Millions of people keep a can of WD-40 in their garage or toolbox, but many are surprised to learn the meaning behind its iconic name.
WD-40 stands for “Water Displacement, 40th Formula.” The product was developed in 1953 by chemist Norm Larsen and the Rocket Chemical Company, which was tasked with creating a solution to protect missile components from rust and corrosion by displacing moisture.
According to the company’s history, the team tested numerous formulas before achieving success on their 40th attempt. That breakthrough formula proved highly effective at driving moisture away from metal surfaces and preventing corrosion—giving the product the name it still carries today.
Although originally designed for aerospace applications, WD-40 soon found countless everyday uses. Today, it is commonly used to loosen rusted bolts, lubricate squeaky hinges, protect metal from corrosion, and remove stubborn grime, making it one of the world’s most recognizable household maintenance products.
The next time you reach for a can of WD-40, you’ll know its name isn’t just a catchy brand—it tells the story of persistence, innovation, and the 40th formula that finally got the job done.
