Meta, which owns Facebook, Instagram and WhatsApp, has announced that it will cut 13% of its workforce.
The first mass lay-offs in the firm's history will result in 11,000 employees, from a worldwide headcount of 87,000, losing their jobs.
Meta chief executive Mark Zuckerberg said the cuts were "the most difficult changes we've made in Meta's history". The news follows major lay-offs at Twitter, which cut about half its staff, and other tech firms.
"I know this is tough for everyone, and I'm especially sorry to those impacted," he wrote in a statement.
Mr Zuckerberg blamed massive long-term expectations for growth based on the firm's rise in revenue during the pandemic. "Many people predicted this would be a permanent acceleration," he wrote, "I did too, so I made the decision to significantly increase our investments."
Instead he said "macroeconomic downturn" and "increased competition" caused revenue to be much lower than expected
"I got this wrong, and I take responsibility for that," he said.
The announcement of job cuts was widely expected.
Mr Zuckerberg told hundreds of Meta executives of the plans on Tuesday, the Wall Street Journal reported.