Aggregation & Range Conversion
Subnet Calculator — Aggregator
Aggregate a list of CIDRs into the minimal summary blocks, or convert an IP range into the smallest CIDR list. Useful for route summarization, firewall rule cleanup, and network design.
Paste any list of CIDRs. Overlapping or adjacent blocks merge into the minimal summary set.
Enter the start and end IPs of the range. They’ll be expressed as the minimum aligned CIDR blocks.
Choose a mode and enter input above to see the aggregated CIDR blocks.
One row per output CIDR block, in physical address order. Network Name auto-fills as Block 1, Block 2, etc., with a blank row between rows.
CIDR Reference
Subnet sizes and usable host counts for each CIDR.
| CIDR | Subnet Mask | Total Addresses | Usable Hosts |
|---|
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