Millions of internet users across the United Kingdom faced significant disruption on Thursday morning due to a major outage at the web infrastructure giant Cloudflare. The incident caused problems accessing a host of popular websites and services, highlighting the company's critical yet largely invisible role in the modern internet.
What Happened During the Cloudflare Outage?
According to data from the outage monitoring website Downdetector, reports of problems surged dramatically from almost normal levels before 8am to 1,688 incidents by 9am on December 5, 2025. Users attempting to access various online platforms were met with error messages, including the '500 internal server error'.
The disruption marks the second significant outage in a short period, following a similar widespread incident reported by the Mirror on November 18. On social media platform X, frustration was palpable. User Kisan Tamang posted, "Cloudflare outage again?!", while Alex Bilbie commented, "I really like Cloudflare but two outages in a month is starting to look sloppy."
Understanding Cloudflare's Crucial Role
Despite its low public profile, Cloudflare is a backbone of the internet. It operates as a content delivery network (CDN) and distributed DNS (domain name system) provider. Its services are vital for protecting websites from malicious attacks like DDoS (distributed denial of service) and optimising their performance for end-users.
Cloudflare's own data states it helps manage approximately 19.4% of all websites globally. This means when its systems experience issues, the ripple effect is immense. The company hosts websites on its own servers, providing enhanced security and faster load times for a vast array of online businesses.
Major Services and Websites Impacted
The outage demonstrated Cloudflare's extensive reach, with numerous high-profile platforms experiencing problems. Key firms that rely on Cloudflare's services include:
- X (formerly Twitter)
- Mozilla Firefox
- Discord
- Shopify
- Uber
- Open AI (ChatGPT)
- Fiverr
At the time of the disruption, Cloudflare had not posted an official statement on its website or its X account regarding the cause of the outage. The incident serves as a stark reminder of the internet's reliance on a concentrated set of infrastructure providers. For many UK users, the morning of December 5 was a lesson in how a single point of failure at a company like Cloudflare can disrupt digital life on a national scale.
