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.
Several standards exist, which describe how the different components should be displayed. In the past, a lot of countries and even individual industries used their own standards, which can be confusing. Nowadays, the IEC 60617 standard is the international standard for these electronic symbols. However, 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:
Sometimes the symbol for a particular device is different when it is used in another field of application. For example, different symbols are used in electronics than, for example, in architecture and construction. On top of this, many local deviations from the international standards exist. The following table shows the most common resistor symbols for electronics design.
| Type | Abbreviation | IEC (International) | ANSI (US) |
| Fixed resistor | R |  |
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| Heater resistor |  |
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| Variable resistors | VR | ||
| Potentiometer | 
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| Trimming potentiometer |  |
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| Rheostat |  |
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| Preset resistor |
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| Dependent resistors | |||
| Photo resistor or Light dependent resistor | LDR |  |
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| Varistor or Voltage dependent resistor | VDR
RV MOV |
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| NTC thermistor | NTC
RT |
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| PTC thermistor | PTC
RT |
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| Magneto resistor or Magnetic dependent resistor | MDR |  |
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