IP subnet calculator
Find network boundaries and address counts for an IPv4 or IPv6 CIDR.
Bookmark this page
Keep this page handy for next time.
- On a computer
- Press Ctrl + D, or Command + D on a Mac.
- On a phone or tablet
- Open your browser's menu or Share menu and look for Add Bookmark, Bookmark or Add to favourites.
A bookmark saves the page link. Save any tool results separately.
How to use this tool
- Find network boundaries and address counts for an IPv4 or IPv6 CIDR.
- Adjust the labelled settings, then run the tool. Copy the result or download it as a file.
Things to know
- Processing is local. Supplied code and network requests are never executed. Input and text settings are limited to 5 MiB combined; text settings alone are limited to 1 MiB.
- One IPv4/IPv6 address and optional CIDR in 128 bytes. Arithmetic uses at most 128-bit addresses; address ranges are counted without enumerating addresses.
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