At 4:20 p.m. every April 20, people around the world celebrate a number that started as an inside joke between five California teenagers.
420 is cannabis slang that traces back to a group of San Rafael High School students known as the Waldos, who began using the term in 1971. What started as a meeting time eventually spread through the Grateful Dead community, High Times magazine, and cannabis culture around the world.
The strange part is that they weren't trying to start a movement.
They were looking for a secret patch of weed.
Key Takeaways
- 420 originated in 1971 with five students at San Rafael High School in Northern California.
- The Waldos originally met at 4:20 p.m. near a statue of Louis Pasteur to search for a rumored abandoned cannabis crop.
- Their original code was “420 Louie,” later shortened to simply “420.”
- Connections to the Grateful Dead helped spread the term beyond their circle.
- A 1990 Deadhead flyer and subsequent coverage by High Times helped transform 420 from slang into the April 20 cannabis tradition recognized today.
- The police-code and Bob Dylan explanations are myths.
What Does 420 Mean?
420 is shorthand for cannabis and cannabis culture.
People use it in several ways. 4:20 can refer to the time of day associated with cannabis. 4/20 refers to April 20, which has become cannabis culture's unofficial annual holiday.
But the date came later.
The story actually begins with the time.
Where Did 420 Come From?
The best-documented origin of 420 goes back to five high school friends in San Rafael, California, in 1971.
The group called themselves the Waldos, reportedly because they often hung out near a wall outside San Rafael High School.
Then they heard about something considerably more interesting.
According to the story, someone connected to a U.S. Coast Guard member gave them a map supposedly leading to an abandoned cannabis crop near Point Reyes.
The Waldos decided to search for it.
Because school and sports were finished by then, they arranged to meet at 4:20 p.m. at the Louis Pasteur statue outside their school before heading out on their search.
Their reminder to each other became:
“420 Louie.”
Eventually, they dropped the "Louie."
Just 420 remained.
And despite repeated searches, they apparently never found the legendary cannabis patch.
The code proved much easier to find.
How Do We Know the Waldos Story Is Real?
The Waldos have documentation dating back to the 1970s that uses the term 420.
They saved letters and other memorabilia containing references to the number, providing unusually good historical evidence for something that began as teenage slang.
When the Oxford English Dictionary added this meaning of "420" in 2017, it cited documents connected to the Waldos among the earliest recorded uses.
That is why their story is generally regarded as the strongest documented explanation for the origin of 420.
How Did 420 Spread Through the Grateful Dead Community?
Connections between the Waldos and the Grateful Dead helped carry 420 beyond San Rafael.
One of the Waldos had a brother who was friends with Grateful Dead bassist Phil Lesh. Members of the group began spending time around the band's circle, where the slang gradually spread.
That connection turned out to be important.
The Dead didn't invent 420.
But the massive community surrounding the band gave the term somewhere to travel.
By the end of the 1980s, it was no longer just five friends speaking in code.
How Did 4/20 Become a Cannabis Holiday?
The transformation of 420 from a time of day into April 20 as a cannabis holiday appears to have accelerated around 1990.
At a Grateful Dead show, High Times reporter Steve Bloom received a flyer inviting people to gather at 4:20 p.m. on 4/20for a cannabis gathering in Marin County.
High Times published the flyer in the early 1990s and continued using 420.
That exposure helped carry the term throughout cannabis culture.
Interestingly, the people who created the original flyer that helped establish April 20 as the date remain unknown.
So there are really two origin stories:
The Waldos created 420.
The wider cannabis community turned 4/20 into a holiday.
The Biggest 420 Myths
A secret cannabis code was practically destined to attract mythology.
Is 420 a Police Code for Marijuana?
No. The police-code explanation is one of the oldest 420 myths.
There is no credible evidence that the term originated as police shorthand for marijuana use. The documented Waldos history points to their 4:20 meeting time instead.
Did 420 Come From Bob Dylan?
No.
One popular theory connects 420 with Bob Dylan's Rainy Day Women #12 & 35 because 12 × 35 = 420 and the song contains the famous refrain about getting stoned.
Great coincidence.
Not the origin.
Is 420 Connected to Hitler's Birthday?
April 20 was Adolf Hitler's birthday, but there is no evidence that this coincidence has anything to do with cannabis culture adopting 420.
The Waldos story traces the number to a time of day, not a historical birthday.
Did the Grateful Dead Invent 420?
No.
The Waldos were already using 420 before its spread through the Grateful Dead community.
The Dead connection helped popularize the term. It didn't create it.
What Does 420 Mean Today?
420 has evolved from secret slang into one of the most recognizable symbols of cannabis culture.
April 20 now includes everything from informal gatherings and festivals to legalization advocacy and major cannabis-industry events.
That evolution is pretty remarkable.
In 1971, saying "420" allowed a group of teenagers to talk about cannabis without teachers or parents knowing what they meant.
Today, you can see the same number on clothing, advertisements, product launches and events around the world.
The code isn't secret anymore.
But it survived.
What Does 420 Mean at CBDX?
For us, 420 is less about treating cannabis like a novelty and more about enjoying cannabinoids intentionally.
The cannabis world has changed dramatically since somebody handed five teenagers a treasure map in 1971.
Today's consumer can choose between THC, CBD, CBG, CBN, different strengths, different cannabinoid combinations, and even THC-free options.
At CBDX.com, that's the part of modern cannabis culture we find most interesting: having choices and knowing what you're taking.
The mystery cannabis patch may never have been found.
The precisely dosed gummy came later.
Frequently Asked Questions About 420
Why is 420 associated with weed?
420 became associated with cannabis after five California high school students known as the Waldos began using it as a private code in 1971. Their slang later spread through the Grateful Dead community and High Times.
Why do people celebrate 420 on April 20?
The original 420 referred to 4:20 p.m., not April 20. The association with 4/20 as a date developed later as the term spread through cannabis culture, particularly after a 1990 flyer promoted a cannabis gathering at 4:20 p.m. on April 20.
Who were the Waldos?
The Waldos were five friends who attended San Rafael High School in Marin County, California. They began using "420" in 1971 while searching for a rumored abandoned cannabis crop near Point Reyes.
Is 420 a police code?
No. The evidence supporting the Waldos origin is much stronger, and the police-code explanation is considered an urban legend.
Did the Waldos ever find the cannabis crop?
Apparently not.
They searched for the rumored patch repeatedly but never located it.
From Five Friends to a Worldwide Code
Five teenagers picked a meeting time.
The crop they were looking for disappeared into history.
The meeting time didn't.
More than five decades later, 420 has become universal shorthand for cannabis culture and April 20 has become its unofficial holiday.
Not because of a police code. Not because of Bob Dylan. And not because anyone sat down and decided cannabis needed its own holiday.
It began with a map, a statue, five friends and one very specific time after school.
4:20 p.m.
