Our NEC Conduit Fill Chart calculates THWN and THHN wire fill for EMT, IMT, rigid metal, or flexible metal conduit pipe using conduit trade size and AWG or MCM wire size.

CONDUIT FILL TABLES – NEC TABLE C CONDUCTOR SIZE – AWG / kcmil – THHN / THWN SIZE 14 12 10 8

The app will calculate the conduit fill percentages and jam probability for multiple conductors per NEC® Guidelines. Simply enter the conduit type and size, then specify your conductors.

Aug 2, 2025 · Discover NEC-compliant conduit fill charts for EMT, IMC, Rigid, and Flexible Metal Conduits. Downloadable tables, size-by-size breakdowns, and manufacturer-supplied resources for …

Oct 27, 2025 · Master conduit fill calculations with our complete NEC guide including fill charts, wire capacity tables, and step-by-step examples. Learn proper conduit sizing for electrical installations.

The NEC sets standards for the percent of volume that can safely be put into conduit. The below chart is from Table 1 in Chapter 9 of the National Electric Code.

Apr 20, 2025 · Below are NEC-compliant tables summarizing the most commonly used conduit types and conductor sizes. These serve as references for compliant cable fill calculations.

Oct 1, 2025 · For conduit fill specifically, Chapter 9 contains several interconnected tables that work together as a complete system.

This conduit fill table can help you make wiring decisions. Use it to determine how many wires your conduit tubing can safely contain. The horizontal numbers at the top of the graph refer to the size …

For licensed electricians, correctly calculating conduit fill is a fundamental skill that ensures safety, code compliance, and professional-quality work. The National Electrical Code (NEC) provides a …