How it works
Add nonnegative ideal resistor values connected in series. Values must all use ohms.
R = R₁+R₂+…
Worked example
Show example inputs and result
Resistances in ohms: 100 220 330.
- Equivalent resistance
- 650 Ω
Questions and answers
Why are some results rounded?
Results display up to 8 decimal places. Calculations use the unrounded values; very small values use scientific notation. JavaScript floating-point arithmetic can introduce tiny rounding differences.
Are my inputs sent to a server?
The calculator processes inputs in your browser. Its code does not send your values to a server.
Method reviewed: October 8, 2026 · Methods & accuracy