Programmer's Day
World Programmer's Day
From Wikipedia, the free encyclopedia
Programmer's Day, also known as the Day of the Programmer and occasionally as Day 2^8, is an international professional day that is celebrated on the 256th (hexadecimal 100th, or the 28th) day of each year. This is September 13 in common years and September 12 in leap years.
| Programmer's Day | |
|---|---|
| Observed by | Worldwide |
| Type | International |
| Date | 256th (hexadecimal 100th, or the 28th) day of each year (September 13 in common years, and September 12 in leap years) in Russia |
| 2025 date | 2025-09-13 |
| Duration | "1 day" |
| Frequency | Annual |
| First time | 2009 |
| Related to | Engineer's Day |
The number 256 (28) was chosen because it is the number of distinct values that can be represented with a byte, a value well known to programmers. 256 is also the highest power of two that is less than 365 and 366, the number of days in a common year and leap year respectively.
History
As early as 2002, this particular day was proposed by Valentin Balt and Michael Cherviakov (aka htonus), employees of Parallel Technologies (a software company), who tried to gather signatures for a petition to the government of Russia to recognize the day as the official Day of the Programmer.[1]
On July 24, 2009, the Ministry of Communications and Mass Media of Russia issued a draft of an executive order on a new public holiday, the Day of the Programmer.[2][3] On September 11, Russian president Dmitry Medvedev signed the decree.[4][5]
Variations
Chinese Programmer's Day
In China, the programmer's day is October 24,[6] which has been established for many years.[7]
The date was chosen because it can also be written as 1024, which is equal to 210 and corresponds to the kibi (Ki) binary prefix. It is also a consistent date regardless of leap years.[citation needed]
Ukrainian Programmer's Day
In Ukraine, the day was observed on both January 7 (as International Programmer's Day, founded in 2007) and the 256th-day September date. In 2022, the country's IT community ceased observing the September date, as it was of Russian origin. In 2025, the Government of Ukraine formally recognised programmer's day as January 7.[8]
