Friday the 13th
Friday the 13th is considered an unlucky day in Western superstition. It occurs when the 13th day of the month in the Gregorian calendar falls on a Friday, which happens at least once every year but can occur up to three times in the same year. For example, 2015 had a Friday the 13th in February, March, and November, which will happen again in 2026; 2017 through 2020 had two Friday the 13ths, as did 2023; 2016, 2021 and 2022 had just one Friday the 13th, as will 2025; 2024 will have two Friday the 13ths.[1]
This article is about the superstition. For the horror film franchise, see Friday the 13th (franchise). For other uses, see Friday the 13th (disambiguation).A month has a Friday the 13th if and only if it begins on a Sunday.
Occurrence
Distribution
Each 400 year Gregorian solar cycle contains 146,097 days (with 97 leap days) or exactly 20,871 weeks. Each cycle contains the same pattern of days of the week and therefore the same pattern of Fridays that are on the 13th. The 13th day of the month is very slightly more likely to be a Friday than any other day of the week.[31][32][33]