CIDR Subnet Calculator
Calculate network, broadcast, mask, wildcard, and host range for any IPv4 or IPv6 CIDR block. Pure math, runs in your browser.
CIDR Subnet Calculator — Paste any IP address with a CIDR prefix (like 192.168.1.0/24 or 2001:db8::/64) and see the network, broadcast, mask, wildcard, and usable host range. Works for both IPv4 and IPv6.
Calculation runs locally in your browser. No network calls.
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What is cidr subnet calculator?
Paste any IP address with a CIDR prefix (like 192.168.1.0/24 or 2001:db8::/64) and see the network, broadcast, mask, wildcard, and usable host range. Works for both IPv4 and IPv6.
Pure math — no network calls. Useful for planning network ranges, configuring firewalls, or learning subnetting.
How to use it
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Type an IP with a prefix
Format: IP/prefix, e.g. 10.0.0.0/8 or 2001:db8::/32.
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Read the result
Network address, mask, wildcard, broadcast (IPv4), and usable host count are shown. For IPv6, the total address count is shown (it is usually astronomically large).
Frequently asked questions
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