A two number code is the value of the cap in picofarads (ie. 47 = 47 pF)
A three letter codes consist of two significant digits and a multiplier much like a resistor color code. The first two numbers are the digits and the third is the multiplier. Three digit codes are often accompanied by a tolerance letter code.
The cap pictured above has the code 473J which translates to:
47 * 1,000 = 47,000 pf or 0.047 uF
The J indicates a tolerance of +/- 5%
The chart below will help you decipher most capacitor codes.
| Multiplier | Tolerance | ||||
|---|---|---|---|---|---|
| Digit | Multiplier | Letter | 10 pF or less | Over 10 pF | |
| 0 | 1 | B | +/- 0.1 pF | ||
| 1 | 10 | C | +/- 0.25 pF | ||
| 2 | 100 | D | +/- 0.5 | ||
| 3 | 1,000 | F | +/- 1 pF | +/- 1% | |
| 4 | 10,000 | G | +/- 2 pF | +/- 2% | |
| 5 | 100,000 | H | +/- 3% | ||
| 6 | J | +/- 5% | |||
| 7 | K | +/- 10% | |||
| 8 | 0.01 | M | +/- 20% | ||
| 9 | 0.1 | P | +100%, -0% | ||
| Z | +80%, -20% | ||||