E-Calc USA

E-Calc USA 2026: The Ultimate NEC Companion Stop flipping through code books and start calculating with precision.

E-Calc USA 2026 is the definitive electrical resource for professionals who demand more than just simple formulas. Designed specifically for electricians, engineers, and contractors, this app provides instant, accurate results based on the 2026 National Electrical Code (NEC).

While other apps stop at basic math, E-Calc USA handles the heavy lifting—delivering code-compliant wire sizing, conduit capacities, fusing, and bonding requirements in seconds.

Professional Features for the Field

Advanced Motor & Transformer Tools

Motor Loads: Get instant results for maximum overcurrent, overload protection, minimum wire size, conduit size, and bond wire requirements.

Transformers: Calculate FLA, pipe size, fuse/breaker ratings, and bond sizing for both primary and secondary systems.

Precision Wire & Conduit Sizing

Ampacity & Derating: Calculate allowable ampacity for any wire type or complex derating scenario.

Conduit Fill: Quickly find the maximum number of similar-sized wires for any given pipe.

Expansion & Spacing: Calculate linear expansion for conduits and required strap spacing.

Complex Calculations Made Simple

Voltage Drop: Solve complicated runs easily. Get results for percentage drop, maximum run lengths, and wire sizing, with full support for derating.

Box Fill: Accurate calculations in both mL and cubic inches.

On-Site Utilities & Reference

Panel Legends: Create custom, professional panel legends and print them directly to scale.

Torque Settings: Access recommended torque settings for a wide variety of lugs and terminations.

NEMA Reference: Quickly find NEMA codes and receptacle specifications.

Built for Your Workflow

Save & Share: Every calculation is saved and can be printed or shared with your team or inspectors.

Universal Access: Buy once and run E-Calc USA on your iPhone, iPad, and Mac.

Integrated Tools: Includes a comprehensive unit converter, Ohm’s Law calculator, and voltage unbalance tool.

Whether you are in the office designing a system or on-site during an inspection, E-Calc USA ensures you have the power of the National Electrical Code right in your pocket.

Download E-Calc USA today and work smarter.