is to confirm the unit system first, then map each symbol to the physical quantity in your problem statement before solving.

  • C: Capacitance (F) - Charge storage per volt of potential difference.
  • Q: Charge (C) - Stored electric charge.
  • V: Voltage (V) - Potential difference across the capacitor.

How to read the result

The answer shows how much charge storage the component represents and how much energy it stores at the stated voltage.

This tool is especially useful for basic capacitor sizing, storage estimates, and introductory RC analysis. The output becomes more trustworthy when you compare nearby cases instead of relying on one single run.

  • Capacitance in farads
  • Stored energy result
  • Simple capacitor lookup

Assumptions and limits

The calculator applies the standard textbook relation for this topic, which makes it a strong first-pass answer but not always a full real-world model.

Before you use the result in a lab, design review, or report, check whether the simplified assumptions still match the physical system you care about.

  • The relation assumes an ideal capacitor with a stable voltage-charge relationship.
  • Leakage, ESR, and dielectric effects are ignored.
  • Energy is derived after capacitance is solved, so unit consistency matters.

Quick glossary

Capacitance

Charge storage per volt of potential difference.

Charge

Stored electric charge.

Voltage

Potential difference across the capacitor.

Ideal model

A simplified physics model that omits secondary effects so the first-order relationship is easier to inspect.

Formula checks before using the result

Formula questions

Checks before using the result

When should I use the capacitance calculator?

Use capacitance calculator for basic capacitor sizing, storage estimates, and introductory RC analysis, especially when the governing formula is already known and the main need is a fast, transparent calculation.

What is the main thing the capacitance calculator tells me?

The answer shows how much charge storage the component represents and how much energy it stores at the stated voltage.

What can make the capacitance calculator answer inaccurate?

The answer is exact for the formula and assumptions on the page, but it can drift when the real system violates those assumptions. Common limits include The relation assumes an ideal capacitor with a stable voltage-charge relationship. Leakage, ESR, and dielectric effects are ignored. Energy is derived after capacitance is solved, so unit consistency matters.

Formula references and related examples

Formula Basis

Formula Notes And References

Farads are often large for practical circuits, so real components may be stated in microfarads or nanofarads.
Stored energy grows with the square of voltage.