Engineering

Free American Wire Gauge (AWG) calculator — look up wire diameter, cross-sectional area, and resistance; size wires by current and voltage drop; convert diameters to AWG; and calculate equivalent gauge for parallel wires.

Free American Wire Gauge (AWG) wire size reference table and calculator. Look up wire diameter, cross-sectional area, resistance, ampacity, skin depth, and breaking force for AWG 4/0 through AWG 40. Supports copper, aluminum, and 6 other materials.

Free electricity bill calculator — estimate your monthly electricity costs by appliance, calculate bills from meter readings, compare electricity rates, and track annual CO2 emissions.

Free Resistor Color Code Chart and Calculator — decode 3-band, 4-band, 5-band, and 6-band resistors instantly. Includes reverse lookup, parallel/series calculator, SMD decoder, and full IEC 60062 reference table.