Electrical
Electrical load demand, home power consumption, utility bill estimation, generator and inverter sizing, battery backup, and cable gauge calculators.
Free online general tools.
Appliance Electricity Cost
Calculate the exact operating cost per hour, per day, per month, and per year for any specific household appliance.
Appliance Wattage Calculator
Calculate appliance wattage from voltage and current draw, plus estimated monthly kWh usage.
Battery Backup Calculator
Calculate battery bank storage capacity in Amp-hours (Ah) and Kilowatt-hours (kWh) for emergency home backup or off-grid solar storage.
Battery Capacity Calculator
Calculate the required battery capacity (Ah) to power a load for a desired runtime.
Battery Charging Time Calculator
Calculate how long it takes to fully charge a battery based on capacity, charger current, and charging efficiency.
Battery Energy Calculator
Calculate total stored energy in watt-hours (Wh) and kilowatt-hours (kWh) from battery capacity and voltage.
Battery Runtime Calculator
Calculate how long a battery will power a given load based on capacity, voltage, depth of discharge, and system efficiency.
Cable Resistance Calculator
Calculate cable/conductor resistance based on material resistivity, length, and cross-sectional area.
Cable Size Estimator
Estimate recommended electrical wire gauge (AWG or mm²) based on current amperage, circuit length, voltage drop, and conductor material.
Circuit Breaker Size Calculator
Calculate the correct circuit breaker size for a continuous load using the NEC 125% rule.
Current Calculator
Calculate electrical current using Ohm's Law: I = V / R, from voltage and resistance values.
Electrical Load Calculator
Calculate total residential or commercial electrical demand in watts and amperes based on NEC (National Electrical Code) diversity demand factors.
Electrical Power Calculator
Calculate real power (watts) and apparent power (VA) from voltage, current, and power factor.
Electricity Bill Estimator
Estimate your monthly electricity bill based on tiered utility rates, flat monthly service fees, fuel adjustments, and peak time-of-use tariffs.
Fuse Size Calculator
Calculate the recommended fuse size for a load current using an adjustable safety multiplier.
Generator Fuel Calculator
Calculate fuel consumption for a generator based on load, runtime, and specific fuel consumption rate.
Generator Size Calculator
Size portable backup and whole-house standby generators factoring in running watts and motor surge starting wattage requirements.
Home Power Consumption Calculator
Calculate monthly and annual kilowatt-hour (kWh) electricity usage across lighting, HVAC, refrigeration, and home electronics.
Inverter Battery Calculator
Calculate the battery bank capacity (Ah) needed to power an inverter load for a desired backup time.
Inverter Size Calculator
Size DC-to-AC power inverters for RVs, off-grid cabins, and backup systems based on continuous AC load and surge power.
LED Savings Calculator
Calculate annual energy and cost savings from switching incandescent bulbs to LED equivalents.
Motor Current Calculator
Calculate full load motor current for single-phase or three-phase motors from power, voltage, power factor, and efficiency.
Motor Efficiency Calculator
Calculate motor efficiency as the ratio of mechanical output power to electrical input power.
Power Factor Calculator
Calculate power factor, phase angle, and reactive power (kVAR) from real power (kW) and apparent power (kVA).
Resistance Calculator
Calculate electrical resistance using Ohm's Law: R = V / I, from voltage and current values.
Single Phase Power Calculator
Calculate single-phase electrical power in watts and kilowatts from voltage, current, and power factor.
Solar Panel Size Calculator
Calculate the total solar photovoltaic (PV) array wattage required to generate your desired daily and monthly kilowatt-hour energy needs.
Three Phase Power Calculator
Calculate three-phase electrical power in watts and kilowatts from line voltage, line current, and power factor.
Transformer Size Calculator
Calculate transformer kVA rating for single-phase or three-phase systems from voltage and current.
Transformer Turns Ratio Calculator
Calculate transformer turns ratio and secondary current from primary and secondary voltage.
UPS Runtime Calculator
Calculate battery backup runtime in minutes for uninterruptible power supplies (UPS) based on connected computer load, VA rating, and battery voltage/Ah.
Voltage Calculator
Calculate voltage using Ohm's Law: V = I × R, from current and resistance values.
Wattage Calculator
Calculate electrical power in watts from voltage and current using the formula P = V × I.