# Capacitor Coding

Small
value ceramic, mylar, and polyester type capacitors have their values
stamped on their bodies as a numerical code, 102, 473, etc. in

*very small print*.
These codes can easily be deciphered into a standard value in microfarads.

The first two digits of the
code indicate the two significant digits of the value.
The third digit is the number of zeros to the right. Writing the first
two digits, then the zeros will yield the value in picofarads.
If desired, that value can now be converted to microfarads by **moving the decimal point six places to the left**.

**Example 1:**
You have a capacitor with

**"103" ** stamped on it.

The first two digits are: 1 0

The third digit is: 3 so add three zeros to the 1 0 --> 1 0, 0 0 0 pf

Now to covert the 10,000pf to microfarads:

Move the decimal point to the left six places giving **0.01** microfarads.

**Example 2:**
You have another capacitor with

**"104" ** stamped on it.

The first two digits are: 1 0

The third digit is: 4 so add four zeros to the 1 0 --> 1 0 0, 0 0 0 pf

Now to covert the 100,000pf to microfarads:

Move the decimal point to the left six places giving **0.10** microfarads.

Values greater than 1 microfarad are also coded this way.

**Example 3:**
Number stamped on capacitor:

**223**
Decoded value: 22 + 000 = 22,000pF =

**0.022** microfarads

### Below is a table showing standard codes for different tolerances:

These letter codes are usually stamped on the capacitor next to or below
the value.

C = +/- 0.25pF |
M = +/- 20% |

D = +/- 0.5pF |
P = +100 - 0% |

J = +/- 5% |
Y = -20 +50% |

K = +/- 10% |
Z = -20 + 80% |

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