Claude AI down globally, thousands of users report authentication error

Anthropic's Claude AI suffered a widespread outage on Sunday evening, with thousands of users across the United States reporting an 'authentication service unavailable' error when trying to access the chatbot. Downdetector recorded over 15,000 error reports by 6:15 p.m. EDT.

Anthropic's status page initially confirmed an investigation into the issue affecting claude.ai, platform.claude.com, the Claude API, Claude Code, and Claude Cowork. A later update said a fix had been deployed and was being monitored. The company's status page later confirmed the issue had been resolved, but Anthropic has not disclosed the cause of the outage.

Users took to social media to report the disruption, with one in Silicon Valley noting the outage had lasted at least 15 minutes. Another remarked that the timing on a Sunday evening meant fewer workday disruptions. Downdetector showed the highest concentration of reports in major US tech hubs.