Practical tools for measured work
Series and parallel resistance calculator
Calculate equivalent resistance for up to 200 resistors, including ideal short circuits.
Calculate the layout, check the diagram, then print the result for the shop or jobsite.
Separate nonnegative resistance values with spaces, commas or semicolons; up to 200 resistors.
How it works
Series resistance is the sum of all resistors. Parallel resistance is the reciprocal of the sum of reciprocal resistances. Two 8 Ω resistors give 16 Ω in series or 4 Ω in parallel. A zero-ohm branch shorts an ideal parallel network, giving zero equivalent resistance.
Current-input example
The result above uses these exact values. This snapshot is included when the page is printed so the output can be checked against the original measurements.
- Resistor values in ohms
- 8,8
Primary result: Series resistance: 16 Ω.
Before using the result
- Check the selected mode, units and input values before using the result.
- Read the assumptions and rounding rules; compare the worked example with your intended calculation.
- A numerical result does not supply missing context or change the stated limitations.
Limitations
All listed resistors must be entirely in series or entirely in parallel. Mixed networks require reducing subgroups separately. These ideal values exclude tolerance, temperature drift, lead resistance, power ratings and frequency-dependent impedance.
Frequently asked questions
What should I verify before using this result?
Check the input values, units, dates and assumptions. Compare the method and its stated limits with the source relevant to your task.
Why might the finished result differ?
Results depend on the entered data and the model’s assumptions. Rounding, changing conditions or omitted factors can affect the comparison. Read the limitations before using the result.
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