420: the history, origin and myths surrounding cannabis

In 1971, a group of five pupils at San Rafael High School in California nicknamed themselves the « Waldos » because they used to meet by one of the school's walls. Every day at 4.20 pm, once lessons were over, they set off in search of an abandoned cannabis field a friend had told them about, and never found it. The meeting, repeated week after week, turned into a private code between them: « 420 », literally the time they gathered. One member of the group had a brother close to the circle around the rock band Grateful Dead, which allowed the term to circulate on the Californian music scene in the late 1970s, well beyond the original five schoolboys.

The American magazine High Times played a decisive part in spreading the term from the early 1990s onwards, by telling the Waldos' story and presenting 20 April as an informal date for cannabis enthusiasts. The date, written 4/20 in the American format, thereby became a recognised convention in several English-speaking countries, giving rise to public gatherings, notably in Denver and Vancouver, where several thousand people meet each year on 20 April.

Beyond the annual gathering, the number 420 has established itself as a recurring nod in popular culture: clocks symbolically set to 4.20, references in films and songs, products numbered 420 in some North American shops. That ubiquity has paradoxically deepened the confusion about where the term really comes from, several competing legends having emerged over the decades to explain a figure that has become a cult reference.

Several alternative explanations circulate online, none of them verified:

• The police-code myth. An urban legend holds that 420 was a radio code used by American police to report cannabis possession. No police source confirms that origin, and the Waldos' account, documented by several American journalists, remains the most solidly established version.
• The article-of-law myth. Others mention an article 420 of the Californian penal code relating to cannabis. No article of that number exists in that form in American legislation.
• The Bob Dylan song myth. Some link 420 to the song « Rainy Day Women #12 & 35 » (12 × 35 = 420). This is a numerical coincidence popularised after the fact, with no proven link to the real origin of the term.

In France, the legal framework draws a clear line between recreational cannabis, still banned by the Public Health Code, and hemp and legal CBD, the sale of which is authorised under strict conditions (THC ≤ 0.3 %, order of 30 December 2021). 20 April is still sometimes marked in certain informal circles or on social media as a cultural symbol, without this carrying any legal weight or changing the status of the products sold in French shops. No French law mentions this number.

Is 420 an official American police code?

No. That explanation is an urban legend, unconfirmed by any American police or administrative source.

Where does the term 420 really come from?

From a daily meeting set at 4.20 pm by a group of five Californian high-school pupils, the « Waldos », in 1971, later popularised by High Times magazine.

Is 420 marked in France?

It is sometimes mentioned in cannabis culture online, but with no official recognition and no link to the French legal framework for hemp and CBD.

Does 20 April have any link with the legal CBD sold in France?

No regulatory link. CBD is governed by specific rules (THC threshold, Novel Food status) that are independent of this cultural symbol.