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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network44.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
44.0.0.0
Broadcast address
44.63.255.255
First usable
44.0.0.1
Last usable
44.63.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 2C000000 · Integer 738197504 to 742391807
Reverse DNS zones
0.44.in-addr.arpa
1.44.in-addr.arpa
2.44.in-addr.arpa
3.44.in-addr.arpa
4.44.in-addr.arpa
5.44.in-addr.arpa
6.44.in-addr.arpa
7.44.in-addr.arpa
8.44.in-addr.arpa
9.44.in-addr.arpa
10.44.in-addr.arpa
11.44.in-addr.arpa
12.44.in-addr.arpa
13.44.in-addr.arpa
14.44.in-addr.arpa
15.44.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101100.00000000.00000000.0000000044.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00101100.00000000.00000000.0000000044.0.0.0
Broadcast00101100.00111111.11111111.1111111144.63.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

44.0.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
144.0.0.0/2244.0.0.1 to 44.0.3.25444.0.3.2551,022
244.0.4.0/2244.0.4.1 to 44.0.7.25444.0.7.2551,022
344.0.8.0/2244.0.8.1 to 44.0.11.25444.0.11.2551,022
444.0.12.0/2244.0.12.1 to 44.0.15.25444.0.15.2551,022
544.0.16.0/2244.0.16.1 to 44.0.19.25444.0.19.2551,022
644.0.20.0/2244.0.20.1 to 44.0.23.25444.0.23.2551,022
744.0.24.0/2244.0.24.1 to 44.0.27.25444.0.27.2551,022
844.0.28.0/2244.0.28.1 to 44.0.31.25444.0.31.2551,022
944.0.32.0/2244.0.32.1 to 44.0.35.25444.0.35.2551,022
1044.0.36.0/2244.0.36.1 to 44.0.39.25444.0.39.2551,022
1144.0.40.0/2244.0.40.1 to 44.0.43.25444.0.43.2551,022
1244.0.44.0/2244.0.44.1 to 44.0.47.25444.0.47.2551,022
1344.0.48.0/2244.0.48.1 to 44.0.51.25444.0.51.2551,022
1444.0.52.0/2244.0.52.1 to 44.0.55.25444.0.55.2551,022
1544.0.56.0/2244.0.56.1 to 44.0.59.25444.0.59.2551,022
1644.0.60.0/2244.0.60.1 to 44.0.63.25444.0.63.2551,022
1744.0.64.0/2244.0.64.1 to 44.0.67.25444.0.67.2551,022
1844.0.68.0/2244.0.68.1 to 44.0.71.25444.0.71.2551,022
1944.0.72.0/2244.0.72.1 to 44.0.75.25444.0.75.2551,022
2044.0.76.0/2244.0.76.1 to 44.0.79.25444.0.79.2551,022
2144.0.80.0/2244.0.80.1 to 44.0.83.25444.0.83.2551,022
2244.0.84.0/2244.0.84.1 to 44.0.87.25444.0.87.2551,022
2344.0.88.0/2244.0.88.1 to 44.0.91.25444.0.91.2551,022
2444.0.92.0/2244.0.92.1 to 44.0.95.25444.0.95.2551,022
2544.0.96.0/2244.0.96.1 to 44.0.99.25444.0.99.2551,022
2644.0.100.0/2244.0.100.1 to 44.0.103.25444.0.103.2551,022
2744.0.104.0/2244.0.104.1 to 44.0.107.25444.0.107.2551,022
2844.0.108.0/2244.0.108.1 to 44.0.111.25444.0.111.2551,022
2944.0.112.0/2244.0.112.1 to 44.0.115.25444.0.115.2551,022
3044.0.116.0/2244.0.116.1 to 44.0.119.25444.0.119.2551,022
3144.0.120.0/2244.0.120.1 to 44.0.123.25444.0.123.2551,022
3244.0.124.0/2244.0.124.1 to 44.0.127.25444.0.127.2551,022
3344.0.128.0/2244.0.128.1 to 44.0.131.25444.0.131.2551,022
3444.0.132.0/2244.0.132.1 to 44.0.135.25444.0.135.2551,022
3544.0.136.0/2244.0.136.1 to 44.0.139.25444.0.139.2551,022
3644.0.140.0/2244.0.140.1 to 44.0.143.25444.0.143.2551,022
3744.0.144.0/2244.0.144.1 to 44.0.147.25444.0.147.2551,022
3844.0.148.0/2244.0.148.1 to 44.0.151.25444.0.151.2551,022
3944.0.152.0/2244.0.152.1 to 44.0.155.25444.0.155.2551,022
4044.0.156.0/2244.0.156.1 to 44.0.159.25444.0.159.2551,022
4144.0.160.0/2244.0.160.1 to 44.0.163.25444.0.163.2551,022
4244.0.164.0/2244.0.164.1 to 44.0.167.25444.0.167.2551,022
4344.0.168.0/2244.0.168.1 to 44.0.171.25444.0.171.2551,022
4444.0.172.0/2244.0.172.1 to 44.0.175.25444.0.175.2551,022
4544.0.176.0/2244.0.176.1 to 44.0.179.25444.0.179.2551,022
4644.0.180.0/2244.0.180.1 to 44.0.183.25444.0.183.2551,022
4744.0.184.0/2244.0.184.1 to 44.0.187.25444.0.187.2551,022
4844.0.188.0/2244.0.188.1 to 44.0.191.25444.0.191.2551,022
4944.0.192.0/2244.0.192.1 to 44.0.195.25444.0.195.2551,022
5044.0.196.0/2244.0.196.1 to 44.0.199.25444.0.199.2551,022
5144.0.200.0/2244.0.200.1 to 44.0.203.25444.0.203.2551,022
5244.0.204.0/2244.0.204.1 to 44.0.207.25444.0.207.2551,022
5344.0.208.0/2244.0.208.1 to 44.0.211.25444.0.211.2551,022
5444.0.212.0/2244.0.212.1 to 44.0.215.25444.0.215.2551,022
5544.0.216.0/2244.0.216.1 to 44.0.219.25444.0.219.2551,022
5644.0.220.0/2244.0.220.1 to 44.0.223.25444.0.223.2551,022
5744.0.224.0/2244.0.224.1 to 44.0.227.25444.0.227.2551,022
5844.0.228.0/2244.0.228.1 to 44.0.231.25444.0.231.2551,022
5944.0.232.0/2244.0.232.1 to 44.0.235.25444.0.235.2551,022
6044.0.236.0/2244.0.236.1 to 44.0.239.25444.0.239.2551,022
6144.0.240.0/2244.0.240.1 to 44.0.243.25444.0.243.2551,022
6244.0.244.0/2244.0.244.1 to 44.0.247.25444.0.247.2551,022
6344.0.248.0/2244.0.248.1 to 44.0.251.25444.0.251.2551,022
6444.0.252.0/2244.0.252.1 to 44.0.255.25444.0.255.2551,022
6544.1.0.0/2244.1.0.1 to 44.1.3.25444.1.3.2551,022
6644.1.4.0/2244.1.4.1 to 44.1.7.25444.1.7.2551,022
6744.1.8.0/2244.1.8.1 to 44.1.11.25444.1.11.2551,022
6844.1.12.0/2244.1.12.1 to 44.1.15.25444.1.15.2551,022
6944.1.16.0/2244.1.16.1 to 44.1.19.25444.1.19.2551,022
7044.1.20.0/2244.1.20.1 to 44.1.23.25444.1.23.2551,022
7144.1.24.0/2244.1.24.1 to 44.1.27.25444.1.27.2551,022
7244.1.28.0/2244.1.28.1 to 44.1.31.25444.1.31.2551,022
7344.1.32.0/2244.1.32.1 to 44.1.35.25444.1.35.2551,022
7444.1.36.0/2244.1.36.1 to 44.1.39.25444.1.39.2551,022
7544.1.40.0/2244.1.40.1 to 44.1.43.25444.1.43.2551,022
7644.1.44.0/2244.1.44.1 to 44.1.47.25444.1.47.2551,022
7744.1.48.0/2244.1.48.1 to 44.1.51.25444.1.51.2551,022
7844.1.52.0/2244.1.52.1 to 44.1.55.25444.1.55.2551,022
7944.1.56.0/2244.1.56.1 to 44.1.59.25444.1.59.2551,022
8044.1.60.0/2244.1.60.1 to 44.1.63.25444.1.63.2551,022
8144.1.64.0/2244.1.64.1 to 44.1.67.25444.1.67.2551,022
8244.1.68.0/2244.1.68.1 to 44.1.71.25444.1.71.2551,022
8344.1.72.0/2244.1.72.1 to 44.1.75.25444.1.75.2551,022
8444.1.76.0/2244.1.76.1 to 44.1.79.25444.1.79.2551,022
8544.1.80.0/2244.1.80.1 to 44.1.83.25444.1.83.2551,022
8644.1.84.0/2244.1.84.1 to 44.1.87.25444.1.87.2551,022
8744.1.88.0/2244.1.88.1 to 44.1.91.25444.1.91.2551,022
8844.1.92.0/2244.1.92.1 to 44.1.95.25444.1.95.2551,022
8944.1.96.0/2244.1.96.1 to 44.1.99.25444.1.99.2551,022
9044.1.100.0/2244.1.100.1 to 44.1.103.25444.1.103.2551,022
9144.1.104.0/2244.1.104.1 to 44.1.107.25444.1.107.2551,022
9244.1.108.0/2244.1.108.1 to 44.1.111.25444.1.111.2551,022
9344.1.112.0/2244.1.112.1 to 44.1.115.25444.1.115.2551,022
9444.1.116.0/2244.1.116.1 to 44.1.119.25444.1.119.2551,022
9544.1.120.0/2244.1.120.1 to 44.1.123.25444.1.123.2551,022
9644.1.124.0/2244.1.124.1 to 44.1.127.25444.1.127.2551,022
9744.1.128.0/2244.1.128.1 to 44.1.131.25444.1.131.2551,022
9844.1.132.0/2244.1.132.1 to 44.1.135.25444.1.135.2551,022
9944.1.136.0/2244.1.136.1 to 44.1.139.25444.1.139.2551,022
10044.1.140.0/2244.1.140.1 to 44.1.143.25444.1.143.2551,022
10144.1.144.0/2244.1.144.1 to 44.1.147.25444.1.147.2551,022
10244.1.148.0/2244.1.148.1 to 44.1.151.25444.1.151.2551,022
10344.1.152.0/2244.1.152.1 to 44.1.155.25444.1.155.2551,022
10444.1.156.0/2244.1.156.1 to 44.1.159.25444.1.159.2551,022
10544.1.160.0/2244.1.160.1 to 44.1.163.25444.1.163.2551,022
10644.1.164.0/2244.1.164.1 to 44.1.167.25444.1.167.2551,022
10744.1.168.0/2244.1.168.1 to 44.1.171.25444.1.171.2551,022
10844.1.172.0/2244.1.172.1 to 44.1.175.25444.1.175.2551,022
10944.1.176.0/2244.1.176.1 to 44.1.179.25444.1.179.2551,022
11044.1.180.0/2244.1.180.1 to 44.1.183.25444.1.183.2551,022
11144.1.184.0/2244.1.184.1 to 44.1.187.25444.1.187.2551,022
11244.1.188.0/2244.1.188.1 to 44.1.191.25444.1.191.2551,022
11344.1.192.0/2244.1.192.1 to 44.1.195.25444.1.195.2551,022
11444.1.196.0/2244.1.196.1 to 44.1.199.25444.1.199.2551,022
11544.1.200.0/2244.1.200.1 to 44.1.203.25444.1.203.2551,022
11644.1.204.0/2244.1.204.1 to 44.1.207.25444.1.207.2551,022
11744.1.208.0/2244.1.208.1 to 44.1.211.25444.1.211.2551,022
11844.1.212.0/2244.1.212.1 to 44.1.215.25444.1.215.2551,022
11944.1.216.0/2244.1.216.1 to 44.1.219.25444.1.219.2551,022
12044.1.220.0/2244.1.220.1 to 44.1.223.25444.1.223.2551,022
12144.1.224.0/2244.1.224.1 to 44.1.227.25444.1.227.2551,022
12244.1.228.0/2244.1.228.1 to 44.1.231.25444.1.231.2551,022
12344.1.232.0/2244.1.232.1 to 44.1.235.25444.1.235.2551,022
12444.1.236.0/2244.1.236.1 to 44.1.239.25444.1.239.2551,022
12544.1.240.0/2244.1.240.1 to 44.1.243.25444.1.243.2551,022
12644.1.244.0/2244.1.244.1 to 44.1.247.25444.1.247.2551,022
12744.1.248.0/2244.1.248.1 to 44.1.251.25444.1.251.2551,022
12844.1.252.0/2244.1.252.1 to 44.1.255.25444.1.255.2551,022
12944.2.0.0/2244.2.0.1 to 44.2.3.25444.2.3.2551,022
13044.2.4.0/2244.2.4.1 to 44.2.7.25444.2.7.2551,022
13144.2.8.0/2244.2.8.1 to 44.2.11.25444.2.11.2551,022
13244.2.12.0/2244.2.12.1 to 44.2.15.25444.2.15.2551,022
13344.2.16.0/2244.2.16.1 to 44.2.19.25444.2.19.2551,022
13444.2.20.0/2244.2.20.1 to 44.2.23.25444.2.23.2551,022
13544.2.24.0/2244.2.24.1 to 44.2.27.25444.2.27.2551,022
13644.2.28.0/2244.2.28.1 to 44.2.31.25444.2.31.2551,022
13744.2.32.0/2244.2.32.1 to 44.2.35.25444.2.35.2551,022
13844.2.36.0/2244.2.36.1 to 44.2.39.25444.2.39.2551,022
13944.2.40.0/2244.2.40.1 to 44.2.43.25444.2.43.2551,022
14044.2.44.0/2244.2.44.1 to 44.2.47.25444.2.47.2551,022
14144.2.48.0/2244.2.48.1 to 44.2.51.25444.2.51.2551,022
14244.2.52.0/2244.2.52.1 to 44.2.55.25444.2.55.2551,022
14344.2.56.0/2244.2.56.1 to 44.2.59.25444.2.59.2551,022
14444.2.60.0/2244.2.60.1 to 44.2.63.25444.2.63.2551,022
14544.2.64.0/2244.2.64.1 to 44.2.67.25444.2.67.2551,022
14644.2.68.0/2244.2.68.1 to 44.2.71.25444.2.71.2551,022
14744.2.72.0/2244.2.72.1 to 44.2.75.25444.2.75.2551,022
14844.2.76.0/2244.2.76.1 to 44.2.79.25444.2.79.2551,022
14944.2.80.0/2244.2.80.1 to 44.2.83.25444.2.83.2551,022
15044.2.84.0/2244.2.84.1 to 44.2.87.25444.2.87.2551,022
15144.2.88.0/2244.2.88.1 to 44.2.91.25444.2.91.2551,022
15244.2.92.0/2244.2.92.1 to 44.2.95.25444.2.95.2551,022
15344.2.96.0/2244.2.96.1 to 44.2.99.25444.2.99.2551,022
15444.2.100.0/2244.2.100.1 to 44.2.103.25444.2.103.2551,022
15544.2.104.0/2244.2.104.1 to 44.2.107.25444.2.107.2551,022
15644.2.108.0/2244.2.108.1 to 44.2.111.25444.2.111.2551,022
15744.2.112.0/2244.2.112.1 to 44.2.115.25444.2.115.2551,022
15844.2.116.0/2244.2.116.1 to 44.2.119.25444.2.119.2551,022
15944.2.120.0/2244.2.120.1 to 44.2.123.25444.2.123.2551,022
16044.2.124.0/2244.2.124.1 to 44.2.127.25444.2.127.2551,022
16144.2.128.0/2244.2.128.1 to 44.2.131.25444.2.131.2551,022
16244.2.132.0/2244.2.132.1 to 44.2.135.25444.2.135.2551,022
16344.2.136.0/2244.2.136.1 to 44.2.139.25444.2.139.2551,022
16444.2.140.0/2244.2.140.1 to 44.2.143.25444.2.143.2551,022
16544.2.144.0/2244.2.144.1 to 44.2.147.25444.2.147.2551,022
16644.2.148.0/2244.2.148.1 to 44.2.151.25444.2.151.2551,022
16744.2.152.0/2244.2.152.1 to 44.2.155.25444.2.155.2551,022
16844.2.156.0/2244.2.156.1 to 44.2.159.25444.2.159.2551,022
16944.2.160.0/2244.2.160.1 to 44.2.163.25444.2.163.2551,022
17044.2.164.0/2244.2.164.1 to 44.2.167.25444.2.167.2551,022
17144.2.168.0/2244.2.168.1 to 44.2.171.25444.2.171.2551,022
17244.2.172.0/2244.2.172.1 to 44.2.175.25444.2.175.2551,022
17344.2.176.0/2244.2.176.1 to 44.2.179.25444.2.179.2551,022
17444.2.180.0/2244.2.180.1 to 44.2.183.25444.2.183.2551,022
17544.2.184.0/2244.2.184.1 to 44.2.187.25444.2.187.2551,022
17644.2.188.0/2244.2.188.1 to 44.2.191.25444.2.191.2551,022
17744.2.192.0/2244.2.192.1 to 44.2.195.25444.2.195.2551,022
17844.2.196.0/2244.2.196.1 to 44.2.199.25444.2.199.2551,022
17944.2.200.0/2244.2.200.1 to 44.2.203.25444.2.203.2551,022
18044.2.204.0/2244.2.204.1 to 44.2.207.25444.2.207.2551,022
18144.2.208.0/2244.2.208.1 to 44.2.211.25444.2.211.2551,022
18244.2.212.0/2244.2.212.1 to 44.2.215.25444.2.215.2551,022
18344.2.216.0/2244.2.216.1 to 44.2.219.25444.2.219.2551,022
18444.2.220.0/2244.2.220.1 to 44.2.223.25444.2.223.2551,022
18544.2.224.0/2244.2.224.1 to 44.2.227.25444.2.227.2551,022
18644.2.228.0/2244.2.228.1 to 44.2.231.25444.2.231.2551,022
18744.2.232.0/2244.2.232.1 to 44.2.235.25444.2.235.2551,022
18844.2.236.0/2244.2.236.1 to 44.2.239.25444.2.239.2551,022
18944.2.240.0/2244.2.240.1 to 44.2.243.25444.2.243.2551,022
19044.2.244.0/2244.2.244.1 to 44.2.247.25444.2.247.2551,022
19144.2.248.0/2244.2.248.1 to 44.2.251.25444.2.251.2551,022
19244.2.252.0/2244.2.252.1 to 44.2.255.25444.2.255.2551,022
19344.3.0.0/2244.3.0.1 to 44.3.3.25444.3.3.2551,022
19444.3.4.0/2244.3.4.1 to 44.3.7.25444.3.7.2551,022
19544.3.8.0/2244.3.8.1 to 44.3.11.25444.3.11.2551,022
19644.3.12.0/2244.3.12.1 to 44.3.15.25444.3.15.2551,022
19744.3.16.0/2244.3.16.1 to 44.3.19.25444.3.19.2551,022
19844.3.20.0/2244.3.20.1 to 44.3.23.25444.3.23.2551,022
19944.3.24.0/2244.3.24.1 to 44.3.27.25444.3.27.2551,022
20044.3.28.0/2244.3.28.1 to 44.3.31.25444.3.31.2551,022
20144.3.32.0/2244.3.32.1 to 44.3.35.25444.3.35.2551,022
20244.3.36.0/2244.3.36.1 to 44.3.39.25444.3.39.2551,022
20344.3.40.0/2244.3.40.1 to 44.3.43.25444.3.43.2551,022
20444.3.44.0/2244.3.44.1 to 44.3.47.25444.3.47.2551,022
20544.3.48.0/2244.3.48.1 to 44.3.51.25444.3.51.2551,022
20644.3.52.0/2244.3.52.1 to 44.3.55.25444.3.55.2551,022
20744.3.56.0/2244.3.56.1 to 44.3.59.25444.3.59.2551,022
20844.3.60.0/2244.3.60.1 to 44.3.63.25444.3.63.2551,022
20944.3.64.0/2244.3.64.1 to 44.3.67.25444.3.67.2551,022
21044.3.68.0/2244.3.68.1 to 44.3.71.25444.3.71.2551,022
21144.3.72.0/2244.3.72.1 to 44.3.75.25444.3.75.2551,022
21244.3.76.0/2244.3.76.1 to 44.3.79.25444.3.79.2551,022
21344.3.80.0/2244.3.80.1 to 44.3.83.25444.3.83.2551,022
21444.3.84.0/2244.3.84.1 to 44.3.87.25444.3.87.2551,022
21544.3.88.0/2244.3.88.1 to 44.3.91.25444.3.91.2551,022
21644.3.92.0/2244.3.92.1 to 44.3.95.25444.3.95.2551,022
21744.3.96.0/2244.3.96.1 to 44.3.99.25444.3.99.2551,022
21844.3.100.0/2244.3.100.1 to 44.3.103.25444.3.103.2551,022
21944.3.104.0/2244.3.104.1 to 44.3.107.25444.3.107.2551,022
22044.3.108.0/2244.3.108.1 to 44.3.111.25444.3.111.2551,022
22144.3.112.0/2244.3.112.1 to 44.3.115.25444.3.115.2551,022
22244.3.116.0/2244.3.116.1 to 44.3.119.25444.3.119.2551,022
22344.3.120.0/2244.3.120.1 to 44.3.123.25444.3.123.2551,022
22444.3.124.0/2244.3.124.1 to 44.3.127.25444.3.127.2551,022
22544.3.128.0/2244.3.128.1 to 44.3.131.25444.3.131.2551,022
22644.3.132.0/2244.3.132.1 to 44.3.135.25444.3.135.2551,022
22744.3.136.0/2244.3.136.1 to 44.3.139.25444.3.139.2551,022
22844.3.140.0/2244.3.140.1 to 44.3.143.25444.3.143.2551,022
22944.3.144.0/2244.3.144.1 to 44.3.147.25444.3.147.2551,022
23044.3.148.0/2244.3.148.1 to 44.3.151.25444.3.151.2551,022
23144.3.152.0/2244.3.152.1 to 44.3.155.25444.3.155.2551,022
23244.3.156.0/2244.3.156.1 to 44.3.159.25444.3.159.2551,022
23344.3.160.0/2244.3.160.1 to 44.3.163.25444.3.163.2551,022
23444.3.164.0/2244.3.164.1 to 44.3.167.25444.3.167.2551,022
23544.3.168.0/2244.3.168.1 to 44.3.171.25444.3.171.2551,022
23644.3.172.0/2244.3.172.1 to 44.3.175.25444.3.175.2551,022
23744.3.176.0/2244.3.176.1 to 44.3.179.25444.3.179.2551,022
23844.3.180.0/2244.3.180.1 to 44.3.183.25444.3.183.2551,022
23944.3.184.0/2244.3.184.1 to 44.3.187.25444.3.187.2551,022
24044.3.188.0/2244.3.188.1 to 44.3.191.25444.3.191.2551,022
24144.3.192.0/2244.3.192.1 to 44.3.195.25444.3.195.2551,022
24244.3.196.0/2244.3.196.1 to 44.3.199.25444.3.199.2551,022
24344.3.200.0/2244.3.200.1 to 44.3.203.25444.3.203.2551,022
24444.3.204.0/2244.3.204.1 to 44.3.207.25444.3.207.2551,022
24544.3.208.0/2244.3.208.1 to 44.3.211.25444.3.211.2551,022
24644.3.212.0/2244.3.212.1 to 44.3.215.25444.3.215.2551,022
24744.3.216.0/2244.3.216.1 to 44.3.219.25444.3.219.2551,022
24844.3.220.0/2244.3.220.1 to 44.3.223.25444.3.223.2551,022
24944.3.224.0/2244.3.224.1 to 44.3.227.25444.3.227.2551,022
25044.3.228.0/2244.3.228.1 to 44.3.231.25444.3.231.2551,022
25144.3.232.0/2244.3.232.1 to 44.3.235.25444.3.235.2551,022
25244.3.236.0/2244.3.236.1 to 44.3.239.25444.3.239.2551,022
25344.3.240.0/2244.3.240.1 to 44.3.243.25444.3.243.2551,022
25444.3.244.0/2244.3.244.1 to 44.3.247.25444.3.247.2551,022
25544.3.248.0/2244.3.248.1 to 44.3.251.25444.3.251.2551,022
25644.3.252.0/2244.3.252.1 to 44.3.255.25444.3.255.2551,022

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.