Electrical calculators: choose the right tool
Calculate current, convert motor power and compare wire sizes. Start with the quantity you already know, then select the circuit type and voltage in the calculator.
Power and current
kW to amps — Convert real power to current for DC, single-phase or three-phase circuits.
kVA to amps — Use apparent power and voltage to calculate current.
VA to amps — Find current on the selected transformer winding.
Three-phase current — Calculate balanced three-phase current with power factor and, where needed, efficiency.
Wire sizes, voltage and motors
mm² to AWG — Compare wire cross-sectional area and American Wire Gauge sizes.
Line-to-line and line-to-neutral voltage — Convert voltages in a balanced wye system.
kW to horsepower — Convert motor power units and compare common ratings.
CV to HP — Convert metric horsepower to mechanical horsepower.
Before calculating
kW or kVA? kW measures real power; kVA measures apparent power. Their relationship depends on power factor.
Which voltage? For a balanced three-phase current calculation, use line-to-line voltage. For a transformer, match the voltage to the winding whose current you want.
Motor power? Distinguish electrical input from mechanical output. Efficiency is needed when converting shaft output to electrical input.
Wire conversion? An AWG/mm² comparison gives area, not a cable’s permitted current. Cable selection also depends on installation conditions and applicable rules.
Continue by electrical task
Open a focused directory to choose the next calculation.
Current calculations — Start from kW, kVA, VA or horsepower.
Power and energy — Distinguish kW, kVA, kWh and simultaneous loads.
Wire size and conductor conversions — Compare area, ampacity and cable properties.
Voltage drop — Choose a method for AWG/kcmil, mm² or cable impedance.
Transformer calculations — Match current and voltage to each winding.
UPS and battery calculations — Separate capacity, input current and runtime.
Browse all electrical calculators
Quickly estimate I²R losses with our feeder copper loss calculator to get watts and percent loss results for any load current. Perfect for engineers and facility managers, it helps you pinpoint energy waste and make smarter decisions fast.
Quickly estimate line losses and ensure your circuits run efficiently with our instant voltage drop calculator for 1‑phase and 3‑phase systems, Cu/Al conductors, and AWG/kcmil sizing (Volts & %). Save time and avoid costly mistakes with clear results in volts and percent.
Get instant, code-compliant wire sizing with our free conductor size calculator—designed to handle continuous and noncontinuous loads under NEC 210.19/215.2 with clear, professional guidance.
Estimate wire size from load current, ampacity, insulation and terminal ratings, ambient temperature and conductor count. Copper and aluminum supported.
SPD placement around ATS is a critical decision for emergency systems. Learn when line-side protection beats load-side so you can maximize uptime and safety.