What is a 100 ohm resistor? What is a 100 ohm resistor? A 100 ohm resistor is one of the most common fixed resistors with a nominal resistance of 100Ω. It is used to limit current, prevent circuit overload, divide voltage or signal conditioning. It is widely used in electronic circuits, signal processing, power management, LED protection and other fields. https://www.jinftry.com/news/What-is-a-100-ohm-resistor-100-ohm-resistor-color-code