CIDR Aggregation Calculator
Merge IPv4 CIDR address ranges into an exact minimal prefix cover and separately show the extra addresses in a single covering supernet.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Normalize input prefixes, merge overlapping or adjacent integer intervals and decompose each interval into aligned power-of-two blocks.
Exact union=merged intervals covered by largest aligned CIDR blocks without added addresses
Worked example
Two adjacent /25 blocks covering 192.168.0.0/24 plus 192.168.1.0/24 aggregate exactly to 192.168.0.0/23, containing 512 addresses.
Assumptions and input details
1–100 IPv4 CIDRs. Host bits normalize to their network address and duplicate or overlapping inputs do not double-count addresses. The exact union excludes holes; the separately shown single supernet may add addresses. Address counts include all endpoints without treating any as usable hosts. This page does not configure routes, contact networks or authorize advertisements.
References: RFC 4632: CIDR prefixes and aggregation
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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