Ch 9 Table 4: Conduit Fill

Dimensions and Percent Fill of Conduit and Tubing (EMT Example).

Source: NEC 2020

The Math Shortcut

Use the Conduit Fill Calculator

Trade Size	ID (in)	100% Area (in²)	40% Area (in²)
1/2	0.622	0.304	0.122
3/4	0.824	0.533	0.213
1	1.049	0.864	0.346
1-1/4	1.380	1.496	0.598
1-1/2	1.610	2.036	0.814
2	2.067	3.356	1.342
2-1/2	2.731	5.858	2.343
3	3.356	8.846	3.538

Professional Usage

This data is provided for informational purposes only. Always verify with the latest edition of the National Electrical Code (NFPA 70) and consult with a licensed electrical professional or AHJ (Authority Having Jurisdiction) before performing any electrical work.

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