Disclaimer

This site provides estimates for education and planning — not engineering advice.

Electrical wiring decisions affect fire and shock safety. The calculators here use standard published values (NEC Chapter 9 Table 8 resistance, Table 310.16 ampacity) and simplified, clearly-stated assumptions — they cannot account for every real-world condition: termination ratings, harmonics, voltage unbalance, soil thermal resistivity, local code amendments, equipment-specific requirements, or installation workmanship.

Before purchasing materials or installing wiring:

• Verify all sizing with the current NEC edition adopted in your jurisdiction and any local amendments.
• Confirm the design with a licensed electrician or professional engineer.
• Obtain required permits and inspections from your authority having jurisdiction (AHJ).

Use of this site is at your own risk, as set out in the Terms of Service.