Instant Resistivity → Conductivity Calculator
Enter a material resistivity value (ρ) and this tool will calculate conductivity (σ) using the reciprocal relation: σ = 1/ρ.
Formula: σ = 1 / ρ | where ρ is resistivity and σ is conductivity.
What this calculator does
This resistivity to conductivity calculator converts a known resistivity value into conductivity in one click. In materials science, electronics, and electrical engineering, these two properties describe how easily electric current moves through a material.
Resistivity and conductivity are reciprocals, so when one goes up, the other goes down. That simple relationship makes quick conversion useful when comparing materials like copper, aluminum, silicon, water, and electrolytes.
How to use the calculator
- Enter the resistivity value (ρ).
- Select the resistivity unit: Ω·m, Ω·cm, or µΩ·cm.
- Choose the output conductivity unit: S/m or S/cm.
- Click Calculate Conductivity to view the result instantly.
The core formula
Resistivity to conductivity relationship
The conversion is:
σ = 1 / ρ
- σ = conductivity (S/m)
- ρ = resistivity (Ω·m)
If your resistivity is not in Ω·m, convert it first:
- 1 Ω·cm = 0.01 Ω·m
- 1 µΩ·cm = 1×10-8 Ω·m
- 1 S/cm = 100 S/m
Worked examples
Example 1: Copper
Copper resistivity at room temperature is roughly 1.68×10-8 Ω·m. Conductivity is 1 / (1.68×10-8) ≈ 5.95×107 S/m.
Example 2: Seawater
A typical seawater resistivity might be around 0.2 Ω·m. Conductivity is 1 / 0.2 = 5 S/m.
Example 3: High-purity water
Ultrapure water can be around 18.2 MΩ·cm. Convert first: 18.2×106 Ω·cm × 0.01 = 1.82×105 Ω·m. Then conductivity is 1 / 1.82×105 ≈ 5.49×10-6 S/m.
Typical values for common materials
| Material | Resistivity (Ω·m) | Conductivity (S/m) |
|---|---|---|
| Silver | 1.59×10-8 | 6.29×107 |
| Copper | 1.68×10-8 | 5.95×107 |
| Aluminum | 2.65×10-8 | 3.77×107 |
| Seawater | ~0.2 | ~5 |
| Distilled Water (approx.) | ~1×105 | ~1×10-5 |
Common mistakes to avoid
- Mixing resistance and resistivity: resistance depends on geometry; resistivity is an intrinsic material property.
- Using wrong units: Ω·cm and Ω·m differ by a factor of 100.
- Ignoring temperature: metal resistivity changes with temperature, so conductivity does too.
- Using zero or negative values: resistivity must be positive in this context.
FAQ
Is conductivity just the inverse of resistivity?
Yes. As long as units are consistent, conductivity is the reciprocal of resistivity.
Can I use this for semiconductors and electrolytes?
Yes, but remember these materials can be strongly temperature-dependent and composition-dependent.
What if I only know resistance?
Use geometry to find resistivity first: ρ = R·A/L, where R is resistance, A is cross-sectional area, and L is length. Then convert ρ to conductivity using this calculator.
Final takeaway
This tool gives you a fast and reliable resistivity-to-conductivity conversion for engineering and lab work. Enter your value, choose units carefully, and use the result to compare material performance or validate calculations.