Why is the number "13" considered to be unlucky? Who determined that it should be?

Answer 1

Basically the answer to your question is unknown but here are some theories.

The number 13 has been considered unlucky for a long time, and by people all over the world. The early Romans thought 13 was a sign of death and destruction. And according to Norse mythology, if you sat 13 people down at a table, that was very unlucky. (Why? At a banquet of 12 people in Valhalla, an intruder –number 13 – caused the death of Balder’s son Odin). According to historians, there were 13 people at Christ's Last Supper and Christ was crucified on Friday 13th. So, Friday 13th is considered as Unlucky.

According to another interpretation, the number 13 is unlucky because it is the number of full moons in a year. Women living in a natural environment tend to have their period during a full moon. A woman typically has 13 periods in a year. In the past, a woman who "bled" during a full moon was seen as a witch. The fear of women's connection to the moon, as well as the association of the full moon with mental disorders has, according to this theory, caused the number to be seen as bad luck, and connected to supernatural forces.

The number is also considered unlucky by some as it is the sum of 1+4+5+3, the year of the fall of Constantinople to the Turks, marking the end of the Byzantine Empire, though it may be considered lucky by Turks on the same basis.

Amongst some Chinese people, it is regarded as a lucky number because it sounds similar to "實生", which means "must be alive". But this belief is not universal, or even known to all Chinese. Also, 13 is regarded as unlucky by those Chinese under the influence of foreign cultures.

In the Persian culture, 13 is also considered an unlucky number. On the 13th day of the Persian new year (Norouz), people consider staying at home unlucky, and go outside for a picnic in order to ward off the bad luck.

Modern-day witches have reclaimed the number 13 as a lucky and significant number. This may be similar to witches reclaiming other previously negative terms and ideas associated with witchcraft, such as black cats, brooms, and even the term witch itself.

In the Sikh religion, the number 13 is considered a special number since 13 is tera in Punjabi, which also means "yours" (as in, "I am yours, O Lord"). When Guru Nanak Dev Ji had a job of counting stocks of items, he counted from 1 to 13 (in Punjabi) as one does normally, but after reaching the count of 13, he would just repeat "tera", since all items were in fact God's, as God created them. When somebody heard this while passing, Guru Nanak Dev Ji was confronted about this, and his records were checked. It was a miracle since they were all perfect, yet he never seemed to count the items properly.
In The Hitchhiker's Guide to the Galaxy, "What is six times nine" is posed as the question to the answer to life, the universe and everything (42). This is true in base 13, although this was merely coincidence according to author Douglas Adams. Similarly, the fact that the official numbering system for counties of Norway skips over "county number 13" is due not to superstition but historical accident.

In Asian cultures, the numbers '4' and '9' are often considered unlucky due to their resemblance to the words for 'death' and 'suffering'. But if these numbers are added together, they equal the traditionally unlucky number of the West, '13'.



The fear of the number 13 is called triskaidekaphobia. Many hotels have no room 13, and many buildings have no 13th floor. Next time you fly, see if there is a row 13 in the plane. As date, 13 isn’t too lucky either, especially when it falls on Friday. That was always thought of as a really bad day to start a new project or to begin a ship voyage. Movers, doctors and dentists say their business drops on Friday the 13th. The good news is that a maximum of three Friday the 13th can occur in a year, and sometimes there is just one.

Answer 2

Originally, it comes from the fact that there were 13 people attending 'The Last Supper'.
For many years it was considered unlucky to serve 13 at a table. From there, the 'unlucky' superstition was extended to all things numbering 13.

Answer 3

Why 13 is famous as Unlucky?
Alexander wanted to be a God and accordingly made a 13th statue on the place of his capital. He died and people considered that his will to be a 13th God (12 gods, one for each month were known) was the reason of his death. After that this number was considered as unlucky.
According to historians, there were 13 people at Christ's Last Supper and Christ was crucified on Friday 13th. So, Friday 13th is considered as Unlucky.

Answer 4

It's an extension of the Friday the 13th superstition. Friday the 13th is considered unlucky because of Friday October, 13, 1307 AD. On this day, King Philip IV of France had nearly all of the members of the powerful Knights Templar group assasinated or arrested simultaneously all around Europe. Such a remarkably incisive strike required careful planning, and very good luck to pull off. Or very, very, bad luck if you were a Templar knight.

Answer 5

I know 12 is a holy number, the 12 disciples of Christ, 12 makes a dozen, 12 hours on the clock, but I don't know why the next number up, 13, is considered unlucky. But who would have put 13 hours on the clock? I don't like baker's dozens for instance. It's a doughnut too much. It's uneven, odd, wierd.

Answer 6

The fall of the Knights Templars, Friday the 13th 1307. They had a special about it that aired the last Friday 13th.

" in 1307 the impoverished Philip IV, king of France, with the aid of Pope Clement V, arranged for the arrest of the French grand master Jacques de Molay (1243?–1314) on charges of sacrilege and Satanism. Molay and the leading officers of the order confessed under torture, and all of them were eventually burned at the stake. The order was suppressed in 1312 by Clement V and its property assigned to the rival Knights Hospitalers, although most of it was in fact seized by Philip and by King Edward II, who disbanded the order in England."

Answer 7

Its actually a cultural phonomenan because it shows up in multiple cultures as bad luck. It may be that the Christians drew a parallel from the 13 witches in Scandanavian culture and Judas being the 13th apostle. The Judas thing is the main one any more though.

Answer 8

Some unlucky fool.

Answer 9

I hit my biggest ever gambling winning (on roulette) with number 13. A bakers dozen is 13, that's like one free, which is good luck. I was 13 years old once, as I entered my "teen years" it was the first step. We all were (okay, most of us) once.

Answer 10

It is based on the pagan ritual of observing the 13 lunar cycles. Anything pagan was considered sinister and the work of the devil by Christians.