IP Range Calculator

Find the first and last usable address in any block.

Free
No signup
Nothing uploaded
No watermark

IP address with a prefix or a mask

Network

192.168.1.128

Broadcast

192.168.1.191

Usable hosts

Subnet mask

255.255.255.192

Address: 192.168.1.130
Prefix: /26
Host range: 192.168.1.129 – 192.168.1.190
Wildcard mask: 0.0.0.63used by Cisco ACLs — the inverse of the subnet mask
Total addresses: 64
Address class: Chistorical — classless routing replaced this in 1993
Scope: Private (RFC 1918) — the usual home router range
Address in binary: 11000000.10101000.00000001.10000010
Mask in binary: 11111111.11111111.11111111.11000000

Split this block into smaller subnets

How to Use the IP Range Calculator Online

Finds the first and last usable address in a block, which is what you need when allocating a DHCP pool or a static range. The first usable is one above the network address and the last is one below the broadcast — both boundaries being the addresses that cannot be handed out.

No software to install Free Works on any device

Step-by-Step Guide to Using the IP Range Calculator

1

1. Type an address, with a prefix or a mask
2

2. Everything is worked out as you type — network, broadcast, range and host count
3

3. It is pure arithmetic, so it works on private ranges and networks that do not exist yet

Try it now

What is the IP Range Calculator?

Why Use IP and Network Calculators?

Subnet masks, CIDR ranges and download times all come down to binary maths that is easy to slip on. These calculators do the sums in the page, so you can plan an address range or check a speed claim with confidence.

“One wrong subnet mask can take a whole office offline.”

Subnets worked out instantly
CIDR ranges made clear
Download times estimated
Browser details revealed

Usable host counts shown
IPv4 and IPv6 conversions
MAC addresses checked
No commands to install

Popular Uses for Subnet Calculators

Network jobs at home and at work often start with one of these sums.

Planning an office network Split an address block into subnets for each floor, team or guest WiFi.
Reading CIDR notation See the first address, last address and host count behind a range like /24.
Download estimates Work out how long a large file will take on a given connection speed.
Speed claims Turn megabits per second into megabytes to see what a plan really delivers.
Device lookups Find the maker of a network card from its MAC address prefix.
Browser checks See your user agent and browser details when a support team asks.
WebSocket tests Connect to a WebSocket endpoint and watch messages go back and forth.
IPv6 planning Convert an IPv4 address into IPv6 form while preparing a migration.

What You Can Do with the IP Range Calculator

Handles /31 and /32 correctly, not just the common cases

Shows the network, broadcast and usable host range together, which is the whole answer

Handles IPv6 at full length rather than truncating it for display

Why Use ToolXkit for IP Range Calculator?

Your files stay with you

Everything runs inside your browser. Nothing you open or type is uploaded to a server.

Network Tools for Different Users

Network administrators

Plan subnets, check CIDR ranges and size links for expected bandwidth.

Networking students

Practise subnetting for CCNA and other exams, and check answers quickly.

Developers

Test WebSocket servers, parse user agents and inspect TCP header fields.

IT support staff

Collect browser details and estimate transfer times while helping users.

Small office owners

Understand router settings and IP ranges without calling a technician every time.

Streamers and gamers

Check upload speed, latency and packet loss figures before a stream.

Best Times to Work Out a Subnet

Network calculators help when you are:

Setting up a new router
Studying for a networking exam
Adding a guest WiFi network
Estimating a large upload
Comparing broadband plans
Identifying an unknown device
Moving to IPv6
Debugging a WebSocket connection

Frequently Asked Questions

Answers to common questions about this tool.

How do I split a block into smaller ranges?

Extend the prefix length. A /24 splits into two /25s, four /26s or eight /27s, each starting where the previous one ended. This is how a DHCP pool, a static range and a reserved block are carved out of one allocation without overlapping.

Which addresses should I keep out of the DHCP pool?

The gateway, any servers, printers and network equipment with fixed addresses, and a margin for future ones. The usual convention is to reserve the low addresses for infrastructure and start the pool above them, which keeps the two from colliding as the network grows.

Is IP Range Calculator accurate enough for real network work?

The maths behind addresses and ranges is exact, so the results match what a router expects. Double-check the input, especially the prefix length, since one wrong digit changes the whole range.

Do the calculators scan my network?

No. The subnet and speed calculators only work with the numbers you type in. They send no traffic into your network, and the only tool that connects anywhere is the WebSocket Tester, to the address you enter.

Why is my real download slower than the estimate?

The calculator assumes the full connection speed is available. In practice, WiFi, other devices, server limits and protocol overhead eat into it, so real downloads often take somewhat longer.

Is IP Range Calculator free and private?

Yes. It costs nothing and needs no account. What you type stays in your browser and is never sent to ToolXkit, which matters when it describes a real company network.

What is the difference between Mbps and MBps?

Mbps means megabits per second, the unit broadband plans use. MBps means megabytes per second, the unit most download windows show. One byte is eight bits, so 100 Mbps is about 12.5 MBps.

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