WD-40 Is Named After the 40th Try

In 1953 a small company in San Diego set out to solve a problem for the aerospace industry. Rocket Chemical Company had a staff of three and a small lab. It wanted to make a line of solvents and degreasers that would stop metal from rusting.

The method was water displacement: a coating that pushes moisture off a surface and keeps it from coming back. It was harder to get right than it sounded. The team kept a lab book, numbered its attempts, and kept going.

1953: Formula number 40

The 40th formula worked. The company has explained that the product’s name came straight from that lab book: Water Displacement, 40th attempt. The name came from a notebook, not a marketing meeting.

Rocket Chemical Company was founded on September 23, 1953, by Norman B. Larsen, Gordon Dawson and John B. Gregory, according to the company’s history. Larsen, a chemist, is the person the company credits with developing the formula.

That credit is not undisputed. Wikipedia notes that Iris Engstrand, a historian of San Diego at the University of San Diego, has written that the formula was developed by Iver Norman Lawson, who worked on it at home and sold it to Rocket Chemical for $500. In her account, Larsen’s contribution was the idea of putting it in aerosol cans and selling it to the public. The formula itself was never patented and has been kept as a trade secret.

A missile’s skin

The first commercial customer was Convair, an aerospace contractor in San Diego that was part of General Dynamics. Convair used the product to protect the outer skin of the Atlas missile from rust and corrosion. On the Atlas, that thin steel skin was also the wall of the missile’s fuel tanks, so corrosion was a serious problem.

The product worked so well, the company says, that some Convair employees started sneaking cans out of the plant to use at home. The missile coating had a second market that nobody had planned for.

1958: Into the shops

Larsen saw what the employees had seen. He experimented with packing the product in aerosol cans, and in 1958 WD-40 went on sale in stores in San Diego.

Selling it was a matter of persistence too. Salesmen took cans out in their cars to sporting goods and hardware stores around San Diego. By 1960, SlashGear reports, seven traveling salesmen were selling a little under 50 cases of cans a day.

It was enough. In 1965, according to the International Directory of Company Histories, Rocket Chemical stopped making its other products to concentrate on WD-40. In 1968 kits containing the spray were sent to American soldiers in Vietnam, who used it to protect their equipment from the damp. In 1969 the company renamed itself after its only product: WD-40 Company.

One can, many years

The company grew slowly and steadily on a single formula. In 1993, its 40th year, it passed $100 million in annual sales.

In the fiscal year to August 31, 2025, WD-40 Company reported net sales of $620 million. It now sells other brands and specialist versions, but the original blue and yellow can is still most of the business: WD-40 Multi-Use Product accounted for $478 million of those sales.

What the record shows

• The name records the failures. A product called “40th formula” is also a record of 39 that did not work.
• Users find uses the makers did not plan. Workers carrying cans home revealed a market far bigger than missiles.
• One product can be enough. The company dropped everything else in 1965 and later took its product’s name.
• A secret can protect better than a patent. The formula was never patented, so it never had to be published, though that also left the question of who invented it open.

Other products in this archive found their real market only after they had been made for something else. Bubble Wrap was meant to be wallpaper, and Play-Doh was sold to clean it.