Cloudflare
Also known as: CF, Cloudflare CDN, Cloudflare Workers
Cloudflare is a network services company that operates one of the world's largest content delivery networks.
When you route your website through Cloudflare, it caches your content close to visitors, blocks malicious traffic, and provides fast global DNS, often making sites faster and more secure with no code changes.
Cloudflare, explained at three levels
At home
Cloudflare works like a receptionist in front of your office. Visitors don't walk straight to your desk (your server); they reach the nearest Cloudflare location first. If it already has a copy of the page, it hands that over instantly. If a visitor looks like an attacker, it turns them away. Only legitimate requests it can't answer itself get passed through to your server.
At work
Cloudflare is a network that sits between a company's website and its visitors. Once a company points its domain's DNS at Cloudflare, every request passes through Cloudflare's servers first, where content is cached, attacks and bots are filtered, and TLS certificates are handled automatically. Businesses care because they get faster pages, lower hosting bandwidth, and protection from DDoS attacks without changing their own servers, often starting on a free plan.
At home
Cloudflare's core services stack on its role as a reverse proxy. Authoritative DNS answers lookups for your domain. The CDN caches static files at edge locations. The WAF (Web Application Firewall) inspects requests for attacks such as SQL injection and cross-site scripting, and DDoS mitigation absorbs floods. Rules products such as Redirect Rules and Transform Rules, which replaced the older Page Rules, rewrite requests, and Workers runs your own JavaScript at the edge.
At work
For teams, Cloudflare's value comes from four layers working on the same request path. Edge caching cuts latency. Security tools, including WAF rules, bot management, and rate limiting, decide what reaches the origin. Load balancing with health checks steers traffic away from failing servers. Zero Trust products such as Cloudflare Access put an identity check in front of internal apps, so staff reach them through Cloudflare instead of a traditional VPN.
At home
Cloudflare runs an anycast network: its data centres in more than 300 cities announce the same IP addresses, and BGP, the internet's routing protocol, sends each visitor to the nearest one. Every server runs every service, so any location can answer any request. That spreads a DDoS flood across the whole network instead of piling it on one origin. In my view, that design is why Cloudflare can offer DDoS protection free while others charge heavily.
At work
Cloudflare Workers run V8 isolates at the edge with ~0ms cold starts: they're not VMs or containers. Workers KV provides eventually consistent key-value storage; Durable Objects provide strongly consistent coordination. Cloudflare's WARP client and Gateway form a SASE (Secure Access Service Edge) architecture for enterprise Zero Trust networking.
Real-world examples
At home
Jerome pointed his domain's nameservers to Cloudflare. Within 24 hours, his blog loaded 40% faster for international visitors, got free SSL, and was protected from the bot traffic that used to spike his hosting bills.
At work
Nadia's team uses Cloudflare's WAF to block SQL injection attempts before they reach their origin servers, rate-limiting rules to throttle abusive API clients, and Cloudflare Access to protect their staging environment without a VPN.
Common confusions
- Cloudflare hosts your website — Cloudflare sits in front of your hosting (AWS, your own server, etc.): it doesn't replace it. Your content still needs to live somewhere; Cloudflare caches and protects it.
- Cloudflare is just a CDN — CDN is one of many products. Cloudflare also offers DNS, DDoS protection, WAF, Zero Trust access, serverless compute (Workers), email security, and AI inference at the edge.
For analysts
Cloudflare Analytics provides traffic data (requests, bandwidth, threats blocked, cache hit ratios) without JavaScript tracking, making it useful for privacy-respecting performance monitoring.
History & origin
Cloudflare launched publicly in 2010, founded by Matthew Prince, Michelle Zatlyn, and Lee Holloway. It grew rapidly by offering a free tier that gave small websites enterprise-grade DDoS protection and CDN for the first time. Notable milestones include absorbing some of the largest DDoS attacks ever recorded (above 20 Tbps by 2025), launching Workers (serverless edge computing) in 2017, and expanding into Zero Trust security and AI inference. Cloudflare's network now spans 300+ cities.