Friday the 13th: Why does this date scare so many people? Discover 13 mysteries and curiosities

Friday the 13th has arrived again and, for many people, it is better not to risk it! This Friday, the 13th, the calendar brings together two things that for centuries have aroused fear and curiosity: the number 13 and Friday. But does this combination really bring bad luck? Where did this belief come from? And why are black cats, broken mirrors, and stairs involved in this story?

The date is surrounded by legends, historical events, religious traditions and chilling stories. Although there is no scientific evidence that Friday the 13th is naturally more dangerous, superstition remains alive in different countries, including Brazil.

And 2026 has a peculiarity: this is the third and last Friday the 13th of the year. The others took place on February 13 and March 13. The next meeting between the day of the week and the dreaded number will only be on August 13, 2027.

Why is Friday the 13th considered a bad day?

The most well-known explanation is linked to the Christian tradition. During the Last Supper, Jesus Christ met with the 12 apostles, forming a group of 13 people. Among them was Judas Iscariot, responsible for the betrayal of Jesus, according to biblical accounts.

Friday, in turn, is traditionally associated with the crucifixion of Christ. As the centuries passed, these two references became related to the idea of suffering, betrayal and bad luck.

Another interpretation involves the symbolism of numbers. While 12 appears in different traditions as a representation of a complete cycle—12 months of the year, 12 zodiac signs, and 12 hours on the traditional watch dial—13 would be a break from that harmony.

However, researchers point out that there is no single proven origin for superstition. The fame of the date probably resulted from the combination of beliefs that were strengthening over time.

The mystery of the Knights Templar: a tragedy in the middle of Friday the 13th

One of the most impressive stories involving the date occurred on October 13, 1307, also a Friday.

At the time, King Philip IV of France ordered a major operation against the Knights Templar, a powerful military and religious order that arose during the Crusades.

Members of the order were arrested and charged with heresy. Many have suffered persecution, interrogation and torture. The process ended with the dissolution of the order, and some of its members were subsequently executed.

The story feeds into mysterious theories and narratives involving the Templars.

Despite this, there is an important detail: historians point out that there is no evidence that the superstition of Friday the 13th arose precisely because of these arrests. The link gained popularity mainly through later interpretations, including works of fiction.

13 Curiosities About Friday the 13th You May Not Know

1. Black cat does not give bad luck — but suffers from superstition

The association of black cats with witchcraft has spread over different historical periods. Belief has no scientific basis and can contribute to prejudice and mistreatment of animals.

2. In Italy, the feared number is 17.

In part of Italian culture, Friday the 17th is considered unlucky. One explanation is in the number XVII, which can be reorganized to form VIXI, a Latin expression associated with the idea of a life that ended.

3. In Spain, Tuesday the 13th is what worries

The superstition changes according to the country. In many Spanish-speaking regions, Tuesday the 13th is known to bring misfortunes.

4. The fear of the number 13 has a name

Triscaidekaphobia is the name given to the intense fear of the number 13. Parascedecatriaphobia refers specifically to the fear of Friday the 13th.

5. Some buildings avoid the 13th floor

In certain hotels and buildings, especially where superstition is popular, the numbering can go directly from the 12th to the 14th floor. The floor still exists, but it gets another number.

6. A 1907 soap opera helped spread the fame of the date

The writer Thomas W. Lawson published Friday, the Thirteenth, a story about a broker who uses superstition to provoke panic in the financial market.

7. Cinema has turned the date into a synonym for horror

Released in 1980, the film Friday the 13th kicked off one of the best-known franchises in the genre. Jason Voorhees became the big icon of the series, although he is not the central killer of the first film.

8. Breaking a mirror doesn’t mean seven years of bad luck

Belief is often related to ancient conceptions of the reflection and renewal of life. There is no evidence that a broken mirror determines future events.

9. Walking under a ladder has a real danger

Although it is associated with bad luck, the real risk is physical: a tool or object may fall, or the ladder may lose stability.

10. In Norse mythology, Loki appears in a story about 13 guests.

A popular narrative describes Loki as the 13th participant in a banquet that ends in tragedy. It is one of the folkloric explanations linked to the fear of the number, but not a historically demonstrated origin.

11. In Japan, the number 4 also arouses fear

One of the Japanese pronunciations of the number 4, shi, sounds like the word for death. Therefore, some people avoid the number in certain situations.

12. Every year there is at least one Friday the 13th.

According to the Gregorian calendar, any year will have at least one and at most three Fridays. In 2026, there are three; in 2027, there will be only one.

13. Science does not prove that the day is cursed

Studies have already investigated accidents and other risks associated with the date, with varying results. There is no consistent demonstration that the number itself or the day of the week causes bad luck.

What does science say about bad luck on Friday the 13th?

Psychology offers an interesting explanation for the permanence of these beliefs: when someone expects something bad to happen, they can pay much more attention to negative events.

If a person loses the keys on Friday the 13th, for example, they can associate the problem with the date. If the same situation happens on any other Friday, it will probably be considered just a setback.

This behavior is related to the so-called confirmation bias, which leads people to value information that reinforces existing beliefs.

A scientific research published in 2026, based on more than 43,000 arthroplasty procedures, found no significant increase in mortality or complications in surgeries performed on dates associated with superstition, including Friday the 13th.

Fear, however, can be real. For some people, date anxiety influences decisions, habits, and behaviors.

Is Friday the 13th a bad day or just a superstition?

For those who believe in signs, energies and popular traditions, Friday the 13th will continue to be a date of special care. For those who prefer historical and scientific explanations, it is a cultural phenomenon that has spanned generations.

In Ponta Grossa, in Campos Gerais and in the rest of Brazil, the day can be an opportunity to get to know stories, watch suspense movies or simply play with superstitions.

The fact is that Friday the 13th continues to arouse curiosity more than seven centuries after the events involving the Templars.

What about you? Are you one of those who avoids going under stairs, gets suspicious when you see a black cat, or believe that it’s just a coincidence?

One thing is for sure: the fear of Friday the 13th has already become part of the story. The bad luck, for now, remains unproven.