What does CIDR summarization do?
It converts a continuous IP range into one or more network prefixes that cover the same addresses.
Security
IP Range Calculator
Calculate IP ranges, address counts and CIDR coverage for IPv4 and IPv6.
Tool
IP Range Calculator
Calculate IP ranges, address counts and CIDR coverage for IPv4 and IPv6.
This tool runs in your browser. Your input is processed locally and is not uploaded.
About this Tool
Use this IP range calculator to validate IPv4 or IPv6 ranges, count included addresses and summarize the range into the smallest practical set of CIDR blocks. No network lookup is performed.
Examples
- 192.168.1.1 - 192.168.1.254
- 10.0.0.0 - 10.0.3.255
- 2001:db8:: - 2001:db8::ffff
Frequently Asked Questions
Can IPv4 and IPv6 be mixed?
No. The start and end addresses must use the same IP version.
Does the tool test whether addresses are reachable?
No. It performs mathematical range calculations only.