Nth Address Calculator
Find an address by range offset.
Nth Address Calculator: inputs and results
Enter an IP address, CIDR prefix, or range. Then check its first and last address below.
Calculated Boundaries & ParametersReady
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.
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IPv4 Broadcast Address Calculator
Find broadcast addresses where applicable.
First and Last Address Calculator
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Usable IPv4 Host Range Calculator
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How Nth Address Calculator Works?
This tool works by adding an offset to the first address of a range and checking that the result stays inside the range. Offset 0 returns the first address.
Enter the range or CIDR
Type
192.168.0.0/22or a start–end range.Enter the offset
Type a position such as 1,000. Negative offsets count back from the last address.
Add the offset
The calculator adds the offset to the 32-bit start value:
start + 1,000.Check the bounds
Results beyond the last address are flagged as out of range.
Nth Address Calculator Formula
The formula is Address(n) = Start + n, valid while 0 ≤ n ≤ Size − 1.
Forward offset
A(n) = Start + nOffset 0 is the first address.
Backward offset
A(−k) = End − (k − 1)Offset −1 is the last address.
Valid offsets
0 ≤ n ≤ 2^(32−p) − 1A /22 accepts offsets 0 to 1,023.
Octet split
n = 256 × q + r → +q in octet 3, +r in octet 4Carries move left across octets.
Worked example: offset 1,000 in 192.168.0.0/22
1,000 = 3 × 256 + 232 Start = 192.168.0.0 Add 3 to octet 3 and 232 to octet 4 Result = 192.168.3.232 (inside 192.168.0.0 – 192.168.3.255 ✓)
Nth Address Calculator Conversion Table
The table lists the address at 13 offsets inside 192.168.0.0/22, including the last valid offset and 1 out-of-range offset.
| Offset (n) | Address | Status |
|---|---|---|
| 0 | 192.168.0.0 | First address |
| 1 | 192.168.0.1 | In range |
| 2 | 192.168.0.2 | In range |
| 10 | 192.168.0.10 | In range |
| 100 | 192.168.0.100 | In range |
| 254 | 192.168.0.254 | In range |
| 255 | 192.168.0.255 | In range |
| 256 | 192.168.1.0 | In range |
| 500 | 192.168.1.244 | In range |
| 512 | 192.168.2.0 | In range |
| 1,000 | 192.168.3.232 | In range |
| 1,023 | 192.168.3.255 | Last address |
| 1,024 | 192.168.4.0 | Out of range |
What is Nth Address Calculator?
The Nth Address Calculator is a tool that returns the address found at a given position inside an IPv4 range or subnet. Position 0 is the first address, and position 1 is the next address.
Offsets cross octet boundaries automatically. Offset 256 in 192.168.0.0/22 lands on 192.168.1.0, not on an invalid 192.168.0.256. The calculator handles every carry across all 4 octets.
Addressing standards often place devices at fixed positions, such as the 10th address for a firewall or the 5th-from-last address for a management switch. The Nth Address Calculator finds those addresses in any subnet size.
What are the uses of Nth Address Calculator?
There are 5 main uses of the Nth Address Calculator, including template addressing, automation, and lab setup.
Applying address templates
Site templates assign the gateway to offset 1, the firewall to offset 2, and printers to offsets 20 to 29.
Generating IPs in automation
Ansible and Terraform templates compute
cidrhost(prefix, n). The calculator checks those values by hand.Placing load balancer VIPs
Virtual IPs often sit at fixed offsets near the end of a subnet, such as offset −10.
Building lab networks
Lab guides assign host 1 to host N in order. The calculator gives each lab host its address.
Checking offset bounds
The calculator warns before a template assigns an address beyond the subnet end.