Electrical Calculators

Quick Access Tools

Quick Convert

Watts to Amps - Instant power to current conversion

EV Ready

EV Charger Sizing - Level 2 charger installations

Professional Use Notice

All calculators provide reference values based on NEC 2023 standards. Results must be verified by licensed electrical professionals before implementation. Local codes may have more restrictive requirements.

Core Wire Sizing Tools

FEATURED

Essential calculators for determining proper wire sizes based on current, voltage, and installation conditions

Wire Size Calculator

Determines wire gauge based on amperage, voltage, and distance

Voltage Drop Calculator

Calculates voltage drop percentage

Ampacity Calculator

Look up NEC Table 310.16 ampacity ratings with temperature and bundling adjustments

Ground Wire Size

Determines equipment grounding conductor size per NEC Table 250.122

Wire Resistance Calculator

Resistance per 1000 ft and power loss

Power Conversions

FEATURED

Convert between electrical units - watts, amps, volts, kilowatts, horsepower, and more

Watts to Amps

Convert power in watts to current in amps for any voltage

Amps to Watts

Convert current in amps to power in watts

Volts to Amps Calculator

Current from power and voltage

Ohm's Law Calculator

Complete Ohm's Law and power calculations - solve for V, I, R, or P

kW to Amps

Convert kilowatts to amps

kVA to Amps Calculator

Convert kVA to amps

BTU to Watts Calculator

Convert Btu/h, watts and tons

Advanced Calculators

Three Phase Calculator

Three-phase power and current calculations

Service Entrance Calculator

Size service entrance conductors

Low Voltage Calculator

12 V and 24 V DC wire size

Additional Resources

Wire Sizing Guides

Guides for common wire sizing scenarios and installations

View All Guides →

NEC Ampacity Tables

Complete NEC Table 310.16 ampacity ratings with temperature corrections

View Tables →