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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.

Network47.48.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
47.48.0.0
Broadcast address
47.48.255.255
First usable
47.48.0.1
Last usable
47.48.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 2F300000 · Integer 791674880 to 791740415
Reverse DNS zone
48.47.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101111.00110000..00000000.0000000047.48.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00101111.00110000..00000000.0000000047.48.0.0
Broadcast00101111.00110000..11111111.1111111147.48.255.255
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

47.48.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.48.0.0/2447.48.0.1 to 47.48.0.25447.48.0.255254
247.48.1.0/2447.48.1.1 to 47.48.1.25447.48.1.255254
347.48.2.0/2447.48.2.1 to 47.48.2.25447.48.2.255254
447.48.3.0/2447.48.3.1 to 47.48.3.25447.48.3.255254
547.48.4.0/2447.48.4.1 to 47.48.4.25447.48.4.255254
647.48.5.0/2447.48.5.1 to 47.48.5.25447.48.5.255254
747.48.6.0/2447.48.6.1 to 47.48.6.25447.48.6.255254
847.48.7.0/2447.48.7.1 to 47.48.7.25447.48.7.255254
947.48.8.0/2447.48.8.1 to 47.48.8.25447.48.8.255254
1047.48.9.0/2447.48.9.1 to 47.48.9.25447.48.9.255254
1147.48.10.0/2447.48.10.1 to 47.48.10.25447.48.10.255254
1247.48.11.0/2447.48.11.1 to 47.48.11.25447.48.11.255254
1347.48.12.0/2447.48.12.1 to 47.48.12.25447.48.12.255254
1447.48.13.0/2447.48.13.1 to 47.48.13.25447.48.13.255254
1547.48.14.0/2447.48.14.1 to 47.48.14.25447.48.14.255254
1647.48.15.0/2447.48.15.1 to 47.48.15.25447.48.15.255254
1747.48.16.0/2447.48.16.1 to 47.48.16.25447.48.16.255254
1847.48.17.0/2447.48.17.1 to 47.48.17.25447.48.17.255254
1947.48.18.0/2447.48.18.1 to 47.48.18.25447.48.18.255254
2047.48.19.0/2447.48.19.1 to 47.48.19.25447.48.19.255254
2147.48.20.0/2447.48.20.1 to 47.48.20.25447.48.20.255254
2247.48.21.0/2447.48.21.1 to 47.48.21.25447.48.21.255254
2347.48.22.0/2447.48.22.1 to 47.48.22.25447.48.22.255254
2447.48.23.0/2447.48.23.1 to 47.48.23.25447.48.23.255254
2547.48.24.0/2447.48.24.1 to 47.48.24.25447.48.24.255254
2647.48.25.0/2447.48.25.1 to 47.48.25.25447.48.25.255254
2747.48.26.0/2447.48.26.1 to 47.48.26.25447.48.26.255254
2847.48.27.0/2447.48.27.1 to 47.48.27.25447.48.27.255254
2947.48.28.0/2447.48.28.1 to 47.48.28.25447.48.28.255254
3047.48.29.0/2447.48.29.1 to 47.48.29.25447.48.29.255254
3147.48.30.0/2447.48.30.1 to 47.48.30.25447.48.30.255254
3247.48.31.0/2447.48.31.1 to 47.48.31.25447.48.31.255254
3347.48.32.0/2447.48.32.1 to 47.48.32.25447.48.32.255254
3447.48.33.0/2447.48.33.1 to 47.48.33.25447.48.33.255254
3547.48.34.0/2447.48.34.1 to 47.48.34.25447.48.34.255254
3647.48.35.0/2447.48.35.1 to 47.48.35.25447.48.35.255254
3747.48.36.0/2447.48.36.1 to 47.48.36.25447.48.36.255254
3847.48.37.0/2447.48.37.1 to 47.48.37.25447.48.37.255254
3947.48.38.0/2447.48.38.1 to 47.48.38.25447.48.38.255254
4047.48.39.0/2447.48.39.1 to 47.48.39.25447.48.39.255254
4147.48.40.0/2447.48.40.1 to 47.48.40.25447.48.40.255254
4247.48.41.0/2447.48.41.1 to 47.48.41.25447.48.41.255254
4347.48.42.0/2447.48.42.1 to 47.48.42.25447.48.42.255254
4447.48.43.0/2447.48.43.1 to 47.48.43.25447.48.43.255254
4547.48.44.0/2447.48.44.1 to 47.48.44.25447.48.44.255254
4647.48.45.0/2447.48.45.1 to 47.48.45.25447.48.45.255254
4747.48.46.0/2447.48.46.1 to 47.48.46.25447.48.46.255254
4847.48.47.0/2447.48.47.1 to 47.48.47.25447.48.47.255254
4947.48.48.0/2447.48.48.1 to 47.48.48.25447.48.48.255254
5047.48.49.0/2447.48.49.1 to 47.48.49.25447.48.49.255254
5147.48.50.0/2447.48.50.1 to 47.48.50.25447.48.50.255254
5247.48.51.0/2447.48.51.1 to 47.48.51.25447.48.51.255254
5347.48.52.0/2447.48.52.1 to 47.48.52.25447.48.52.255254
5447.48.53.0/2447.48.53.1 to 47.48.53.25447.48.53.255254
5547.48.54.0/2447.48.54.1 to 47.48.54.25447.48.54.255254
5647.48.55.0/2447.48.55.1 to 47.48.55.25447.48.55.255254
5747.48.56.0/2447.48.56.1 to 47.48.56.25447.48.56.255254
5847.48.57.0/2447.48.57.1 to 47.48.57.25447.48.57.255254
5947.48.58.0/2447.48.58.1 to 47.48.58.25447.48.58.255254
6047.48.59.0/2447.48.59.1 to 47.48.59.25447.48.59.255254
6147.48.60.0/2447.48.60.1 to 47.48.60.25447.48.60.255254
6247.48.61.0/2447.48.61.1 to 47.48.61.25447.48.61.255254
6347.48.62.0/2447.48.62.1 to 47.48.62.25447.48.62.255254
6447.48.63.0/2447.48.63.1 to 47.48.63.25447.48.63.255254
6547.48.64.0/2447.48.64.1 to 47.48.64.25447.48.64.255254
6647.48.65.0/2447.48.65.1 to 47.48.65.25447.48.65.255254
6747.48.66.0/2447.48.66.1 to 47.48.66.25447.48.66.255254
6847.48.67.0/2447.48.67.1 to 47.48.67.25447.48.67.255254
6947.48.68.0/2447.48.68.1 to 47.48.68.25447.48.68.255254
7047.48.69.0/2447.48.69.1 to 47.48.69.25447.48.69.255254
7147.48.70.0/2447.48.70.1 to 47.48.70.25447.48.70.255254
7247.48.71.0/2447.48.71.1 to 47.48.71.25447.48.71.255254
7347.48.72.0/2447.48.72.1 to 47.48.72.25447.48.72.255254
7447.48.73.0/2447.48.73.1 to 47.48.73.25447.48.73.255254
7547.48.74.0/2447.48.74.1 to 47.48.74.25447.48.74.255254
7647.48.75.0/2447.48.75.1 to 47.48.75.25447.48.75.255254
7747.48.76.0/2447.48.76.1 to 47.48.76.25447.48.76.255254
7847.48.77.0/2447.48.77.1 to 47.48.77.25447.48.77.255254
7947.48.78.0/2447.48.78.1 to 47.48.78.25447.48.78.255254
8047.48.79.0/2447.48.79.1 to 47.48.79.25447.48.79.255254
8147.48.80.0/2447.48.80.1 to 47.48.80.25447.48.80.255254
8247.48.81.0/2447.48.81.1 to 47.48.81.25447.48.81.255254
8347.48.82.0/2447.48.82.1 to 47.48.82.25447.48.82.255254
8447.48.83.0/2447.48.83.1 to 47.48.83.25447.48.83.255254
8547.48.84.0/2447.48.84.1 to 47.48.84.25447.48.84.255254
8647.48.85.0/2447.48.85.1 to 47.48.85.25447.48.85.255254
8747.48.86.0/2447.48.86.1 to 47.48.86.25447.48.86.255254
8847.48.87.0/2447.48.87.1 to 47.48.87.25447.48.87.255254
8947.48.88.0/2447.48.88.1 to 47.48.88.25447.48.88.255254
9047.48.89.0/2447.48.89.1 to 47.48.89.25447.48.89.255254
9147.48.90.0/2447.48.90.1 to 47.48.90.25447.48.90.255254
9247.48.91.0/2447.48.91.1 to 47.48.91.25447.48.91.255254
9347.48.92.0/2447.48.92.1 to 47.48.92.25447.48.92.255254
9447.48.93.0/2447.48.93.1 to 47.48.93.25447.48.93.255254
9547.48.94.0/2447.48.94.1 to 47.48.94.25447.48.94.255254
9647.48.95.0/2447.48.95.1 to 47.48.95.25447.48.95.255254
9747.48.96.0/2447.48.96.1 to 47.48.96.25447.48.96.255254
9847.48.97.0/2447.48.97.1 to 47.48.97.25447.48.97.255254
9947.48.98.0/2447.48.98.1 to 47.48.98.25447.48.98.255254
10047.48.99.0/2447.48.99.1 to 47.48.99.25447.48.99.255254
10147.48.100.0/2447.48.100.1 to 47.48.100.25447.48.100.255254
10247.48.101.0/2447.48.101.1 to 47.48.101.25447.48.101.255254
10347.48.102.0/2447.48.102.1 to 47.48.102.25447.48.102.255254
10447.48.103.0/2447.48.103.1 to 47.48.103.25447.48.103.255254
10547.48.104.0/2447.48.104.1 to 47.48.104.25447.48.104.255254
10647.48.105.0/2447.48.105.1 to 47.48.105.25447.48.105.255254
10747.48.106.0/2447.48.106.1 to 47.48.106.25447.48.106.255254
10847.48.107.0/2447.48.107.1 to 47.48.107.25447.48.107.255254
10947.48.108.0/2447.48.108.1 to 47.48.108.25447.48.108.255254
11047.48.109.0/2447.48.109.1 to 47.48.109.25447.48.109.255254
11147.48.110.0/2447.48.110.1 to 47.48.110.25447.48.110.255254
11247.48.111.0/2447.48.111.1 to 47.48.111.25447.48.111.255254
11347.48.112.0/2447.48.112.1 to 47.48.112.25447.48.112.255254
11447.48.113.0/2447.48.113.1 to 47.48.113.25447.48.113.255254
11547.48.114.0/2447.48.114.1 to 47.48.114.25447.48.114.255254
11647.48.115.0/2447.48.115.1 to 47.48.115.25447.48.115.255254
11747.48.116.0/2447.48.116.1 to 47.48.116.25447.48.116.255254
11847.48.117.0/2447.48.117.1 to 47.48.117.25447.48.117.255254
11947.48.118.0/2447.48.118.1 to 47.48.118.25447.48.118.255254
12047.48.119.0/2447.48.119.1 to 47.48.119.25447.48.119.255254
12147.48.120.0/2447.48.120.1 to 47.48.120.25447.48.120.255254
12247.48.121.0/2447.48.121.1 to 47.48.121.25447.48.121.255254
12347.48.122.0/2447.48.122.1 to 47.48.122.25447.48.122.255254
12447.48.123.0/2447.48.123.1 to 47.48.123.25447.48.123.255254
12547.48.124.0/2447.48.124.1 to 47.48.124.25447.48.124.255254
12647.48.125.0/2447.48.125.1 to 47.48.125.25447.48.125.255254
12747.48.126.0/2447.48.126.1 to 47.48.126.25447.48.126.255254
12847.48.127.0/2447.48.127.1 to 47.48.127.25447.48.127.255254
12947.48.128.0/2447.48.128.1 to 47.48.128.25447.48.128.255254
13047.48.129.0/2447.48.129.1 to 47.48.129.25447.48.129.255254
13147.48.130.0/2447.48.130.1 to 47.48.130.25447.48.130.255254
13247.48.131.0/2447.48.131.1 to 47.48.131.25447.48.131.255254
13347.48.132.0/2447.48.132.1 to 47.48.132.25447.48.132.255254
13447.48.133.0/2447.48.133.1 to 47.48.133.25447.48.133.255254
13547.48.134.0/2447.48.134.1 to 47.48.134.25447.48.134.255254
13647.48.135.0/2447.48.135.1 to 47.48.135.25447.48.135.255254
13747.48.136.0/2447.48.136.1 to 47.48.136.25447.48.136.255254
13847.48.137.0/2447.48.137.1 to 47.48.137.25447.48.137.255254
13947.48.138.0/2447.48.138.1 to 47.48.138.25447.48.138.255254
14047.48.139.0/2447.48.139.1 to 47.48.139.25447.48.139.255254
14147.48.140.0/2447.48.140.1 to 47.48.140.25447.48.140.255254
14247.48.141.0/2447.48.141.1 to 47.48.141.25447.48.141.255254
14347.48.142.0/2447.48.142.1 to 47.48.142.25447.48.142.255254
14447.48.143.0/2447.48.143.1 to 47.48.143.25447.48.143.255254
14547.48.144.0/2447.48.144.1 to 47.48.144.25447.48.144.255254
14647.48.145.0/2447.48.145.1 to 47.48.145.25447.48.145.255254
14747.48.146.0/2447.48.146.1 to 47.48.146.25447.48.146.255254
14847.48.147.0/2447.48.147.1 to 47.48.147.25447.48.147.255254
14947.48.148.0/2447.48.148.1 to 47.48.148.25447.48.148.255254
15047.48.149.0/2447.48.149.1 to 47.48.149.25447.48.149.255254
15147.48.150.0/2447.48.150.1 to 47.48.150.25447.48.150.255254
15247.48.151.0/2447.48.151.1 to 47.48.151.25447.48.151.255254
15347.48.152.0/2447.48.152.1 to 47.48.152.25447.48.152.255254
15447.48.153.0/2447.48.153.1 to 47.48.153.25447.48.153.255254
15547.48.154.0/2447.48.154.1 to 47.48.154.25447.48.154.255254
15647.48.155.0/2447.48.155.1 to 47.48.155.25447.48.155.255254
15747.48.156.0/2447.48.156.1 to 47.48.156.25447.48.156.255254
15847.48.157.0/2447.48.157.1 to 47.48.157.25447.48.157.255254
15947.48.158.0/2447.48.158.1 to 47.48.158.25447.48.158.255254
16047.48.159.0/2447.48.159.1 to 47.48.159.25447.48.159.255254
16147.48.160.0/2447.48.160.1 to 47.48.160.25447.48.160.255254
16247.48.161.0/2447.48.161.1 to 47.48.161.25447.48.161.255254
16347.48.162.0/2447.48.162.1 to 47.48.162.25447.48.162.255254
16447.48.163.0/2447.48.163.1 to 47.48.163.25447.48.163.255254
16547.48.164.0/2447.48.164.1 to 47.48.164.25447.48.164.255254
16647.48.165.0/2447.48.165.1 to 47.48.165.25447.48.165.255254
16747.48.166.0/2447.48.166.1 to 47.48.166.25447.48.166.255254
16847.48.167.0/2447.48.167.1 to 47.48.167.25447.48.167.255254
16947.48.168.0/2447.48.168.1 to 47.48.168.25447.48.168.255254
17047.48.169.0/2447.48.169.1 to 47.48.169.25447.48.169.255254
17147.48.170.0/2447.48.170.1 to 47.48.170.25447.48.170.255254
17247.48.171.0/2447.48.171.1 to 47.48.171.25447.48.171.255254
17347.48.172.0/2447.48.172.1 to 47.48.172.25447.48.172.255254
17447.48.173.0/2447.48.173.1 to 47.48.173.25447.48.173.255254
17547.48.174.0/2447.48.174.1 to 47.48.174.25447.48.174.255254
17647.48.175.0/2447.48.175.1 to 47.48.175.25447.48.175.255254
17747.48.176.0/2447.48.176.1 to 47.48.176.25447.48.176.255254
17847.48.177.0/2447.48.177.1 to 47.48.177.25447.48.177.255254
17947.48.178.0/2447.48.178.1 to 47.48.178.25447.48.178.255254
18047.48.179.0/2447.48.179.1 to 47.48.179.25447.48.179.255254
18147.48.180.0/2447.48.180.1 to 47.48.180.25447.48.180.255254
18247.48.181.0/2447.48.181.1 to 47.48.181.25447.48.181.255254
18347.48.182.0/2447.48.182.1 to 47.48.182.25447.48.182.255254
18447.48.183.0/2447.48.183.1 to 47.48.183.25447.48.183.255254
18547.48.184.0/2447.48.184.1 to 47.48.184.25447.48.184.255254
18647.48.185.0/2447.48.185.1 to 47.48.185.25447.48.185.255254
18747.48.186.0/2447.48.186.1 to 47.48.186.25447.48.186.255254
18847.48.187.0/2447.48.187.1 to 47.48.187.25447.48.187.255254
18947.48.188.0/2447.48.188.1 to 47.48.188.25447.48.188.255254
19047.48.189.0/2447.48.189.1 to 47.48.189.25447.48.189.255254
19147.48.190.0/2447.48.190.1 to 47.48.190.25447.48.190.255254
19247.48.191.0/2447.48.191.1 to 47.48.191.25447.48.191.255254
19347.48.192.0/2447.48.192.1 to 47.48.192.25447.48.192.255254
19447.48.193.0/2447.48.193.1 to 47.48.193.25447.48.193.255254
19547.48.194.0/2447.48.194.1 to 47.48.194.25447.48.194.255254
19647.48.195.0/2447.48.195.1 to 47.48.195.25447.48.195.255254
19747.48.196.0/2447.48.196.1 to 47.48.196.25447.48.196.255254
19847.48.197.0/2447.48.197.1 to 47.48.197.25447.48.197.255254
19947.48.198.0/2447.48.198.1 to 47.48.198.25447.48.198.255254
20047.48.199.0/2447.48.199.1 to 47.48.199.25447.48.199.255254
20147.48.200.0/2447.48.200.1 to 47.48.200.25447.48.200.255254
20247.48.201.0/2447.48.201.1 to 47.48.201.25447.48.201.255254
20347.48.202.0/2447.48.202.1 to 47.48.202.25447.48.202.255254
20447.48.203.0/2447.48.203.1 to 47.48.203.25447.48.203.255254
20547.48.204.0/2447.48.204.1 to 47.48.204.25447.48.204.255254
20647.48.205.0/2447.48.205.1 to 47.48.205.25447.48.205.255254
20747.48.206.0/2447.48.206.1 to 47.48.206.25447.48.206.255254
20847.48.207.0/2447.48.207.1 to 47.48.207.25447.48.207.255254
20947.48.208.0/2447.48.208.1 to 47.48.208.25447.48.208.255254
21047.48.209.0/2447.48.209.1 to 47.48.209.25447.48.209.255254
21147.48.210.0/2447.48.210.1 to 47.48.210.25447.48.210.255254
21247.48.211.0/2447.48.211.1 to 47.48.211.25447.48.211.255254
21347.48.212.0/2447.48.212.1 to 47.48.212.25447.48.212.255254
21447.48.213.0/2447.48.213.1 to 47.48.213.25447.48.213.255254
21547.48.214.0/2447.48.214.1 to 47.48.214.25447.48.214.255254
21647.48.215.0/2447.48.215.1 to 47.48.215.25447.48.215.255254
21747.48.216.0/2447.48.216.1 to 47.48.216.25447.48.216.255254
21847.48.217.0/2447.48.217.1 to 47.48.217.25447.48.217.255254
21947.48.218.0/2447.48.218.1 to 47.48.218.25447.48.218.255254
22047.48.219.0/2447.48.219.1 to 47.48.219.25447.48.219.255254
22147.48.220.0/2447.48.220.1 to 47.48.220.25447.48.220.255254
22247.48.221.0/2447.48.221.1 to 47.48.221.25447.48.221.255254
22347.48.222.0/2447.48.222.1 to 47.48.222.25447.48.222.255254
22447.48.223.0/2447.48.223.1 to 47.48.223.25447.48.223.255254
22547.48.224.0/2447.48.224.1 to 47.48.224.25447.48.224.255254
22647.48.225.0/2447.48.225.1 to 47.48.225.25447.48.225.255254
22747.48.226.0/2447.48.226.1 to 47.48.226.25447.48.226.255254
22847.48.227.0/2447.48.227.1 to 47.48.227.25447.48.227.255254
22947.48.228.0/2447.48.228.1 to 47.48.228.25447.48.228.255254
23047.48.229.0/2447.48.229.1 to 47.48.229.25447.48.229.255254
23147.48.230.0/2447.48.230.1 to 47.48.230.25447.48.230.255254
23247.48.231.0/2447.48.231.1 to 47.48.231.25447.48.231.255254
23347.48.232.0/2447.48.232.1 to 47.48.232.25447.48.232.255254
23447.48.233.0/2447.48.233.1 to 47.48.233.25447.48.233.255254
23547.48.234.0/2447.48.234.1 to 47.48.234.25447.48.234.255254
23647.48.235.0/2447.48.235.1 to 47.48.235.25447.48.235.255254
23747.48.236.0/2447.48.236.1 to 47.48.236.25447.48.236.255254
23847.48.237.0/2447.48.237.1 to 47.48.237.25447.48.237.255254
23947.48.238.0/2447.48.238.1 to 47.48.238.25447.48.238.255254
24047.48.239.0/2447.48.239.1 to 47.48.239.25447.48.239.255254
24147.48.240.0/2447.48.240.1 to 47.48.240.25447.48.240.255254
24247.48.241.0/2447.48.241.1 to 47.48.241.25447.48.241.255254
24347.48.242.0/2447.48.242.1 to 47.48.242.25447.48.242.255254
24447.48.243.0/2447.48.243.1 to 47.48.243.25447.48.243.255254
24547.48.244.0/2447.48.244.1 to 47.48.244.25447.48.244.255254
24647.48.245.0/2447.48.245.1 to 47.48.245.25447.48.245.255254
24747.48.246.0/2447.48.246.1 to 47.48.246.25447.48.246.255254
24847.48.247.0/2447.48.247.1 to 47.48.247.25447.48.247.255254
24947.48.248.0/2447.48.248.1 to 47.48.248.25447.48.248.255254
25047.48.249.0/2447.48.249.1 to 47.48.249.25447.48.249.255254
25147.48.250.0/2447.48.250.1 to 47.48.250.25447.48.250.255254
25247.48.251.0/2447.48.251.1 to 47.48.251.25447.48.251.255254
25347.48.252.0/2447.48.252.1 to 47.48.252.25447.48.252.255254
25447.48.253.0/2447.48.253.1 to 47.48.253.25447.48.253.255254
25547.48.254.0/2447.48.254.1 to 47.48.254.25447.48.254.255254
25647.48.255.0/2447.48.255.1 to 47.48.255.25447.48.255.255254

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.