IPv4 Range Expander
Expand a CIDR block or IP range into a full list of every individual address it contains.
8 addresses
Recommended Settings
Pro Tips
- •Accepts three input formats: CIDR notation (192.168.1.0/24), a start-end range (192.168.1.1-192.168.1.10), or a single IP
- •A /24 CIDR expands to 256 addresses, a /16 to 65,536 - very small prefixes can produce enormous lists, so output is capped for browser performance
- •The expanded list includes the network and broadcast addresses for CIDR input - filter those out separately if you only need usable host addresses
- •Use this to generate a plain-text IP list for a firewall rule, allowlist, or documentation
Most Popular
Most people expand a small CIDR block (/28 or /29) to get a full list of addresses for a firewall or access control rule
When to Use This Tool
Get every individual address in a small CIDR block for a firewall or access rule.
See every address that falls within a given subnet or IP range.
Generate a plain-text list of addresses to paste into a firewall or router configuration.
Confirm exactly which addresses are included at the start and end of a range.
How It Works
Parse the input as a CIDR block, an explicit IP range, or a single address
Convert the range's start and end addresses into 32-bit integers
Increment through every integer in that range, converting each back into dotted decimal notation
100% Private
Files never leave your device. All processing happens locally in your browser.
Lightning Fast
Powered by Client-side 32-bit IPv4 arithmetic for optimal performance on modern browsers.
Open Source
Built with verified, open-source libraries. Fully transparent.
Frequently Asked Questions
Why is the output capped?
A CIDR block as small as /8 contains over 16 million addresses - generating and rendering a list that large would freeze your browser, so output is capped at a reasonable size.
Does this include the network and broadcast addresses?
Yes, for CIDR input the full range including the network and broadcast addresses is listed - remove the first and last entries if you only need usable host addresses.
Can I expand a reverse range (higher to lower)?
No, the start address of an explicit range must come before or equal to the end address.
Is my IP data sent anywhere?
No. All expansion happens locally in your browser.