Amp to Wire Size Calculator
Quick amp-to-AWG planning lookup by conductor material and wiring method.
Electrical Calculators
Electrical calculators for circuit math, transformers, power factor, kVA and current conversion, conductor planning, voltage drop, raceway and box fill, load conversion, breaker estimates, and generator sizing.
CalcShed's electrical calculators cover circuit math, kVA and current conversion, power factor, transformer planning, conductor sizing, voltage drop, conduit and box fill, cable-tray checks, equipment-load conversion, breaker planning, and generator sizing. The tools surface the assumptions that change the result instead of hiding them behind one generic answer. Code-dependent calculators identify their NEC scope; formula and equipment-planning tools keep standard electrical math separate from code compliance. Verify the code edition adopted in your jurisdiction, local amendments, equipment listings, and manufacturer instructions before installed work.
Box Fill Calculator
Calculate box volume allowances for conductors, devices, clamps, and grounds under NEC 314.16.
Breaker Size Calculator
Estimate a standard OCPD planning rating from separate continuous and noncontinuous current, with optional conductor screening.
Cable Tray Fill Calculator
Scoped NEC 392.22 cable-tray checks plus a separate geometry-only occupancy mode using actual cable outside diameters.
Conduit Fill Calculator
Check mixed-conductor raceway fill, short-nipple limits, and minimum conduit size.
Electrical Load Calculator
Combine up to six equipment loads and convert W or VA to current, kW, and kVA.
Generator Size Calculator
Build a generator load list and compare continuous running demand with staggered-start or simultaneous-start surge targets.
kVA to Amps Calculator
Convert kVA and voltage to amps or reverse amps to kVA for single-phase and balanced three-phase systems.
Ohm's Law Calculator
Solve voltage, current, resistance, and power from any two known values.
Power Factor Calculator
Solve power factor, kVA, kVAR and phase angle or calculate power-factor correction kVAR and current reduction.
Transformer Calculator
Calculate transformer currents, required kVA, connection-aware winding ratio, and optional fault current from nameplate impedance.
Voltage Drop Calculator
Check voltage drop, find a voltage-drop-only conductor size, or solve maximum one-way distance for single-phase/DC or balanced three-phase circuits.
Watts Amps Volts Calculator
Solve watts, amps, or volts for DC, single-phase AC, or balanced three-phase AC with power factor and kVA.
Wire Size Calculator
Plan AWG from ampacity, ambient temperature, conductor count, and optional voltage-drop sizing.
Frequently Asked Questions
What electrical calculators are available?
CalcShed currently has 14 electrical tools: Amp to Wire Size, Box Fill, Breaker Size, Cable Tray Fill, Conduit Fill, Electrical Load, Generator Size, kVA to Amps, Ohm's Law, Power Factor, Transformer, Voltage Drop, Watts/Amps/Volts, and Wire Size.
Are the results based on the NEC?
Some are. Conduit Fill, Box Fill, Wire Size, and the scoped Cable Tray Fill modes identify the NEC provisions or data they rely on. Pure formula tools such as Ohm's Law and Watts/Amps/Volts use standard electrical equations. Cable Tray Fill also includes a separate geometry-only mode that makes no NEC compliance claim. Always verify the edition adopted in your jurisdiction and local amendments.
Can I use these for permitted electrical work?
Use the calculators for planning, cross-checking, and estimating. Final installed work must account for the locally adopted code edition, amendments, equipment ratings, installation conditions, and AHJ requirements; have permitted work verified by a qualified electrical professional.
Why does voltage drop matter?
Voltage drop reduces the voltage delivered to the load and can affect equipment performance. Common NEC informational-note guidance uses about 3% for a branch circuit and 5% for feeder plus branch total, so long runs can require a larger conductor even when ampacity alone is adequate.