IP Range to CIDR Converter
Type a start and end IP to get the exact CIDR blocks that cover it — nothing more, nothing less.
Help shape IP Range to CIDR Converter
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Frequently Asked Questions
CIDR blocks must start on a boundary matching their size, so an arbitrary range is covered by a mix of block sizes.
Yes. Use CIDR list tools and choose Summarize — overlapping and adjacent blocks are merged.
Yes, IPv4 and IPv6 are both supported.
Up to 20,000 list entries and 5,000 output blocks, all computed in your browser.
No. All subnet math runs in your browser. The IPs and networks you enter never leave your device.
No. All subnet math runs in your browser. The IPs and networks you enter never leave your device.