Use this calculator when resistor branches share the same voltage and you want the lower combined equivalent resistance.
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Use this page when resistors are connected across the same two nodes and you need the equivalent resistance of the parallel network.
The main result is the total equivalent resistance, which will always be lower than the smallest resistor entered in a simple parallel network.
Two 100 ohm resistors in parallel give 50 ohms. Adding more parallel branches reduces the equivalent resistance further.
This page assumes ideal parallel resistor combinations. It does not include branch wiring resistance, tolerance spread, or reactive effects.
Parallel branches create more than one current path, so the combined opposition falls below the smallest single branch value.
Add resistor values in series to find the total equivalent resistance for a simple chain of components.
Use the Resistor Divider Calculator for practical circuit and electronics work involving resistor divider.
Solve for voltage, current, or resistance from any two values and validate all three when you already have a full set of measurements.
Solve power, voltage, or current from the other two values using the core electrical power relationships.