Network Input Fields
Valid IPv4 required
Valid mask required
Subnet IP List Generator
Use this tool to expand any CIDR block or subnet into a full list of usable IPv4 host addresses. Ideal for building network inventories, running bulk ping sweeps, configuring firewall checklists, and auditing IP allocations across your infrastructure.
Full Range Expansion
Host Inventory Ready
/0 to /32 Support
Copy & Download
How to Use the Subnet IP List Generator
What This Tool Does
This tool takes a network address and prefix length and generates every usable host IP in that range. Network and broadcast addresses are automatically excluded (except for /31 and /32 which follow RFC 3021). A /24 produces 254 addresses; a /29 produces 6.
Step-by-Step Instructions
- 1Enter IP Address: Type the network address (e.g.,
10.0.0.0). Any host IP in the range works — the tool finds the network boundary automatically. - 2Set the Prefix: Drag the CIDR slider or type the subnet mask (e.g.,
255.255.255.0) — both fields stay in sync. - 3Generate: Click Generate IP List to expand the range.
- 4Export: Use Copy for clipboard or Download to save a timestamped
.txtfile — one IP per line.
Caution: Subnets smaller than
/16 generate more than 65,000 addresses. For large ranges, use the Download button rather than copying to clipboard.Common Use Cases
| Use Case | How the List Helps |
|---|---|
| Ping Sweep | Feed the list into fping or nmap -iL to scan for live hosts. |
| Firewall ACLs | Enumerate every address that needs a permit/deny entry in a host-by-host rule set. |
| DHCP Audit | Cross-reference against your DHCP lease table to find unassigned or rogue addresses. |
| Asset Inventory | Import into a spreadsheet or CMDB as the base list for device discovery. |
Frequently Asked Questions
Are the network and broadcast addresses included?
No. For standard subnets (/0 through /30) the tool excludes the network address (first IP) and the broadcast address (last IP) and lists only the usable host range. For /31 point-to-point links both addresses are included per RFC 3021, and for /32 the single host address is returned.
What is the maximum subnet size I can generate?
The tool supports up to /0 in theory, but generating a list for anything smaller than /8 (16 million+ addresses) is impractical in a browser. For production-scale ranges, generate a /24 block at a time and concatenate the files, or use command-line tools like prips or nmap.
Can I enter a host IP instead of the network address?
Yes. If you enter 192.168.1.50 with a /24 mask, the tool applies the subnet mask to find the network address (192.168.1.0) and generates the list from there. You don't need to manually calculate the network boundary first.
Does the Download save a CSV?
No — it saves a plain .txt file with one IP per line. This format is directly compatible with nmap -iL, fping, most firewall import tools, and spreadsheet imports without any additional formatting.
How do the IP Address and Subnet Mask fields stay in sync?
All three inputs — IP address, subnet mask, and CIDR slider — are linked. Dragging the slider auto-fills the mask field. Typing a valid mask auto-moves the slider. This prevents mismatches between the mask and prefix that would produce an incorrect range.