Parallel Resistor Calculator
Total resistance in parallel and series.
Enter your values
ⓘ Live results
Results
- Parallel resistance
- 59.9768 Ω
- Series resistance
- 790 Ω
- Current (parallel)
- 0.20008 A
- Power dissipated
- 2.4009 W
- Resistors entered
- 3
Quick answer
Parallel resistance is the reciprocal of the sum of reciprocals, and is always lower than the smallest resistor.
1/Rt = 1/R₁ + 1/R₂ + …
How to use the Parallel Resistor Calculator
- 1Enter each resistance in ohms, comma separated.
- 2Add the supply voltage for current and power.
- 3Compare parallel and series totals.
Worked example
Using the values the calculator loads with:
Inputs
- Resistances (ohms)100, 220, 470
- Applied voltage12 V
Results
- Parallel resistance59.9768 Ω
- Series resistance790 Ω
- Current (parallel)0.20008 A
- Power dissipated2.4009 W
- Resistors entered3
Frequently asked questions
Why is parallel resistance lower?
Extra paths give current more ways to flow, reducing overall opposition.
What about two equal resistors?
Parallel resistance is exactly half of one of them.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.