Advanced IP Supernet Calculator | IPv4 Route Aggregation Tool

IP Supernet Calculator Form

Enter at least two IPv4 CIDR blocks. This page summarizes them into the smallest possible supernet that covers every listed network.

IPv4 CIDR blocks

Use one CIDR per line. Commas and semicolons are also accepted.

Validation options

Require aligned network addresses

Remove duplicate networks

Sort networks before display

Show binary prefix analysis

Quick actions

Use the sample button to load contiguous classroom-style examples, then submit to see the summarized route above the form.

Sample use cases include route aggregation, ACL planning, address block summarization, lab exercises, and WAN routing cleanup.

Example Data Table

Input Networks	Summarized Result	Coverage Note
192.168.0.0/24, 192.168.1.0/24	192.168.0.0/23	Exact aggregation with no gaps
10.0.0.0/24, 10.0.1.0/24, 10.0.2.0/24, 10.0.3.0/24	10.0.0.0/22	Four equal blocks collapse into one route
172.16.0.0/24, 172.16.2.0/24	172.16.0.0/22	Supernet contains unused address space between inputs

Formula Used

The calculator finds the smallest supernet by comparing the lowest network address and the highest broadcast address across all valid input blocks.

1. Network address: Network = IP AND subnet mask

2. Broadcast address: Broadcast = Network OR wildcard mask

3. Supernet prefix: Count the common leading bits shared by the lowest network and highest broadcast boundaries.

4. Supernet network: Supernet network = Lowest boundary AND supernet mask

5. Supernet size: Total addresses = 2^(32 − supernet prefix)

6. Coverage: Coverage % = (Union of input addresses ÷ Supernet addresses) × 100

7. Route reduction: Reduced routes = Number of input blocks − 1

How to Use This Calculator

Enter at least two IPv4 CIDR blocks, one per line.
Enable strict alignment when every entry must already be a valid network address.
Enable duplicate removal when repeated routes should count only once.
Enable sorting for cleaner review in the results table.
Click Calculate Supernet to show the result above the form.
Review the summary cards, detailed range table, and Plotly graph.
Export the outcome using the CSV or PDF buttons.
Check the coverage and exact aggregation fields before using the summary in production routing.

FAQs

1. What does an IP supernet calculator do?

It combines multiple IPv4 CIDR blocks into the smallest summarized route that still covers every listed network. This helps reduce routing table entries and simplifies address planning.

2. Does this calculator support IPv6?

No. This version is focused on IPv4 supernetting only. It validates dotted-decimal IPv4 addresses with CIDR prefixes from /0 through /32.

3. Why can a supernet include unused space?

A summary route is based on common leading bits, not exact occupancy. When input ranges are not fully contiguous, the smallest supernet may still cover gaps between them.

4. What is exact aggregation?

Exact aggregation means the summarized supernet is filled completely by the union of your input networks, with no gaps left inside the final address range.

5. Why would strict alignment reject an entry?

Strict alignment rejects entries where host bits are set. For example, 192.168.1.5/24 is not a proper network address for that prefix, so it must be normalized or corrected.

6. How is route reduction calculated?

It is the difference between the retained input block count and one summarized route. If four blocks become one supernet, the route reduction equals three.

7. Are overlapping blocks allowed?

Yes. The calculator can process overlapping ranges and reports overlap addresses separately. This helps you spot duplicated or nested routing information before deployment.

8. When is supernetting most useful?

It is useful during route summarization, WAN design, MPLS planning, ACL optimization, BGP table cleanup, classroom subnetting practice, and documentation of grouped address pools.