A significant technical failure at the internet infrastructure giant Cloudflare caused widespread disruption across the web on Tuesday, 18 November 2025, taking down hundreds of popular websites.
What Happened During the Outage?
The problems began at approximately 11:30 am UK time, with users across the UK and beyond suddenly unable to access a wide array of online services. Major platforms, including the social media site X (formerly Twitter) and the music streaming service Spotify, displayed error messages indicating that their pages could not load. The film review community Letterboxd was also among the high-profile sites affected.
Cloudflare, a company that provides essential technologies to power and protect websites, quickly acknowledged the issue. The company confirmed it was actively investigating reports of "Widespread 500 errors" that were impacting a large number of its customers. The outage was so severe that it even affected Cloudflare's own customer dashboard and application programming interface (API), hindering the ability of site administrators to manage their services.
The Critical Role of Cloudflare
The scale of the disruption highlighted the critical, yet often invisible, role that companies like Cloudflare play in the modern internet's ecosystem. The firm provides services that protect websites from cyber attacks and help manage heavy traffic loads, ensuring sites remain online and performant. When such a central provider experiences problems, the effects ripple outwards, impacting seemingly unconnected websites that all rely on the same underlying infrastructure.
This incident serves as a stark reminder of the internet's interconnected nature and the potential vulnerabilities that can arise from depending on a concentrated set of core infrastructure providers.
