Large parts of the web are down for thousands of people, with social media websites like X, formerly called Twitter, not loading.
Issues with the platforms, which also include PayPal and ChatGPT, began at around 11.20am.
League of Legends, one of the world’s most popular video games, was also not working.
Several of the platforms have their servers hosted on Cloudflare, which provides tools to protect them from cyberattacks and allows sites to load content more quickly amid heavy traffic.
It also acts as a domain name server – a directory for websites and a tool tied to mass outages in recent months.
More than 11,000 people were reporting issues with Cloudflare at 11.40am, according to outage tracker Downdetector.
Accessing some websites now sees users greeted by the Cloudflare error code 500, which points to issues with the server or the website’s code.
Cloudflare says on its status page that engineers are investigating the issue ‘which potentially impacts multiple customers’.
It said at 12.20pm: ‘We are seeing services recover, but customers may continue to observe higher-than-normal error rates as we continue remediation efforts.’
OpenAI, the start-up behind ChatGPT, confirmed that the chatbot is down for some users and is investigating.
Meta, which owns Facebook, however, is reporting no issues.
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