NEC Box & Conduit Calc

NEC Box & Conduit Calc is the fastest, most accurate way to calculate box fill, conduit fill, required conduit size, and wire volume — all to the NEC (National Electrical Code).

Built for electricians, contractors, engineers, inspectors, and apprentices, it delivers instant, code-compliant results that save time on every job — right from your pocket, even offline.

Key Features

• Box Fill Calculator
– Device counts, equipment grounding, internal clamps
– All common box sizes and types
– NEC-compliant volume with clear breakdowns

• Conduit Fill Calculator
– EMT, PVC, RMC, IMC & more
– Multiple conductor sizes per conduit
– NEC fill percentages with instant pass/fail

• Required Conduit Size
– Enter your conductors, get the correct conduit size instantly
– See the next size up and down

• NEC Reference Tables
– Chapter 9 Tables 1, 4 & 5 at your fingertips
– Browse every NEC box and conduit size

• Accurate Wire Volume Data
– Built-in AWG volume reference for field, shop, and inspection

• Professional PDF Reports
– Export clean, shareable reports for your records or the inspector

• Clean, Simple Interface
– Designed for electricians under time pressure
– Easy to use with gloves
– Works fully offline

Perfect For
• Electricians
• Electrical contractors
• Students & apprentices
• Inspectors
• Engineers & designers

Download now and get code-compliant fill calculations in seconds — on every job.