IP/CIDR Overlap Checker
Check whether IP ranges and CIDR blocks overlap, contain each other, or conflict
Add Ranges
Accepts CIDR notation (10.0.0.0/8), single IPs (treated as /32 or /128), and comma-separated entries.
About IP/CIDR Overlap Checking
CIDR (Classless Inter-Domain Routing) notation defines IP address ranges using a network prefix and mask length. When planning network infrastructure, VPC peering, firewall rules, or routing tables, overlapping ranges cause conflicts that can lead to unreachable hosts or misrouted traffic.
This tool detects three types of relationships: exact duplicates (identical ranges), containment (one range fully contains another), and partial overlaps (ranges share some but not all addresses). It supports both IPv4 and IPv6 CIDR notation.