An alarm clock displays the time 4:20 PM

Smoke King Guide to the Origin of 420

The origin of 420 has become a deeply ingrained part of cannabis culture. Even to nonsmokers, the number is synonymous with marijuana. But where did it come from?

Different theories formed over time. Some are so far-fetched that they must have come from all-night smoking sessions, but there is undeniable proof that these dank digits have a direct source.

Read on to dig deeper into this hazy legend and clear the air on the history of 420.

420 Myths

Before we get to the truth, let’s debunk a few myths. These rumors represent some of the most popular stories regarding the origin of 420.

Police Code

The idea that this numeric slang originated from a police code makes sense on paper. If the Los Angeles Police Department used 420 for “marijuana smoking in progress,” this case would be closed. There’s just one problem; 420 was never related to weed infractions in California.


Some claim that 420 is the number of chemical compounds in cannabis. It’s hard to argue with science, which is why we know this theory is wrong. Studies actually show there are over 500 chemical compounds in pot.

Bob Dylan

Some music fans will tell you that Bob Dylan’s 1966 single “Rainy Day Women No. 12 & 35” spawned 420. After all, the chorus does say, “Everybody must get stoned.” And when you multiply 12 by 35, you get 420.

However, that math doesn’t add up to us. Plus, the singer claimed in a Rolling Stone interview the song was a reference to the Bible.

The Real History of 420

Man smokes joint to celebrate 420


To find the truth, we must go on a strange journey involving a treasure map, an abandoned pot farm, and the Grateful Dead. And it all started with a group of San Rafael High School students who called themselves the Waldos.

X Marks the Spot

The origin of 420 began in 1971 after a friend handed a member of the Waldos a map. Supposedly, it would reveal the location of an abandoned plot of land where marijuana plants were growing. A member of the Coast Guard once tended to it but had since abandoned his cannabis post.

The search was on. Every afternoon after football practice, the Waldos would meet at a statue of Louis Pasteur outside the school at 4:20 PM. They would say “420 Louie” as they passed in the hallway to remind each other.

They never did find that treasure, but they unknowingly discovered something even greater. Soon, they would drop the “Louie” from their clandestine communication, and their slang for a legendary plot of pot became the root of the history of 420.

The Waldos’ claim this is just a tall tale between old friends, but they have postmarked letters showing they indeed used the term in the ‘70s.

Spread by the Dead

Several members of the Waldos had connections to members of the Grateful Dead, and they soon became friends with the band’s bassist, Phil Lesh. As a result, they frequently found themselves at the Winterland concert venue in San Francisco, rolling joints with the band.

Though the origin of 420 took shape in the halls of San Rafael High, its spread began at Winterland. Soon after, friends of the Waldos and the Grateful Dead began using the term 420, too. One of the Waldos became a roadie for the Dead, a notoriously hard-touring band. The inside joke had now officially left their inner circle and was about to hit the road.

High Times

High Times reporter Steve Bloom first came across the term 420 in 1990. A hippie handed him a flyer as he shuffled through a crowd waiting to see a Grateful Dead concert in Oakland, California. It read, “We are going to meet at 4:20 on 4/20 for 420-ing.”

Bloom had the High Times run the flyer, introducing a world of stoners to the Waldos’ jargon—and the concept of a holiday surrounding it. In 1998, the High Times would tip their cap to the California buds, ordaining the Waldos as the inventors of 420 in the pages of their magazine.

From Slang to Holiday

Four hands hover over a table preparing cannabis for 420


Despite the widespread adoption of the term by cannabis connoisseurs, the history of 420 was just beginning. What was once lingo used in locker rooms and counter-cultural gatherings quickly worked its way into the mainstream media through subtle references.

420 in the Media

From its humble origins, 420 was soon seen on screen across the world. In Quentin Tarantino’s 1994 film Pulp Fiction, many shots include clocks intentionally set to 4:20. Meanwhile, on national daytime TV, a contestant on The Price Is Right only placed bids of $420. Oddly, even the ‘90s Nickelodeon cartoon Rocko’s Modern Life got in on the fun by featuring a clock reading 4:20.

Back to School

Fittingly, 420 found its way back to school. College students across the country began holding unofficial 420 celebrations to smoke and show off their coolest bongs. However, administrations like the University of Colorado imposed fines for participating students. The press this reaction generated arguably gave the holiday an even higher profile, spreading awareness of 420 as a day of cannabis appreciation.

Legalization Leads to Bigger Blowouts

As the legalization of marijuana becomes more prevalent, 420 gatherings in major American cities have grown in size. Some of the biggest public parties include San Francisco, Washington DC, and Sacramento. In Denver, nearly 50,000 weed lovers celebrate at a free event held in front of the State Capitol.

Set in Stone

It’s not often that a group of teenagers change the world by getting high and hunting for treasure. But that’s precisely what the Waldos did. In 2017, the Oxford Dictionary officially added 420 to its much-respected catalog of English. And it cited the Waldos as the rightful creators. The origin of 420 is now official; you can even look it up in the dictionary.

Even though we’ve narrowed it down to a single origin, there is more than one way to celebrate 420. Whether you want to take this day to try a new strain or treat yourself to a new glass pipe, check out our online smoke shop for your next 420 celebration. We offer a huge range of products at affordable prices. And you can get 10% off your first order when you sign up for our email newsletter.

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