Conduit Fill Calculator (NEC)
Code-compliant wire fills, instantly.
Conduit & Wire Specs
Conductors
NEC Compliance Check
Current Fill
NEC Compliant
Max Capacity
Max allowed for this size/type
Calculation Details
- 1 wire: Max 53% fill
- 2 wires: Max 31% fill
- Over 2 wires: Max 40% fill
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Conduit Fill Calculator (NEC) for electrical contractors
Conduit Fill Calculator (NEC) helps electrical contractors ensure NEC compliance. Enter conduit size and wire types and get code-compliant fill percentages you can use immediately in your bid or project file.
Used by contractors across California, Texas, Florida, New York, and Illinois, with active users in Los Angeles, Houston, Dallas, Chicago, Phoenix, Atlanta, Seattle, and Denver.
Quick answer: what does this tool do?
Calculate NEC conduit fill quickly for any conduit size.
How should I apply the results?
Use results to size conduit and avoid code issues.
Is this suitable for public bids?
Yes. The inputs align with typical DOT, municipal, and federal bid requirements.
What keywords does this tool target?
conduit fill calculator, NEC wire fill
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