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CIDR aggregator

Combine overlapping and adjacent IPv4 CIDRs without adding addresses to the result.

Exact CIDR consolidation
4input CIDRs
1output CIDRs
Unique addresses512
Extra addresses0
Continuous ranges1
Entries with host bits cleared0
192.168.0.0/23192.168.0.0 → 192.168.1.255512 addresses · /23

Adjacent blocks merge only when the resulting CIDR has exact coverage. Separate ranges retain the gaps between them.

One CIDR per line. Up to 1,024 entries; blank lines are ignored.

Combining address sets cannot preserve ordered firewall rule behavior. Use one policy per list.

Processed on your device

How it works & useful details

How it works & limits

Combine IPv4 CIDRs into their smallest exact cover. Duplicate, contained, overlapping and adjacent blocks are merged where alignment permits. Gaps remain gaps: the result never adds addresses that were not in the input.

Enter one CIDR per line, up to 1,024 entries and 64,000 characters. Host bits are cleared before combining. Saved text has one normalized CIDR per line. This tool does not preserve rule order or separate allow/deny policies; combine only entries with the same intended meaning.

Your working space

Explore the live view, then save copyable text and a downloadable file. Everything is calculated locally. Inputs are not stored; refreshing clears them.

These tools inspect address notation and ranges. They do not contact addresses, check availability or establish connectivity.