Resistors and Capacitors are types of passive electronic components. The basic unit of resistance is the ohm (Ω) and capacitance is Farad.

Standard base resistor values are given in the following tables for the most commonly used tolerances (1%, 2%, 5%, 10%), along with typically available resistance ranges.

In 1952 the IEC (International Electrotechnical Commission) decided to define the resistance and tolerance values into a norm, to ease the mass manufacturing of resistors. These are referred to as preferred values or E-series, and they are published in standard IEC 60063:1963. These standard values are also valid for other components like capacitors, inductors and Zener diodes. The preferred values for resistors were established in 1952, but the concept of the geometric series was already introduced by army engineer Renard in the 1870s.

The standardization of resistor values serves several important purposes. When manufacturers produce resistors with different resistance values, these end up approximately equally spaced on a logarithmic scale. This helps the supplier to limit the number of different values that have to be produced or kept in stock. By using standard values, resistors of different manufacturers are compatible for the same design, which is favorable for the electrical engineer.

Aside from the preferred values, many other standards related to resistors exist. An example is standard sizes for resistors, or the marking of resistors with color codes or numerical codes. Power ratings of resistors are not defined in a norm, therefore often is deviated from the above described series.

Standard Resistor Values

Standard Capacitor Values

Capacitor IEC and EIA Codes

Ceramic capacitor have EIA or IEC code on it. from below table value of capacitor can be known.

On SMD ceramic capacitor there is no marking or numbering you have to measure it using capacitance meter.