Cloudflare source IPs are the IP addresses used by Cloudflare services (such as Load Balancing, Gateway, and Browser Isolation) when sending traffic to your private networks. For customers using legacy mode routing, traffic to private networks is sourced from public Cloudflare IPs, which may cause IP conflicts. For customers using Unified Routing mode (beta), traffic to private networks is sourced from dedicated, non-Internet-routable private IPv4 range to ensure:
Symmetric routing over private network connections Proper firewall state preservation Private traffic stays on secure paths
Key details:
IPv4: Sourced from 100.64.0.0/12 by default, configurable to any /12 CIDR IPv6: Sourced from 2606:4700:cf1:5000::/64 (not configurable) Affected connectors: GRE, IPsec, CNI, WARP Connector, and WARP Client (Cloudflare Tunnel is not affected)
Configuring Cloudflare source IPs requires Unified Routing (beta) and the Cloudflare One Networks Write permission. For configuration details, refer to Configure Cloudflare source IPs.
Fetched April 4, 2026