Conduit Fill Calculator

Add the conductors going in the raceway, pick the conduit, and see the actual fill percent vs the NEC Chapter 9 Table 1 allowable. Include the EGC if there is one.

Conduit

Conduit type

Trade size

Conductors

Results

Total conductor count—

Total conductor area—

Conduit interior area (Table 4)—

Allowable fill (Table 1)——

Actual fill—

Status—

Last reviewed: April 2026

Tools we used or recommend for this work: a Klein conduit bender in the trade size this calc recommended, Milwaukee EMT cutters or a portable bandsaw for clean cuts, a Greenlee fish tape, and pulling lubricant for tight conduit fills (Polywater J or Ideal Yellow 77). Links may be affiliate-tagged where the brand has a program.

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