A Clock Ticking Toward 1901
At exactly 03:14:08 UTC on 19 January 2038, some computers will attempt to take one small step forward in time—and leap 136 years backward instead. This is the Year 2038 problem, caused by the overflow of signed 32-bit integers used to store Unix time.
Unix time counts seconds from 00:00:00 UTC on 1 January 1970. But with 32-bit signed storage, the maximum value is 2,147,483,647 seconds, ending at 03:14:07 UTC on that day. Adding one more second causes the value to wrap around to −2,147,483,648, which translates to 20:45:52 UTC on 13 December 1901.
Systems at Risk
The error affects systems using signed 32-bit integers for timekeeping—especially file systems, databases, and embedded devices. These are often designed for long life spans and may not be regularly updated. Devices from cars to routers could encounter miscalculations, crashes, or failed boot processes.
Android devices using 32-bit code have already shown susceptibility when manually set to post-2038 dates. The problem doesn’t impact systems that track only relative time or intervals without referencing absolute timestamps.
Real Failures, Real Fixes
The bug has already surfaced. In 2006, AOLserver encountered an early failure due to a configuration assigning a billion-second timeout. As that date approached, timeout math failed, causing crashes. Fixes for the broader issue vary.
Replacing 32-bit time_t with 64-bit signed integers is a common approach—extending time tracking for roughly 292 billion years. NetBSD, OpenBSD, and newer Linux kernels now use 64-bit time_t on both 32-bit and 64-bit hardware. GNU C Library, MySQL, and MariaDB have also introduced 64-bit timestamp handling on compatible platforms.
Beyond 2038
File systems like ext4 and XFS have implemented extended timestamp formats. Programming environments like Java and JavaScript already store time in milliseconds as 64-bit integers, supporting ranges millions of years wide.
In Windows, time has been stored in 64-bit 100-nanosecond units since 1 January 1601, with no risk of overflow until the year 30,828. Though not all systems are vulnerable, those that are may face critical issues unless they’re upgraded or replaced. As 2038 approaches, ongoing updates and architecture transitions aim to avert widespread disruptions.
On 19 January 2038 at exactly 03:14:08 UTC, some computers will try to move one second forward—and jump back to 1901.
This is the Year 2038 problem, a bug in systems using 32-bit signed integers to track Unix time. If left unfixed, it can break software and devices worldwide… pic.twitter.com/eruoWSGi5O
— Detective Tiger's Stories (@TigerDetective) May 28, 2025