Anthropic’s Claude AI chatbot is down as company confirms ‘elevated error rates’ for Opus 4.5 and Sonnet 4.5
Users of Anthropic's Sonnet 4.5 and Opus 4.5 models are being met with "elevated error rates"
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Anthropic’s Claude AI is down, with users reporting issues accessing the popular chatbot.
Reports of an outage have been circulating social media since around 9am (UK time) today, with many encountering errors while using it and others unable to access the tool entirely.
According to figures from Downdetector, there have been more than 1,500 separate reports highlighting issues with the platform.
Anthropic has confirmed the issue, advising users that they may encounter “elevated error rates” on Sonnet 4.5 and Opus 4.5, two of the company’s leading AI models.
Opus 4.5 was launched in November last year, and primarily used in coding activities by software developers.
Exact details on the cause of the outage are yet to be determined. However, in a status update, Anthropic said the issue had been “identified and a fix is being implemented”.
That update, issued at 9.16am (UK time), has since been followed up by three separate updates insisting the company is “continuing to work on a fix for this issue”, suggesting continued difficulties for the firm.
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ITPro has verified the issues, having first encountered issues accessing the service before being met with a message warning responses are “taking longer than usual”.
UPDATE: Anthropic had announced a fix has been implemented and will continue "monitoring the results".
Statistics from Downdetector now show a marked dip in outage reports.
This is a developing story and ITPro will update as new information becomes available.
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Ross Kelly is ITPro's News & Analysis Editor, responsible for leading the brand's news output and in-depth reporting on the latest stories from across the business technology landscape. Ross was previously a Staff Writer, during which time he developed a keen interest in cyber security, business leadership, and emerging technologies.
He graduated from Edinburgh Napier University in 2016 with a BA (Hons) in Journalism, and joined ITPro in 2022 after four years working in technology conference research.
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