🚀 Experience the new and improved APIVoid! Check out what's new

IP CIDR Calculator

Calculate IP CIDR subnets with this free online tool. Enter a CIDR like 192.168.0.0/24 or 2001:db8::/126 in the input below and instantly view the start IP, end IP, total IP count, and network range details. We also have a new tool to check if an IP is in a CIDR range.

IPv4 Subnets Table

Prefix Size Network Mask Usable Hosts per Subnet
/1 128.0.0.0 2,147,483,646
/2 192.0.0.0 1,073,741,822
/3 224.0.0.0 536,870,910
/4 240.0.0.0 268,435,454
/5 248.0.0.0 134,217,726
/6 252.0.0.0 67,108,862
/7 254.0.0.0 33,554,430
/8 255.0.0.0 16,777,214
/9 255.128.0.0 8,388,606
/10 255.192.0.0 4,194,302
/11 255.224.0.0 2,097,150
/12 255.240.0.0 1,048,574
/13 255.248.0.0 524,286
/14 255.252.0.0 262,142
/15 255.254.0.0 131,070
/16 255.255.0.0 65,534
/17 255.255.128.0 32,766
/18 255.255.192.0 16,382
/19 255.255.224.0 8,190
/20 255.255.240.0 4,094
/21 255.255.248.0 2,046
/22 255.255.252.0 1,022
/23 255.255.254.0 510
/24 255.255.255.0 254
/25 255.255.255.128 126
/26 255.255.255.192 62
/27 255.255.255.224 30
/28 255.255.255.240 14
/29 255.255.255.248 6
/30 255.255.255.252 2
/31 255.255.255.254 0
/32 255.255.255.255 0

More Free Network Tools

Make sure to check out our other free related tools below—they can simplify your daily work, save time, and boost your productivity.

IP Reputation Check

Check if an IPv4 or IPv6 address is blacklisted with this online IP reputation check tool.

View Details

Domain Reputation Check

Check if a domain (e.g google.com) is blacklisted with this online domain reputation check tool.

View Details

Disposable Email Check

Check if an email belongs to a disposable or temporary email service with this online email checker.

View Details

Website Trust Score

A free online website trustworthiness check tool you can use to check the safety of web shops.

View Details

URL Reputation Check

Check if an URL is potentially suspicious (risk score) with this online URL reputation check tool.

View Details

SSL Certificate Check

With this online SSL certificate check tool you can view and verify SSL certificate of any website.

View Details

Start using our API services, it takes just a few minutes

Create your account, pick a subscription plan, and make your first API call instantly with your API key—simple as that!

Get started now