What does the CIDR aggregator do?

It merges a list of individual IP addresses, IP ranges (start–end) and subnets into the smallest possible set of CIDR blocks (supernetting). Overlapping and adjacent networks are combined.

Does it support IPv4 and IPv6?

Yes. IPv4 and IPv6 are processed separately and each returned as its own CIDR list.

Is my data transmitted?

No. The calculation runs entirely in your browser – no input is sent to the server.

What is it useful for?

Mainly for compact firewall rules, routing tables and ACLs: instead of many individual networks you enter a few aggregated CIDR blocks.

CIDR Aggregator – Summarize IPs & Subnets (Supernetting)

Input

One entry per line – allowed are IP (8.8.8.8), CIDR (192.168.0.0/24) and range (10.0.0.1 - 10.0.0.20). IPv4 and IPv6 may be mixed.

My IP Subnet Calc CIDR Aggregator IP Converter IP Lookup

What is CIDR aggregation (supernetting)?

CIDR aggregation – also called supernetting or route summarization – combines several adjacent or overlapping IP networks into as few larger CIDR blocks as possible. For example 192.168.0.0/24 and 192.168.1.0/24 become 192.168.0.0/23.

This saves entries in firewall rules, routing tables and access-control lists and keeps configurations clean. The aggregator merges overlapping and directly adjacent ranges and then computes the minimal set of CIDR blocks that covers exactly the same address space – separately for IPv4 and IPv6. The entire calculation runs in your browser; no data is transmitted.