Johan Petter Johansson (December 12, 1853 – August 25, 1943), sometimes called JP, was a Swedish inventor and businessperson. He created a modern adjustable spanner, which he patented in 1891 and May 11, 1892. He held over 100 patents throughout his life.

He was born in Vårgårda, a town in western Sweden, as the oldest of six children in a family that farmed small plots of land. His first job was as an assistant operator of a steam engine at a local peat factory. At age 19, in 1873, he moved to Motala to work as a navvy, which was a type of laborer. After completing military service in 1874, he moved to Eskilstuna, where he worked for the Bolinder-Munktell factory. In 1878, he relocated to Västerås and found work at a mechanical workshop. Later, he worked as a blacksmith at a nearby farm.

At this time, Johansson decided to leave Sweden for the United States. This plan did not happen because he received a better job offer from his former employer, Munktells, which changed his decision.

In 1886, he started his own business and moved to Enköping, where he founded Enköpings Mekaniska Verkstad (the Mechanical Workshop of Enköping). The business became successful quickly. During this time, he invented the adjustable spanner and the plumber wrench. In 1890, B.A. Hjorth & Company agreed to sell his tools worldwide under the "Bahco" brand. Bahco tools are still being made today, with over 100 million wrenches produced.

In 1916, Johansson handed over his large business to his son, Hannes Brynge, and to B.A. Hjorth & Company. Later, he began experimenting with electrical devices and opened a new factory called Triplex in 1919. This factory made electrical pendulums and other equipment.

Johansson died at the age of 89 after working productively for most of his life.