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Electrical Calculators

Browse 4 free electrical calculators with transparent formulas, worked examples, assumptions, and cited sources.

Electrical

4 calculators

  1. Recessed Lighting CalculatorEstimate a centered recessed-light grid from maximum spacing or an early lumen-and-beam planning model.
  2. Parallel Resistor CalculatorCalculate equivalent resistance, total current, and total power for ideal resistors connected in parallel.
  3. Conduit Fill CalculatorCheck common 2023 NEC EMT fill from THHN/THWN-2 wire sizes and quantities, or enter custom listed areas.
  4. Voltage Drop CalculatorEstimate conductor voltage drop and delivered voltage from current, length, material, and wire size.