Meta and other tech giants want to ditch the leap second

26 Jul 2022

Image: © cosma/

An industry group says it’s time to leave the leap second in the past due to the disruptions it can cause, such as data corruption and site crashes.

Meta, along with other tech giants and two standard-setting agencies, has proposed ditching the leap second.

The leap second is a time adjustment added to Coordinated Universal Time (UTC) in order to keep atomic clocks synchronised with astronomical time. Since the introduction of the leap second in 1972, UTC has been updated 27 times.

Meta said it is supporting an industry effort to stop future introductions of leap seconds. CNET reports that this effort includes Google, Microsoft and Amazon, along with the US National Institute of Standards and Technology and the International Bureau of Weights and Measures.

Meta said introducing new leap seconds is a “risky practice that does more harm than good” and there are now new technologies available to replace this practice.

“While the leap second might have been an acceptable solution in 1972, when it made both the scientific community and the telecom industry happy, these days UTC is equally bad for both digital applications and scientists, who often choose TAI or UT1 instead,” Meta engineers said in a blogpost.

They added that some previous leap seconds caused “an unusual timestamp” that resulted in crashed computer programs or corrupted data.

In 2012, a leap second change caused Reddit to go offline and there were issues affecting Mozilla, LinkedIn, Yelp and BuzzFeed. At the start of 2017, a leap second issue at Cloudflare caused some of its customers’ servers to go offline.

Meta said the time adjustments cause issues across industries and continue to present risks. The tech company added that because it’s a rare event, it “devastates the community” every time a new second is introduced.

“With a growing demand for clock precision across all industries, the leap second is now causing more damage than good, resulting in disturbances and outages.”

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Leigh Mc Gowran is a journalist with Silicon Republic