420: Meaning and How it Became Weed Day

Happy 420! If you are reading this on the day that this post was published, then the date is April 20th, or 4/20 (pronounced four-twenty). If you smoke marijuana, then you probably know that 4/20 is Weed Day. For some reason, every year on April 20th, marijuana smokers from all over the world gather around and celebrate. Some places will even host events dedicated to celebrating this day. But what is the reason for celebrating 420? Why is April 20th Weed Day? Well, let’s find out!

One of the biggest myths about 420 is that it originated from a police code dating back to the 1970s in California. This police code was used when someone was caught in the act of smoking marijuana. This myth, however, is incorrect. But the part about being in the 1970s and California is true.


So where did 420 originate? It originates back to 1971 in San Rafael, California. Five high school students were on a hunt for some marijuana plants that had been abandoned. They called themselves the Waldos because they hung out at a wall outside of their school, San Rafael High School. They were all in sports, so one day after practice they decided to meet up at the statue of Louis Pasteur at 4:20 p.m. to search for the plants.

Before meeting up at this statue, they would use the codeword “420 Louis” during school to remind each other about the plan. The first attempt was a failure. So were some attempts after that. But they continued to meet at the statue at 4:20 p.m. to recover some free weed. Every time they met at the statue, they would smoke before they went on the hunt. After many failed attempts, the codeword was shortened to only “420”. At this time, nobody knew what they were talking about whenever they would say “420”. But this word would turn into a nickname for marijuana for many teens across the United States, and eventually the rest of the world.

How It Spread

But how did the term “420” spread from a few stoners in California to the whole world? Well, that was with the help of an American rock band known as The Grateful Dead. The band moved to Marin County in the late 1960s, just a few blocks away from San Rafael High School. One of the Waldos’ fathers took care of The Grateful Dead’s real estate.

The Grateful Dead and the Waldos used to smoke together. This is how the Waldos spread the word “420” to the band. As the Grateful Dead went on many tours throughout the 1970s and 1980s, they spread the word across America. But it would not be until the 1990’s that “420” would reach a global scale.

Going Global

In May 1991, twenty years after the Waldos created the codeword “420,” the High Times magazine released an article on how 420 originated. They even bought 420.com in the early 1990s. High Times had a connection with The Grateful Dead, which is where they sourced the article. Below is the cover of the May 1991 issue of High Times magazine, which included 420 articles:

However, this article stated that The Grateful Dead established the phrase “420.” Within a few years of the article being published, the Waldos started noticing people using it outside of California, and even outside of the United States. Once they found out about the High Times article, which was very popular at the time, they decided to get in touch with the High Times.

In 1997, the Waldos met up with High Times to convince them that they established the phrase “420.” They brought to proof with them, letters from the 1970s that included them using 420. High Times believed them, but they never made any money off of it. Although, in 2008, High Times flew one of the Waldos out to a 420 event in Amsterdam, on April 20th (of course).

Since the High Times article was published, there have been many other instances of the phrase “420” being used. For example, when California law voters approved of medical marijuana use in the state, the bill was named SB420.


As for the meaning of 420, if you cannot tell from the story above, it is used as another name for marijuana. From a codeword for a plot on some free weed to another name for weed, 420 has come a long way!

Today, thousands of people worldwide celebrate April 20th as Weed Day. So if you enjoy smoking marijuana, then celebrate by sparking up! If you enjoyed this story, share it with some friends so they can learn the true meaning of 420.

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Evan Weston

Evan Weston is a contributor to Reefer Posts, a growing community for exploring the developing market of Cannabis and CBD-related products. He spends a lot of time researching the development of health-related products that utilize Cannabis and CBD oils. He also keeps tabs on the developing legal environment regarding medical, recreational cannabis use, and production.

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