CIDR Range Expander
Expand IPv4 CIDR ranges into IP addresses, calculate subnet details, and copy clean IP lists directly in your browser.
Enter one IPv4 CIDR block such as 192.168.1.0/29, 10.0.0.0/30, or 172.16.5.128/28 to expand it into individual IP addresses.
Expansion Options
The browser output is limited to 65,536 addresses to avoid freezing very large CIDR ranges.
Expanded IP Output
Expanded IP addresses will appear here.
Expanding CIDR Blocks Into Individual IP Addresses
CIDR notation is a compact way to describe a group of IP addresses. It is common in firewall rules, cloud networking, allowlists, routing tables, security groups, access control lists, and network documentation. A value like 192.168.1.0/29 represents a range, not just a single address.
This CIDR Range Expander converts IPv4 CIDR blocks into individual IP addresses and also shows important subnet details. It helps when you need to review a subnet, prepare an allowlist, check firewall entries, debug access rules, or understand exactly which addresses a CIDR block covers.
Expanding a CIDR Range Without Manual Subnet Math
- Enter an IPv4 CIDR block into the input field.
- Select whether network and broadcast addresses should be included.
- Choose line list, CSV, or JSON output format.
- Click Expand CIDR and copy the generated IP list.
Common CIDR Range Expander Use Cases
- Checking which IP addresses are covered by a CIDR block.
- Preparing firewall, WAF, VPN, or proxy allowlists.
- Reviewing cloud security group and network ACL ranges.
- Debugging subnet allocation and address planning issues.
- Converting CIDR notation into CSV or JSON for scripts and tools.
- Documenting internal network ranges for operations teams.
Example CIDR Expansion
Input: 192.168.1.0/29 Output without network and broadcast: 192.168.1.1 192.168.1.2 192.168.1.3 192.168.1.4 192.168.1.5 192.168.1.6 Details: Network: 192.168.1.0 Broadcast: 192.168.1.7 Subnet mask: 255.255.255.248 Total addresses: 8 Usable addresses: 6
Understanding Network and Broadcast Addresses
In traditional IPv4 subnetting, the first address in a subnet is the network address and the last address is the broadcast address. These two addresses are usually not assigned to hosts in normal subnet planning, which is why the tool can exclude them by default.
Some modern cloud and point-to-point networking situations may treat addresses differently, so the tool lets you include the network and broadcast addresses when you need the full raw range.
Frequently Asked Questions
What does a CIDR range mean?
A CIDR range describes a group of IP addresses using an address and prefix length. For example, 192.168.1.0/29 represents 8 total IPv4 addresses.
Does this support IPv6 CIDR ranges?
This version focuses on IPv4 CIDR expansion. IPv6 ranges can be extremely large, so they need a different interface and safety limits.
Why is there an expansion limit?
Large CIDR ranges can contain millions of addresses. The tool limits expansion to keep the browser responsive and prevent very large accidental output.
Can I include network and broadcast addresses?
Yes. Enable the option to include the first and last addresses of the range in the expanded output.
Are my IP ranges uploaded anywhere?
No. CIDR expansion happens directly in your browser, and your IP ranges are not uploaded to a server.