Small capacitors like film and disk types may not have room on the case to write the value out completely . Often a code which consists of 2 or 3 numbers and an optional tolerance letter code will be used.
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.
