NetCalc

Simple CIDR & Subnet Calculator for VPCs and Azure VNets

Enter CIDR Block (e.g., 192.168.0.0/24):

Subnet Calculator

Enter VPC CIDR Block: Enter Number of Subnets:

📘 IP Address Info & Subnet Tables

Private IP Address Ranges

10.0.0.0 – 10.255.255.255 (A - 10.0.0.0/8 prefix)
172.16.0.0 – 172.31.255.255 (B - 172.16.0.0/12 prefix)
192.168.0.0 – 192.168.255.255 (C - 192.168.0.0/16 prefix)

Public IP Addresses

All other IPs outside the private ranges above are considered public IPs.

Special IP Addresses

127.0.0.0/8 - Loopback
169.254.0.0/16 - Link-local
224.0.0.0/4 - Multicast
240.0.0.0/4 - Reserved for future use

Common Subnet Prefixes

Prefix	Subnet Mask	# of Hosts
/0	0.0.0.0	4,294,967,296
/1	128.0.0.0	2,147,483,648
/2	192.0.0.0	1,073,741,824
/3	224.0.0.0	536,870,912
/4	240.0.0.0	268,435,456
/5	248.0.0.0	134,217,728
/6	252.0.0.0	67,108,864
/7	254.0.0.0	33,554,432
/8	255.0.0.0	16,777,216
/9	255.128.0.0	8,388,608
/10	255.192.0.0	4,194,304
/11	255.224.0.0	2,097,152
/12	255.240.0.0	1,048,576
/13	255.248.0.0	524,288
/14	255.252.0.0	262,144
/15	255.254.0.0	131,072
/16	255.255.0.0	65,536
/17	255.255.128.0	32,768
/18	255.255.192.0	16,384
/19	255.255.224.0	8,192
/20	255.255.240.0	4,096
/21	255.255.248.0	2,048
/22	255.255.252.0	1,024
/23	255.255.254.0	512
/24	255.255.255.0	256
/25	255.255.255.128	128
/26	255.255.255.192	64
/27	255.255.255.224	32
/28	255.255.255.240	16
/29	255.255.255.248	8
/30	255.255.255.252	4
/31	255.255.255.254	2
/32	255.255.255.255	1

Helpful Notes

/32 represents a single IP (host).
/30 is often used for point-to-point links.
/24 is common for typical small networks.

IP Address Classes

Class	Range	Default Subnet Mask	Purpose
A	1.0.0.0 – 126.255.255.255	255.0.0.0	Large networks
B	128.0.0.0 – 191.255.255.255	255.255.0.0	Medium-sized networks
C	192.0.0.0 – 223.255.255.255	255.255.255.0	Small networks
D	224.0.0.0 – 239.255.255.255	N/A	Multicast
E	240.0.0.0 – 255.255.255.255	N/A	Experimental