IPv4 subnet calculator
Calculate network address, broadcast address, usable range, and host count from CIDR notation.
Try a worked example
Try a worked example
Calculate network address, broadcast address, usable range, and host count from CIDR notation.
Check the units and options, then use the tool’s calculation button. The example is fictitious; replace its values for your own calculation.
Illustration only. Supply the applicable rates and assumptions yourself; this is not financial, tax or legal advice.
Example input
- IPv4 address / prefix
- 192.168.1.0/24
Expected output
Network address: 192.168.1.0 Broadcast address: 192.168.1.255 Prefix length: /24 Total addresses: 256 Usable host addresses: 254 Usable range: 192.168.1.1 – 192.168.1.254
Derives IPv4 address ranges from CIDR, with point-to-point /31 and host-route /32 conventions shown separately.
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Method and limits
This tool calculates IPv4 ranges only. It does not check address availability, configure equipment, or support IPv6. A /31 uses point-to-point conventions; a /32 represents one host route. Confirm the network context before applying a result.
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Quick answer
Derives IPv4 address ranges from CIDR, with point-to-point /31 and host-route /32 conventions shown separately.
The page code is downloaded when you open it; values are handled in your browser.
Limits of the result
This tool calculates IPv4 ranges only. It does not check address availability, configure equipment, or support IPv6. A /31 uses point-to-point conventions; a /32 represents one host route. Confirm the network context before applying a result.
Frequently asked questions
What does the calculation include?
For ordinary prefixes, the calculator identifies the network and broadcast addresses and counts the addresses between them as usable hosts. On a point-to-point /31, both addresses are host endpoints and there is no broadcast; a /32 is one host route with no broadcast. For example, 192.168.1.0/24 has 256 total and 254 usable addresses (.1–.254). Verify the network context and equipment support before applying a range to a live network.
What should I enter?
Enter an IPv4 address and its CIDR prefix, such as 192.168.1.0/24. This example contains 256 addresses: network 192.168.1.0, broadcast 192.168.1.255, and 254 ordinary host addresses from 192.168.1.1 to 192.168.1.254.
Does the result show which addresses are free?
No. The calculation describes an address range; it does not scan the network or identify addresses already assigned to devices.
Sources and references
These references describe the cited context and rules; some apply only in the jurisdiction named in their title. They do not validate this illustrative calculation.