This resistor color code calculator will help you determine the value of axial resistors marked with color bands. It can be used for 3, 4, 5 and 6 band resistors. You can select the colors of the corresponding bands by clicking on them in the table. The resistor will visually show your band color choices and display the value of the resistor above. If the resistance value is part of a standard E-series value, this will be shown in brackets after the resistance value. How to use the color code calculator Select the amount of bands of the resistor on the top-left Choose the colors of the bands by clicking on the corresponding box in the chart The corresponding ohmic value and tolerance of the resistor is shown Bands: 3 4 5 6 10k&#8486 ±5% 1st digit 2nd digit 3rd digit multiply tolerance TCR(ppm/K) Bad Black 0 0 0 1 1% (F) 100 Beer Brown 1 1 1 10 2% (G) 50 Rots Red 2 2 2 100 15 Our Orange 3 3 3 1K 25 Young Yellow 4 4 4 10K Guts Green 5 5 5 100K 0.5% (D) But Blue 6 6 6 1M 0.25% (C) 10 Vodka Violet 7 7 7 10M 0.1% (B) 5 Goes Gray 8 8 8 100M 0.05% (A) Well White 9 9 9 1G Get Gold 0.1 5% (J) Some Silver 0.01 10% (K) Now None 20% (M) Special cases 6 band resistors In the case of 6 band resistors, this calculator assumes the 6th band is used to indicate the thermal coefficient. In some rare cases the 6th band can also indicate the reliability of the resistor. For more information visit the main page on the resistor color code. Disclaimer While we did our best to check all possibilities and remove [… read more]

All types of resistors have their own resistor symbols which are used when a circuit diagram is drawn. This page will explain the different standards which are used for resistor symbols and display the most common symbols. Standards for resistor symbols Several standards exist, which describe how the different components should be displayed. In the past a lot of countries or even industries used their own standards, which can be confusing. Nowadays the IEC 60617 standard is international standard for these electronic symbols. However the local standards are still used from time to time. In general, the ANSI standard is still common in the United States. Some examples of standards which describe resistor symbols: IEC 60617 (International) ANSI Y32 / IEEE 315 (US) – old DIN 40900 (Germany) – old AS 1102 (Australia) – old Sometimes the symbol for a particular device is different when it is used in another field of application. Other symbols are used in electronics then for example in architecture and buildings. On top of this, many local deviations from the international standards exist. The following table shows the most common resistor symbols for electronics design. Schematic symbols  Type Abbreviation IEC (International) ANSI (US) Fixed resistor R Heating resistor Variable resistors VR Potentiometer Trimming potentiometer Rheostat Preset resistor Dependent resistors Photo resistor orLight dependent resistor LDR     Varistor or Voltage dependent resistor  VDRRVMOV  NTC thermistor NTCRT PTC thermistor PTCRT Magneto resistor orMagnetic dependent resistor   MDR

Standard resistor values 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. Preferred values or E-series As basis the E12 has been developed. E12 means that every decade (0.1-1, 1-10, 10-100 etc) is divided in 12 steps. The size of every step is equal to:   One could also say every value is 21% or 1.21 times higher than the last, rounded to whole numbers. Because of this, all resistors with a tolerance of 10% overlap. The series looks as follows: 1– 1.2 – 1.5 – 1.8 – 2.2 – 2.7 – 3.3 – 3.9 – 4.7 – 5.6 – 6.8 – 8.2 – 10 etc. All these values [… read more]