What Does WD-40 Really Stand For? The Simple Explanation That Still Blows Minds

If you’ve ever grabbed a can of WD-40 to silence a squeaky hinge, loosen a stuck bolt, or fix something in a hurry, you’re not alone. WD-40 is one of those household products that feels almost magical. Yet for decades, many people used it without ever knowing what its name actually means.

And when they finally find out?
Mind blown.

The Meaning Behind WD-40
WD-40 stands for Water Displacement, 40th Formula.

That’s it. No mystery code. No hidden marketing trick.

WD = Water Displacement
40 = The 40th attempt
The product was developed in 1953 by chemist Norm Larsen and his team at the Rocket Chemical Company. Their goal wasn’t to create a household lubricant—it was to solve a very specific industrial problem.

Why “Water Displacement”?
The original purpose of WD-40 was to protect metal from rust and corrosion by driving away moisture. It was designed to coat metal surfaces and prevent water from sticking—especially important for aerospace components exposed to harsh environments.

In fact, WD-40 was first used to protect the outer skin of the Atlas missile, one of the earliest U.S. rockets.