How Cloudflare works
Cloudflare is designed for easy setup. Anyone with a website and their own domain can use Cloudflare regardless of their platform choice. Cloudflare doesn’t require additional hardware, software, or changes to your code.
Cloudflare stops malicious traffic before it reaches your origin web server. Cloudflare analyzes potential threats in visitor requests based on a number of characteristics:
- Visitor's IP address
- Resources requested
- Request payload and frequency
- Customer-defined firewall rules
A DNS lookup of a proxied (orange-clouded) Cloudflare subdomain returns . Proxied traffic comes to Cloudflare's edge and then Cloudflare forwards the request to your server. Cloudflare masks your origin IP address for proxied DNS records so attackers cannot bypass Cloudflare and directly attack your origin web server.
Visitor <--[Connection 1]--> Cloudflare Edge <--[Connection 2]--> Origin Server
A DNS lookup of an unproxied (grey-clouded) Cloudflare subdomain returns the IP address that you have entered for the record. Unproxied traffic goes directly to your origin server and does not receive any of the benefits of using Cloudflare.
Visitor <--[Connection]--> Origin Server
Cloudflare optimizes the delivery of website resources for your visitors. Cloudflare’s data centers serve your website’s and ask your origin web server for dynamic content. provides a faster route from your site visitors to our data centers than would be available to a visitor directly requesting your site. Even with Cloudflare between your website and your visitors, resource requests arrive to your visitor sooner.
Cloudflare’s globally distributed routes visitor requests to the nearest Cloudflare data center. Cloudflare distributed DNS responds to website visitors with Cloudflare IP addresses for traffic you proxy to Cloudflare. This also provides security by hiding the specific IP address of your origin web server.
Also, our flat-rate pricing structure provides predictability and reliability in your and bandwidth expenses. Cloudflare does not have bandwidth limits for domains on the Free, Pro and Business plans as long as those domains comply with our . However, your hosting provider may still impose limits on bandwidth usage and/or charge for bandwidth.
Note that additional terms may apply to:
- Self-serve domains with add-on features
- Domains in the Enterprise plan (contact your Cloudflare Account Team for additional details)