# Capacitor Calculator

Our capacitor calculator will find **every missing parameter from a capacitor based on your input**.

With this tool, you can obtain a capacitor's **code**, **capacitance**, **tolerance**, **charge**, and **voltage** with ease. This calculator essentially works as a:

- Capacitor calculator;
- Capacitor code calculator;
- Capacitor charge calculator; and
- Voltage across capacitor calculator.

Just input any parameter, and our calculator will do the rest!

## What is a capacitor? Capacitor formula

We've talked about all the features within this tool, but they are of no use if we don't know what a capacitor is.

**A capacitor is a device that stores** **energy** **by means of an electric field**. Generally, capacitors use two conductors separated by a dielectric medium, and there are many different capacitor shapes (parallel plates, cylindrical, spherical, etc.).

The capacitor formula expresses the relation between the **charge** ($Q$) stored within the capacitor, its **capacitance** ($C$), and the **voltage** ($V$) used to hold that charge:

Using this formula, we can calculate the voltage across the capacitor if we know its capacitance value and the amount of charge it stores.

## Capacitor codes

We use codes to identify capacitors quickly using two values: their **capacitance** and **voltage rating**. Voltage rating tells us the maximum voltage the capacitor can withstand while functioning correctly.

For capacitors with capacitance greater than `100 µF`

, we can often find their value written directly on it (a `200 µF 25 V`

capacitor has a capacitance of `200 µF`

and works with voltages up to `25 V`

).

However, for lower capacitance values, we use a 3-digit capacitor code to identify it:

**First**and**second**digits tell us the**first two significant figures of the capacitance in pF**.- The
**third**digit is a**multiplier factor**. This number indicates which power of**10**we should use to multiply the first and second digits to get the actual value of the capacitance.

For example, to find the code for a `12 µF`

capacitor:

- First, we
**convert the capacitance to pF**and extract the**first two significant figures**:`12 µF = 12,000,000 pF`

, therefore,`12`

. - Now, we need to find which power of
`10`

we should multiply`12 pF`

by to get`12 µF`

.**Answer**:`6 th`

, since`12 * 10⁶ pF = 12 µF`

. - Finally, the code for this capacitor is:
`126`

.

The reverse is just as simple: if we call the third digit `n`

, we only need to **multiply the first two digits of the code by 10ⁿ** to get the capacitance in pF.

## Capacitor tolerance

We can usually find a letter next to the three-digit code. This letter indicates the range in which we can find the actual value of the capacitance.

Below, we gathered the most commonly used tolerance codes:

Letter | Capacitance |
---|---|

B | ±0.1 pF |

C | ±0.25 pF |

D | ±0.5 pF |

F | ±1% |

G | ±2% |

J | ±5% |

K | ±10% |

M | ±20% |

Z | +80%, -20% |