Capacitor Calculator

Calculate capacitance, charge, voltage, and stored energy. Free online capacitor calculator with formulas, unit conversion, and step-by-step explanations.

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Capacitor Calculator

Calculate capacitance, charge, voltage, and stored energy with instant results and step-by-step explanations.

Calculation Mode

Input Values

Capacitance (C)

Voltage (V)

Note: This calculator uses standard capacitor formulas. Results are based on ideal conditions. Actual values may vary due to component tolerances, temperature effects, and other real-world factors.

What is a Capacitor Calculator?

A Capacitor Calculator is an educational and engineering tool that helps you calculate electrical properties of capacitors including capacitance, charge, voltage, and stored energy. Using fundamental capacitor formulas, this calculator provides instant results with step-by-step explanations.

This tool is essential for electrical engineering students, physics learners, circuit designers, electronics hobbyists, and professionals who need quick and accurate capacitor calculations.

Capacitor Formulas

The calculator uses these fundamental capacitor equations:

Charge Formula

Q = C × V

Where Q is charge (Coulombs), C is capacitance (Farads), and V is voltage (Volts)

Capacitance Formula

C = Q ÷ V

Calculate capacitance when you know charge and voltage

Voltage Formula

V = Q ÷ C

Calculate voltage when you know charge and capacitance

Energy Formula

E = ½ × C × V²

Calculate energy stored in a capacitor (Joules)

Example Calculations

Example 1: Calculate Charge

Given: Capacitance = 10µF, Voltage = 5V

Formula: Q = C × V

Calculation: Q = 0.00001 F × 5 V = 0.00005 C

Result: 50 µC (microcoulombs)

Example 2: Calculate Capacitance

Given: Charge = 0.002C, Voltage = 10V

Formula: C = Q ÷ V

Calculation: C = 0.002 C ÷ 10 V = 0.0002 F

Result: 200 µF (microfarads)

Example 3: Calculate Energy

Given: Capacitance = 100µF, Voltage = 12V

Formula: E = ½ × C × V²

Calculation: E = 0.5 × 0.0001 F × (12 V)² = 0.0072 J

Result: 7.2 mJ (millijoules)

Understanding Capacitor Units

Property	Symbol	SI Unit	Common Units
Capacitance	C	Farad (F)	µF, nF, pF
Charge	Q	Coulomb (C)	µC, nC, mC
Voltage	V	Volt (V)	V, mV, kV
Energy	E	Joule (J)	J, mJ, µJ

Unit Prefixes:

p (pico) = 10⁻¹² = 0.000000000001
n (nano) = 10⁻⁹ = 0.000000001
µ (micro) = 10⁻⁶ = 0.000001
m (milli) = 10⁻³ = 0.001
k (kilo) = 10³ = 1000

How to Use This Calculator

Select Calculation Mode: Choose what you want to calculate (Charge, Capacitance, Voltage, or Energy)
Enter Known Values: Input the values you know with appropriate units
View Results: The calculator instantly shows the result with step-by-step calculations
Check Conversions: See the result in multiple units for convenience
Copy or Export: Save your calculation for future reference

Common Capacitor Values

Type	Typical Range	Common Uses
Ceramic	1pF - 1µF	High-frequency circuits, decoupling
Electrolytic	1µF - 10,000µF	Power supplies, audio circuits
Film	100pF - 10µF	Precision circuits, audio
Tantalum	0.1µF - 1000µF	Compact designs, portable devices

Benefits of Using This Calculator

Instant Results: Get calculations in real-time as you type
Multiple Modes: Calculate charge, capacitance, voltage, or energy
Unit Conversion: Automatic conversion between different units
Step-by-Step: See detailed calculation steps for learning
Educational: Perfect for students learning electronics
Professional: Quick calculations for circuit design
No Installation: Works entirely in your browser
History Tracking: Save and review past calculations

Frequently Asked Questions

What is a capacitor?

A capacitor is an electronic component that stores electrical energy in an electric field. It consists of two conductive plates separated by an insulating material (dielectric).

What is capacitance?

Capacitance is the ability of a capacitor to store electric charge. It is measured in Farads (F), though practical capacitors are usually measured in microfarads (µF), nanofarads (nF), or picofarads (pF).

How do I read capacitor values?

Capacitor values are often marked on the component. For example, "104" means 10 × 10⁴ pF = 100,000 pF = 100 nF = 0.1 µF. The first two digits are the value, and the third is the multiplier (number of zeros).

What is the difference between charge and capacitance?

Capacitance (C) is the capacity to store charge, measured in Farads. Charge (Q) is the actual amount of electrical charge stored, measured in Coulombs. They are related by Q = C × V.

How much energy can a capacitor store?

The energy stored in a capacitor is calculated using E = ½CV². For example, a 100µF capacitor charged to 12V stores 0.0072 Joules (7.2 millijoules) of energy.

Can I use this calculator for supercapacitors?

Yes! The formulas work for all types of capacitors, including supercapacitors (ultracapacitors). Just use the appropriate capacitance value, which can be several Farads for supercapacitors.