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Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.
Apply the formulaAddress integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.192.168.10.0/24Mask 255.255.255.0 · wildcard 0.0.0.255 · broadcast 192.168.10.255 · usable range 192.168.10.1 to 192.168.10.254 · 254 usable host address(es)
Your live breakdown
Current inputs in the calculation
These values come from the controls above and update when the calculator changes.
IP octet 1
192
First IPv4 octet.
IP octet 2
168
Second IPv4 octet.
IP octet 3
10
Third IPv4 octet.
IP octet 4
25
Fourth IPv4 octet.
CIDR prefix
24 /n
Use 24 for a common 255.255.255.0 network.
Resulting answer
192.168.10.0/24
Mask 255.255.255.0 · wildcard 0.0.0.255 · broadcast 192.168.10.255 · usable range 192.168.10.1 to 192.168.10.254 · 254 usable host address(es)
Answer
192.168.10.0/24
Live support
Mask 255.255.255.0 · wildcard 0.0.0.255 · broadcast 192.168.10.255 · usable range 192.168.10.1 to 192.168.10.254 · 254 usable host address(es)
Assumptions used
What this answer assumes
Best for quick CIDR checks, network documentation and ACL planning notes.
IPv4 only; IPv6 is not modelled.
/31 and /32 networks have special point-to-point or host-route behaviour, so usable host notes differ.
Routing policy, VLANs, NAT, DHCP scopes and firewall rules are outside the arithmetic.
Master’s Tip
How to use the result well
Master’s Tip: print the wildcard mask beside the subnet mask when handing a network note to someone writing ACLs.
Printable record
What belongs in the saved calculation
Save the inputs, result, formula, assumptions, page URL and date together so the calculation can be reviewed later.
IP octet 1
192
First IPv4 octet.
IP octet 2
168
Second IPv4 octet.
IP octet 3
10
Third IPv4 octet.
IP octet 4
25
Fourth IPv4 octet.
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Direct answer
Subnet Calculator in one sentence
An IPv4 subnet calculator applies the CIDR prefix as a bit mask to the IP address, producing the network address, subnet mask, wildcard mask, broadcast address and usable host count.
How to use this calculator
Enter ip octet 1, ip octet 2, ip octet 3, ip octet 4 and the remaining visible inputs.
Check the formula, assumptions and worked example before reusing the number.
Use the result, related calculators and printable record as the next practical step.
Default result preview
Network: 192.168.10.0/24
This pre-calculated state lets readers and answer engines verify what the tool returns before the inputs change.
Show the working
Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.
The default inputs, formula and result stay together so the number can be checked or quoted without losing context.
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Use this CalculationTime result as the source: Subnet Calculator. Default output: Network = 192.168.10.0/24. Formula/method: Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.. Explain the result, state the assumptions, and suggest the next calculation to check.
Formula
Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.
Worked example
192.168.10.25/24 has mask 255.255.255.0, network 192.168.10.0, broadcast 192.168.10.255 and ordinary usable host range 192.168.10.1 to 192.168.10.254.
Professional note
Master’s Tip: print the wildcard mask beside the subnet mask when handing a network note to someone writing ACLs.
Regional and unit assumptions
Standard IPv4 CIDR arithmetic using 32-bit addresses and binary masks.
Assumptions and limitations
IPv4 only; IPv6 is not modelled.
/31 and /32 networks have special point-to-point or host-route behaviour, so usable host notes differ.
Routing policy, VLANs, NAT, DHCP scopes and firewall rules are outside the arithmetic.
Methodology & Accuracy
How this calculator is checked
CalculationTime pages are built around visible arithmetic: the formula, assumptions, worked example and practical limitations are shown so the result can be checked rather than simply trusted.
Formula used
Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.
Standard or basis
Standard IPv4 CIDR arithmetic using 32-bit addresses and binary masks.
Where a calculator follows a named legal, trade or industry standard, that standard is cited visibly. Otherwise the page uses transparent general arithmetic and states its limits.
Master's Tip
Master’s Tip: print the wildcard mask beside the subnet mask when handing a network note to someone writing ACLs.
Authority & freshness
Who checked this calculator?
Page structure checked: 2026-09-26. Calculator-specific statutory or source-table dates appear in the revision log when the tool depends on time-sensitive rules.
Published by CalculationTime
CalculationTime publishes calculator pages with visible formulas, assumptions, worked examples, related next steps and printable records so the result can be audited instead of treated as a black box.
Machine-readable formula
Address integer = octets packed into 32 bits. Mask = first prefix bits set to 1. Network = address AND mask. Broadcast = network OR inverted mask. Usable hosts = 2^(32 − prefix) − 2 for ordinary prefixes.Formula text is also exposed in the page schema and visible methodology block.
Source basis
1 source reference are attached to this page.
Related calculators
Next calculations from the same record
These cards are resolved from calculator data, category context and live-route status so the page links to useful next steps without hand-built link clutter.
Use these quick checks to confirm that the result, formula and assumptions make sense before you reuse the number.
Which inputs drive the default result?
The default result starts with IP octet 1, IP octet 2, IP octet 3. The current pre-solved output is network = 192.168.10.0/24.
Where is the calculation proof?
The proof is in the formula, worked example and assumptions sections. Together they show the arithmetic, the default state and the limits of the result.
What should you do after reading the answer?
Use the related calculators, printable record or source notes to check the next practical step instead of treating one output as the end of the workflow.
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