Conduit Fill Calculator by Wire Size and Type
Conduit fill by wire size and type starts with each conductor area, count and raceway area. The working calculator compares the selected raceway against NEC-style fill limits.
conduit fill calculator by wire size and type conduit fill by wire size calculator raceway fill calculator multiple cable sizes
Raceway fill
fill_percent = 100 * conductor_area_total / raceway_area
Mixed conductor rows
- Choose the conductor insulation/type data.
- Enter conductor count by size.
- Select raceway trade size.
- Compare fill percent with the applicable fill limit.
Installation caution
Raceway fill is only one check. Ampacity adjustment, pull tension, sidewall pressure, box fill and local code still need separate review.
Related pages
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