Wire Size Calculator
Calculate the recommended wire gauge for your electrical installation
System and cable properties
How far is the cable run from its source to the furthest point?
Recommended wire size per cable
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How to Use This Calculator
1. Select Electrical System
Choose between DC/AC Single-phase or AC Three-phase based on your electrical system configuration.
2. Enter System Parameters
Input your source voltage, allowable voltage drop, and select your conductor material (copper or aluminum).
3. Specify Load and Distance
Enter the current draw of your load and the one-way distance from the source to the furthest point in your cable run.
4. Set Temperature Rating
Specify the maximum wire temperature rating based on your wire insulation type and environmental conditions.
5. Review Results
The calculator will display the recommended wire gauge (AWG), cross-sectional area, and wire diameter for your application.
Important Notes
Voltage Drop Considerations
The NEC recommends limiting voltage drop to 3% for branch circuits and 5% for feeders and branch circuits combined.
Conductor Material
Copper has lower resistivity than aluminum, allowing for smaller wire sizes. However, aluminum is lighter and less expensive for larger conductors.
Temperature Rating
Common wire temperature ratings include 60°C (140°F), 75°C (167°F), and 90°C (194°F). Higher ratings allow for greater current capacity.
Safety Factor
Always consult local electrical codes and a licensed electrician before proceeding with any electrical installation.
Disclaimer
This calculator provides estimates based on theoretical calculations. Actual wire sizing must comply with the National Electrical Code (NEC) and local electrical codes. Additional factors such as ambient temperature, conduit fill, and circuit protection must be considered. Always consult with a qualified electrician and obtain proper permits before performing electrical work.