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Electrical Calculators
Built for working electricians. All calculations follow NEC standards.
Voltage Drop Calculator
Check NEC 3% and 5% limits for any wire run. Enter voltage, amps, length, and gauge.
Wire Sizing Calculator
Get the correct AWG for any load. Accounts for 125% continuous load rule and voltage drop.
Conduit Fill Calculator
Verify NEC Chapter 9 40% fill limit. Add multiple wire gauges and counts.
Box Fill Calculator
Calculate minimum box volume per NEC 314.16. Includes devices, clamps, and grounds.
Panel Load Calculator
Add up circuit loads, apply NEC demand factors, and find the right panel size.
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