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IP Range CalculatorPRO
IPv4 Subnetting & RangeInstant Client-Side Tool

IPv4 Subnet Calculator

Calculate subnet details from address and mask.

IPv4 Subnet Calculator: inputs and results

Enter an IP address, CIDR prefix, or range. Then check its first and last address below.

Quick presets:

Calculated Boundaries & ParametersReady

Network Address192.168.1.0
Broadcast Address192.168.1.255
First Usable Host192.168.1.1
Last Usable Host192.168.1.254
Subnet Mask255.255.255.0
Wildcard Mask0.0.0.255
Total Addresses256
Usable Host Range254

Key Capabilities

  • •100% Client-Side: Zero telemetry or server latency.
  • •RFC Compliant: Exact 32-bit and 128-bit integer precision.
  • •Quick Copy: Instant access to CIDR, mask, and range bounds.
  • •Cross-Platform: Works on desktop, tablet, and mobile browsers.
Open Full Interactive Suite

Related IPv4 Subnetting & RangeAll Tools

IPv4 Range Calculator

Find address boundaries from a prefix.

Network Address Calculator

Find the subnet’s network address.

IPv4 Broadcast Address Calculator

Find broadcast addresses where applicable.

First and Last Address Calculator

Identify a range’s endpoints.

Usable IPv4 Host Range Calculator

Apply the selected subnet-use rules.

Total Address Count Calculator

Count addresses within a prefix.

How IPv4 Subnet Calculator Works?

This tool works by combining an address with a subnet mask and deriving 8 values: network address, broadcast address, first host, last host, subnet mask, wildcard mask, total addresses, and usable hosts.

  1. Enter an address and mask

    Type an address such as 192.168.50.77 and pick a mask in dotted form (255.255.255.224) or CIDR form (/27).

  2. Validate the mask

    The calculator confirms that the mask has contiguous 1 bits followed by contiguous 0 bits. A mask such as 255.0.255.0 fails this check.

  3. Compute the subnet boundaries

    The network address comes from IP AND mask. The broadcast address comes from network OR wildcard.

  4. List hosts and counts

    Usable hosts sit between network + 1 and broadcast − 1. /31 and /32 prefixes follow RFC 3021 and host-route rules instead.

IPv4 Subnet Calculator Formula

The formula set is Network = IP AND Mask, Broadcast = Network OR Wildcard, and Usable Hosts = 2^(32 − p) − 2.

Network address

Network = IP AND Mask

Bitwise AND across all 32 bits.

Wildcard mask

Wildcard = 255.255.255.255 − Mask

Each octet of the wildcard is 255 minus the matching mask octet.

Broadcast address

Broadcast = Network OR Wildcard

Sets every host bit to 1.

Usable hosts

Usable = 2^(32 − p) − 2

Valid for /0 to /30. A /31 has 2 usable addresses and a /32 has 1.

Worked example: 192.168.50.77 with 255.255.255.224 (/27)

Last octet 77  = 01001101
Mask octet 224 = 11100000
AND            = 01000000 = 64   → Network   192.168.50.64
Wildcard       = 0.0.0.31        → Broadcast 192.168.50.95
Host range     = 192.168.50.65 – 192.168.50.94
Usable hosts   = 2^5 − 2 = 30

IPv4 Subnet Calculator Conversion Table

The table lists the network, broadcast, and usable host count for 192.168.50.77 under 10 different subnet masks.

Subnet MaskCIDRNetworkBroadcastUsable Hosts
255.255.248.0/21192.168.48.0192.168.55.2552,046
255.255.252.0/22192.168.48.0192.168.51.2551,022
255.255.254.0/23192.168.50.0192.168.51.255510
255.255.255.0/24192.168.50.0192.168.50.255254
255.255.255.128/25192.168.50.0192.168.50.127126
255.255.255.192/26192.168.50.64192.168.50.12762
255.255.255.224/27192.168.50.64192.168.50.9530
255.255.255.240/28192.168.50.64192.168.50.7914
255.255.255.248/29192.168.50.72192.168.50.796
255.255.255.252/30192.168.50.76192.168.50.792

What is IPv4 Subnet Calculator?

The IPv4 Subnet Calculator is a tool that returns every key property of an IPv4 subnet from one address and one subnet mask. The output covers the network address, broadcast address, host range, wildcard mask, and host counts in a single view.

Subnetting divides a larger IPv4 network into smaller broadcast domains. Each subnet uses a mask, written as dotted decimal (255.255.255.224) or as a CIDR prefix (/27), to mark which of the 32 bits identify the network. The IPv4 Subnet Calculator reads either notation and produces identical results.

Network engineers, students preparing for the Cisco Certified Network Associate (CCNA) exam, and cloud architects use the IPv4 Subnet Calculator to configure interfaces, plan Virtual Local Area Networks (VLANs), and confirm address assignments before deployment.

What are the uses of IPv4 Subnet Calculator?

There are 6 main uses of the IPv4 Subnet Calculator, including interface configuration, VLAN design, and exam preparation.

  • Configuring router interfaces

    Router and Layer 3 switch interfaces need an address and a mask. The calculator confirms that the chosen address is a usable host, not the network or broadcast address.

  • Designing VLAN subnets

    Each VLAN maps to one subnet. The host count shows whether a /26 (62 hosts) or a /25 (126 hosts) fits the VLAN.

  • Setting DHCP scopes

    Dynamic Host Configuration Protocol (DHCP) pools must stay inside the usable host range. The first and last host values set the pool limits.

  • Troubleshooting connectivity

    Two hosts with mismatched masks often fail to reach each other. The calculator shows the subnet each host believes it belongs to.

  • Preparing for certification exams

    CCNA, CompTIA Network+, and JNCIA exams test subnet math. The calculator checks hand-worked answers in seconds.

  • Documenting network designs

    Design documents list network, mask, gateway, and broadcast for each segment. The calculator output fills those fields directly.