When to use this calculator
Estimate conductor resistance from material resistivity, length and area. Uses entered resistivity at a stated temperature; the length is the total conductor path being modelled.
Explore the dc circuits & components calculators for other questions in this topic. For a related calculation, use the AC Apparent Power Calculator: Calculate apparent power from single-phase RMS voltage and current.
PUTTING IT INTO PRACTICE
Wire Resistance: a worked example
The values below are an illustrative example, not a recommendation. Replace them with measurements or assumptions that match your question.
| Input | Example value |
|---|---|
| Resistivity (Ω·m) | 1.680000e-8 |
| Conductor length (m) | 10 |
| Cross-sectional area (mm²) | 2.5 |
| Result | 0.0672 Ω |
- Check the input labels and enter the example values above.
- Apply the relationship: Resistance = resistivity × length/(area×10⁻⁶).
- The result is 0.0672 Ω, rounded for display.
How to interpret your result
Uses entered resistivity at a stated temperature; the length is the total conductor path being modelled.
Ideal component models omit tolerances, heat and parasitic effects. Distinguish nominal energy from usable energy for batteries. Component ratings and installation requirements need separate manufacturer and design checks.
Frequently asked questions
Can these calculations select a safe installation rating?
No. They explain ideal relationships and do not include every thermal, protective or regulatory requirement.
When is the wire resistance calculator useful?
Estimate conductor resistance from material resistivity, length and area. Uses entered resistivity at a stated temperature; the length is the total conductor path being modelled.
How do I use the wire resistance calculator?
Enter resistivity (ω·m), conductor length (m), cross-sectional area (mm²). The result updates automatically. Use the units shown beside each input; the example values illustrate the method.
Which formula does this calculator use?
Resistance = resistivity × length/(area×10⁻⁶).
What should I check before using the result?
Uses entered resistivity at a stated temperature; the length is the total conductor path being modelled.
How are results rounded?
Scalar numbers display up to six decimal places, with scientific notation for very large or small values. Text, fraction, date and schedule outputs use the format described on the tool. Intermediate calculations use JavaScript floating-point arithmetic. Keep sensible precision for your measurements.
Calculators Map editorial process · Updated · Methods and limitations