Series and parallel resistor calculator
Compare both connections with a circuit diagram, tolerances and individual currents and powers.
Add your resistors, choose a connection and watch the circuit update. Both equivalent resistances are compared live; supply voltage is optional.
Your resistors
Leave blank for resistance only. DC voltage, ideal source.
One path: the current is shared and voltage divides between resistors.
Your circuit
Terminals A and B bound the network. Matching colours identify the same resistor. Scroll larger diagrams.
Equivalent resistance
Tolerance range: —
Extreme bounds with all resistors simultaneously at their lower or upper tolerance limit; not a statistical interval.
Total current
Total power
Enter a voltage to see currents and powers.
Same components, two connections
Individual resistor results
Each bar shows the share of total voltage across that resistor.
| Resistor | Value | Voltage | Current | Power | % |
|---|
Understand the calculation
Ohmic resistors under DC conditions. Voltages, currents and powers use nominal values. Wire resistance and source internal resistance are ignored. Thermal sizing and mixed networks are not modelled.