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IP Range CalculatorPRO
IPv4 Subnetting & RangeInstant Client-Side Tool

Next Subnet Calculator

Find the following same-sized subnet.

Next 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.

IPv4 Subnet Calculator

Calculate subnet details from address and mask.

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.

How Next Subnet Calculator Works?

This tool works by adding the block size of a subnet to its network address, which returns the next subnet of the same size.

  1. Enter a subnet

    Type a CIDR block such as 10.1.4.0/22.

  2. Align the network

    The calculator rounds the address down to the network address of the prefix.

  3. Add the block size

    A /22 holds 1,024 addresses, so the calculator adds 1,024 to the network address.

  4. Return the next block

    The result, 10.1.8.0/22, keeps the same prefix length. An overflow past 255.255.255.255 returns no result.

Next Subnet Calculator Formula

The formula is Next Network = Network + 2^(32 − p).

Next network

N_next = N + 2^(32−p)

Same prefix length p.

Next broadcast

B_next = N_next + 2^(32−p) − 1

End of the next block.

Kth next subnet

N_k = N + k × 2^(32−p)

Skips k blocks forward.

Overflow check

N_next ≤ 2^32 − 2^(32−p)

No next subnet exists past the end of IPv4 space.

Worked example: 10.1.4.0/22

Block size  = 2^10 = 1,024 = 4 × /24
Next        = 10.1.4.0 + 4 in octet 3 = 10.1.8.0/22
Next range  = 10.1.8.0 – 10.1.11.255
3rd next    = 10.1.4.0 + 3 × 1,024 = 10.1.16.0/22

Next Subnet Calculator Conversion Table

The table lists the next subnet and its range for 10 starting subnets of different sizes.

Current SubnetBlock SizeNext SubnetNext Range
10.1.4.0/221,02410.1.8.0/2210.1.8.0 – 10.1.11.255
192.168.1.0/24256192.168.2.0/24192.168.2.0 – 192.168.2.255
192.168.1.128/25128192.168.2.0/25192.168.2.0 – 192.168.2.127
172.16.32.0/198,192172.16.64.0/19172.16.64.0 – 172.16.95.255
10.0.0.0/816,777,21611.0.0.0/811.0.0.0 – 11.255.255.255
10.200.10.64/266410.200.10.128/2610.200.10.128 – 10.200.10.191
203.0.113.240/2816203.0.114.0/28203.0.114.0 – 203.0.114.15
198.51.100.252/304198.51.101.0/30198.51.101.0 – 198.51.101.3
172.31.255.0/24256172.32.0.0/24172.32.0.0 – 172.32.0.255
100.64.0.0/104,194,304100.128.0.0/10100.128.0.0 – 100.191.255.255

What is Next Subnet Calculator?

The Next Subnet Calculator is a tool that returns the subnet immediately after a given subnet, using the same prefix length. The next /24 after 192.168.1.0/24 is 192.168.2.0/24.

Subnets of the same size sit side by side with no gap. The next subnet starts exactly 1 address after the broadcast address of the current subnet. The calculator finds that start for any prefix from /1 to /32.

Sequential allocation is the most common way to hand out address space. The Next Subnet Calculator gives the next block in the sequence without manual octet math.

What are the uses of Next Subnet Calculator?

There are 4 main uses of the Next Subnet Calculator, including sequential allocation, VLAN numbering, and lab design.

  • Allocating subnets in order

    Teams assign the next free /24 to each new VLAN. The calculator returns that /24.

  • Numbering new sites

    Each new branch gets the next /22 from the regional block.

  • Planning cloud subnet sequences

    VPC designs assign one subnet per Availability Zone in order. The calculator gives each block.

  • Building exam answers

    Subnetting exams ask for "the 3rd subnet" or "the next valid subnet". The calculator checks the answer.