CIDR aggregation
CIDR aggregation lets you deduplicate and minimally aggregate CIDRs without widening their union in your browser.
IP range ⇔ CIDR
IP range ⇔ CIDR lets you convert IPv4 or IPv6 ranges to and from minimal CIDR sets in your browser.
IP range ⇔ CIDR
⌂ Inputs and results stay in this browser and are not automatically stored or sent.
Waiting for input
Input and conditions
Calculations use your input only; no network queries or configuration changes.
Output
Waiting for input
Complete text result
How to use
Enter start and end addresses of the same IP version to convert a range to CIDRs, or inspect the range represented by a CIDR.
Several CIDRs can be the correct answer. Check exact coverage without gaps or extra addresses; forcing one larger CIDR can unintentionally widen an allowlist.
Examples
192.0.2.0
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192.0.2.255Principles and limits
Each input is limited to 1,048,576 bytes, output to 33,554,432 bytes, and processing to 5,000 ms. Input is never silently truncated.
Guides
Related tools
IP and CIDR comparison
IP and CIDR comparison lets you calculate CIDR containment, overlap, intersection, and directional differences in your browser.