Electrical Calculators

Estimate household appliance electricity use, monthly energy cost and yearly bill for US or India rates, including India slab tariffs.

Decode 4-band and 5-band resistor colour codes, encode resistance values and check common resistor colour charts.

Size AC power cables to IEC 60364: design current, derating for ambient temperature and grouping, ampacity…

Free voltage drop calculator with NEC and IEC modes: get percent drop, wire size in AWG or mm², power loss…

Calculate DC cable voltage drop from system voltage, current, cable length, conductor material and cable…

Select a distribution transformer kVA rating from connected load, diversity and future spare capacity, with…

Calculate earth electrode resistance, single-rod and multi-rod grounding resistance, the earthing conductor…

Calculate the ampacity of ACSR, AAAC and AAC overhead conductors such as DOG, PANTHER, RABBIT and WEASEL…

Convert American Wire Gauge to square millimetres and back — with conductor diameter, exact cross-sectional…

Work out the wire size you need for any AC or DC circuit from load, run length and allowable voltage drop —…

Printable AWG to mm² wire gauge chart with conductor diameter, cross-section, resistance per km and typical…

Calculate electrical power, current, voltage, kW, kVA, kVAR and power factor for single-phase and three-phase…

Calculate capacitor bank kVAR required for power factor correction, capacitor capacitance, corrected power…

Calculate a suitable preliminary MCB rating from load current, kW, kVA or voltage, with power factor,…

Calculate a preliminary fuse size for AC or DC circuits from load current, kW, kVA or voltage, with power…

Convert kVA to kW, kW to kVA, kVA to amps or amps to kVA for single-phase and three-phase AC systems using…

Check the current capacity of 1.5, 2.5, 4, 6 and 10 sq mm copper or aluminium wire with installation,…

Calculate estimated single-phase or three-phase motor full-load current from horsepower, voltage, efficiency…

Find the NEC reference conductor size for a 100, 125, 150 or 200 amp service, compare copper with aluminium…

Convert watts to amps for DC, single-phase AC and three-phase AC supplies. Enter power, voltage and power…