The Electro Info application is designed to calculate the cross-section of cable conductors from 1.5 mm2 to 120 mm2 depending on the current or load power, type of alternating current (single-phase or three-phase), conductor material (copper or aluminum) and laying method (“hidden” or “open” ), taking into account the power factor cosφ. The calculation of the cross section is advisory. The appendix also gives recommendations on choosing the type of cable depending on the purpose and method of laying the cable, shows the advantages and disadvantages of various types of cables, and recommendations for choosing circuit breakers for a household network.