CIDR Subnet Calculator
Compute the network and broadcast address, subnet mask, wildcard mask, usable host range and host count from an IPv4 CIDR like 192.168.1.0/24.
Usable range: —
Octets in hex? Base converter · binary view: Binary translator.
How to use the CIDR calculator
Enter an IPv4 or IPv6 address with a prefix length. Choose general networking or AWS VPC reservation policy; IPv6 address totals are calculated exactly with BigInt.
FAQ
What does this calculate?
From an IPv4 or IPv6 address and CIDR prefix it computes the canonical network, masks, address range and exact BigInt-sized address count.
How are /31 and /32 handled?
Under RFC 3021, both /31 addresses are point-to-point endpoints and there is no directed broadcast. A /32 is displayed as one host with no broadcast address.
What does AWS VPC mode change?
AWS reserves the first four and last address of each IPv4 or IPv6 subnet. General IPv4 mode instead uses the conventional network/broadcast subtraction where applicable.
Is anything uploaded?
No. All calculations run in your browser.
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