First unit: kilometer (km) is used for measuring length. Second: inch (in) is unit of length. The inches unit number 39,370.08 in converts to 1 km, one kilometer. It is the EQUAL length value of 1 kilometer but in the inches length unit alternative. How to convert 2 kilometers (km) into inches (in)? Is there a calculation formula? First divide the two units variables. Then multiply the result by 2 - for example: