Year 2038 problem

Animation showing how the date would reset, represented as a signed 32-bit integer (at 03:14:08 UTC on 19 January 2038).

The Year 2038 problem could affect computers that store time as the number of seconds since 1 January 1970 at 00:00:00 UTC, using a 32-bit signed integer.

The biggest number you can store this way is 2,147,483,647 seconds after 1 January 1970. This means 19 January 2038 at 03:14:07 UTC. The problem begins one second after this time. The computer will add 1 to this 32-bit number, and the computer will set the value to negative 2,147,483,648 seconds. This means 13 December 1901 at 20:45:52 UTC. Depending on how the computer has been programmed, the computer could behave incorrectly or even stop running.

A solution to this problem is to store the time in a 64-bit value, which will work for 292 billion years. Many computers already store the time in a 64-bit number. Computers that store time in a 32-bit number will need to be reprogrammed before 2038.

Further reading

• ""Y2K" Fictionalizes The Past Cyber Threat—But More Are Coming," ''Science Friday',' https://www.sciencefriday.com/articles/y2k-fictionalizes-the-past-cyber-threat-but-more-are-coming/
• Countdown clock: https://38bug.com/