Electrical Calculators

Free tools for voltage drop, wire sizing, conduit fill, and more. For estimation only. Verify with the current NEC and a licensed electrician.

Voltage Drop

Wire & Ampacity

Conduit & Box Fill

Load & Service

Motors & Transformers

Conversions

Reference charts

Use these as a starting point only. We are not liable for any decisions you make or how you use these tools in the real world. Verify with the current NEC and a licensed electrician before any real installation. Full disclaimer