NEC field math, instantly.
Five code calculators built for the jobsite. Live results, NEC table citations, and it all works with no signal.
Open Voltage Drop →Voltage DropNEC 215.2(A) · Ch.9 Tbl 8Wire AmpacityNEC Table 310.16Conduit FillNEC Ch.9 Tbl 1,4,5Box FillNEC 314.16Conduit BendingBox-offset & 90° stub
Calculators built for electricians
Fieldwatt puts the five calculations you actually reach for on a jobsite into one fast, mobile-first tool. Every result recomputes live as you type and cites the NEC table behind it. Once loaded, the calculators run completely offline — no signal needed in a basement, a tunnel, or a steel building.
- Voltage drop — keep runs under the 3% / 5% recommendation.
- Wire ampacity — size conductors off NEC Table 310.16.
- Conduit fill — smallest legal raceway for your wires.
- Box fill — does it all fit per NEC 314.16?
- Conduit bending — offsets, shrink, and 90° stub take-up.
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