IP Range Calculator - Network Scope Utility
Calculate start and end IP addresses for a given range.
Data Privacy & Security
100% Local Processing. Your data never leaves your browser. All calculations are securely executed using client-side JavaScript.
How to Use Ip Range Calculator
- Input the network IP address and the associated CIDR prefix or subnet mask.
- Click the calculate button to trigger the local bitwise evaluation.
- Review the first usable host, last usable host, network address, and broadcast address instantly.
Tool Limitations & Specs
- Operates exclusively via DOM-level JavaScript without server validation.
- Inputs exceeding standard format lengths will be securely rejected.
- Does not interact with external DNS or ICMP systems.
- Requires HTML5 Canvas and modern browser capabilities.
Frequently Asked Questions
What is an IP range?
An IP range represents the sequence of usable IP addresses within a specific subnet, starting after the network address and ending just before the broadcast address.
How do you find the first usable IP in a range?
The first usable IP address is calculated by taking the base network address (which identifies the subnet) and adding exactly 1 to the final octet.
How do you find the last usable IP in a range?
The last usable IP address is determined by taking the subnet broadcast address (the absolute highest IP in the block) and subtracting exactly 1.
Why are the network and broadcast addresses not usable?
By strict IPv4 protocol design, the first address identifies the network itself for routing tables, and the last address is used to broadcast packets to every device on that network.
What is the IP range for a /24 network?
A /24 network has 256 total IPs. The first is the network, the last is broadcast, leaving 254 usable IPs ranging from x.x.x.1 to x.x.x.254.
Can I calculate the range for a /32 subnet?
A /32 subnet isolates a single specific host. The network, broadcast, and usable IP address are all exactly the same single IP.
How do I combine multiple IP ranges?
Combining ranges requires route summarization or supernetting, where you decrease the CIDR prefix (e.g., merging two /24 blocks into a single /23 block).
Is this calculator safe for internal enterprise IPs?
Yes. The calculation happens 100% locally in your web browser. The tool never sends your enterprise subnets to a remote server for evaluation.