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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.

Network41.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
41.167.0.0
Broadcast address
41.167.255.255
First usable
41.167.0.1
Last usable
41.167.255.254
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 29A70000 · Integer 698810368 to 698875903
Reverse DNS zone
167.41.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101001.10100111..00000000.0000000041.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00101001.10100111..00000000.0000000041.167.0.0
Broadcast00101001.10100111..11111111.1111111141.167.255.255
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)

41.167.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
141.167.0.0/2441.167.0.1 to 41.167.0.25441.167.0.255254
241.167.1.0/2441.167.1.1 to 41.167.1.25441.167.1.255254
341.167.2.0/2441.167.2.1 to 41.167.2.25441.167.2.255254
441.167.3.0/2441.167.3.1 to 41.167.3.25441.167.3.255254
541.167.4.0/2441.167.4.1 to 41.167.4.25441.167.4.255254
641.167.5.0/2441.167.5.1 to 41.167.5.25441.167.5.255254
741.167.6.0/2441.167.6.1 to 41.167.6.25441.167.6.255254
841.167.7.0/2441.167.7.1 to 41.167.7.25441.167.7.255254
941.167.8.0/2441.167.8.1 to 41.167.8.25441.167.8.255254
1041.167.9.0/2441.167.9.1 to 41.167.9.25441.167.9.255254
1141.167.10.0/2441.167.10.1 to 41.167.10.25441.167.10.255254
1241.167.11.0/2441.167.11.1 to 41.167.11.25441.167.11.255254
1341.167.12.0/2441.167.12.1 to 41.167.12.25441.167.12.255254
1441.167.13.0/2441.167.13.1 to 41.167.13.25441.167.13.255254
1541.167.14.0/2441.167.14.1 to 41.167.14.25441.167.14.255254
1641.167.15.0/2441.167.15.1 to 41.167.15.25441.167.15.255254
1741.167.16.0/2441.167.16.1 to 41.167.16.25441.167.16.255254
1841.167.17.0/2441.167.17.1 to 41.167.17.25441.167.17.255254
1941.167.18.0/2441.167.18.1 to 41.167.18.25441.167.18.255254
2041.167.19.0/2441.167.19.1 to 41.167.19.25441.167.19.255254
2141.167.20.0/2441.167.20.1 to 41.167.20.25441.167.20.255254
2241.167.21.0/2441.167.21.1 to 41.167.21.25441.167.21.255254
2341.167.22.0/2441.167.22.1 to 41.167.22.25441.167.22.255254
2441.167.23.0/2441.167.23.1 to 41.167.23.25441.167.23.255254
2541.167.24.0/2441.167.24.1 to 41.167.24.25441.167.24.255254
2641.167.25.0/2441.167.25.1 to 41.167.25.25441.167.25.255254
2741.167.26.0/2441.167.26.1 to 41.167.26.25441.167.26.255254
2841.167.27.0/2441.167.27.1 to 41.167.27.25441.167.27.255254
2941.167.28.0/2441.167.28.1 to 41.167.28.25441.167.28.255254
3041.167.29.0/2441.167.29.1 to 41.167.29.25441.167.29.255254
3141.167.30.0/2441.167.30.1 to 41.167.30.25441.167.30.255254
3241.167.31.0/2441.167.31.1 to 41.167.31.25441.167.31.255254
3341.167.32.0/2441.167.32.1 to 41.167.32.25441.167.32.255254
3441.167.33.0/2441.167.33.1 to 41.167.33.25441.167.33.255254
3541.167.34.0/2441.167.34.1 to 41.167.34.25441.167.34.255254
3641.167.35.0/2441.167.35.1 to 41.167.35.25441.167.35.255254
3741.167.36.0/2441.167.36.1 to 41.167.36.25441.167.36.255254
3841.167.37.0/2441.167.37.1 to 41.167.37.25441.167.37.255254
3941.167.38.0/2441.167.38.1 to 41.167.38.25441.167.38.255254
4041.167.39.0/2441.167.39.1 to 41.167.39.25441.167.39.255254
4141.167.40.0/2441.167.40.1 to 41.167.40.25441.167.40.255254
4241.167.41.0/2441.167.41.1 to 41.167.41.25441.167.41.255254
4341.167.42.0/2441.167.42.1 to 41.167.42.25441.167.42.255254
4441.167.43.0/2441.167.43.1 to 41.167.43.25441.167.43.255254
4541.167.44.0/2441.167.44.1 to 41.167.44.25441.167.44.255254
4641.167.45.0/2441.167.45.1 to 41.167.45.25441.167.45.255254
4741.167.46.0/2441.167.46.1 to 41.167.46.25441.167.46.255254
4841.167.47.0/2441.167.47.1 to 41.167.47.25441.167.47.255254
4941.167.48.0/2441.167.48.1 to 41.167.48.25441.167.48.255254
5041.167.49.0/2441.167.49.1 to 41.167.49.25441.167.49.255254
5141.167.50.0/2441.167.50.1 to 41.167.50.25441.167.50.255254
5241.167.51.0/2441.167.51.1 to 41.167.51.25441.167.51.255254
5341.167.52.0/2441.167.52.1 to 41.167.52.25441.167.52.255254
5441.167.53.0/2441.167.53.1 to 41.167.53.25441.167.53.255254
5541.167.54.0/2441.167.54.1 to 41.167.54.25441.167.54.255254
5641.167.55.0/2441.167.55.1 to 41.167.55.25441.167.55.255254
5741.167.56.0/2441.167.56.1 to 41.167.56.25441.167.56.255254
5841.167.57.0/2441.167.57.1 to 41.167.57.25441.167.57.255254
5941.167.58.0/2441.167.58.1 to 41.167.58.25441.167.58.255254
6041.167.59.0/2441.167.59.1 to 41.167.59.25441.167.59.255254
6141.167.60.0/2441.167.60.1 to 41.167.60.25441.167.60.255254
6241.167.61.0/2441.167.61.1 to 41.167.61.25441.167.61.255254
6341.167.62.0/2441.167.62.1 to 41.167.62.25441.167.62.255254
6441.167.63.0/2441.167.63.1 to 41.167.63.25441.167.63.255254
6541.167.64.0/2441.167.64.1 to 41.167.64.25441.167.64.255254
6641.167.65.0/2441.167.65.1 to 41.167.65.25441.167.65.255254
6741.167.66.0/2441.167.66.1 to 41.167.66.25441.167.66.255254
6841.167.67.0/2441.167.67.1 to 41.167.67.25441.167.67.255254
6941.167.68.0/2441.167.68.1 to 41.167.68.25441.167.68.255254
7041.167.69.0/2441.167.69.1 to 41.167.69.25441.167.69.255254
7141.167.70.0/2441.167.70.1 to 41.167.70.25441.167.70.255254
7241.167.71.0/2441.167.71.1 to 41.167.71.25441.167.71.255254
7341.167.72.0/2441.167.72.1 to 41.167.72.25441.167.72.255254
7441.167.73.0/2441.167.73.1 to 41.167.73.25441.167.73.255254
7541.167.74.0/2441.167.74.1 to 41.167.74.25441.167.74.255254
7641.167.75.0/2441.167.75.1 to 41.167.75.25441.167.75.255254
7741.167.76.0/2441.167.76.1 to 41.167.76.25441.167.76.255254
7841.167.77.0/2441.167.77.1 to 41.167.77.25441.167.77.255254
7941.167.78.0/2441.167.78.1 to 41.167.78.25441.167.78.255254
8041.167.79.0/2441.167.79.1 to 41.167.79.25441.167.79.255254
8141.167.80.0/2441.167.80.1 to 41.167.80.25441.167.80.255254
8241.167.81.0/2441.167.81.1 to 41.167.81.25441.167.81.255254
8341.167.82.0/2441.167.82.1 to 41.167.82.25441.167.82.255254
8441.167.83.0/2441.167.83.1 to 41.167.83.25441.167.83.255254
8541.167.84.0/2441.167.84.1 to 41.167.84.25441.167.84.255254
8641.167.85.0/2441.167.85.1 to 41.167.85.25441.167.85.255254
8741.167.86.0/2441.167.86.1 to 41.167.86.25441.167.86.255254
8841.167.87.0/2441.167.87.1 to 41.167.87.25441.167.87.255254
8941.167.88.0/2441.167.88.1 to 41.167.88.25441.167.88.255254
9041.167.89.0/2441.167.89.1 to 41.167.89.25441.167.89.255254
9141.167.90.0/2441.167.90.1 to 41.167.90.25441.167.90.255254
9241.167.91.0/2441.167.91.1 to 41.167.91.25441.167.91.255254
9341.167.92.0/2441.167.92.1 to 41.167.92.25441.167.92.255254
9441.167.93.0/2441.167.93.1 to 41.167.93.25441.167.93.255254
9541.167.94.0/2441.167.94.1 to 41.167.94.25441.167.94.255254
9641.167.95.0/2441.167.95.1 to 41.167.95.25441.167.95.255254
9741.167.96.0/2441.167.96.1 to 41.167.96.25441.167.96.255254
9841.167.97.0/2441.167.97.1 to 41.167.97.25441.167.97.255254
9941.167.98.0/2441.167.98.1 to 41.167.98.25441.167.98.255254
10041.167.99.0/2441.167.99.1 to 41.167.99.25441.167.99.255254
10141.167.100.0/2441.167.100.1 to 41.167.100.25441.167.100.255254
10241.167.101.0/2441.167.101.1 to 41.167.101.25441.167.101.255254
10341.167.102.0/2441.167.102.1 to 41.167.102.25441.167.102.255254
10441.167.103.0/2441.167.103.1 to 41.167.103.25441.167.103.255254
10541.167.104.0/2441.167.104.1 to 41.167.104.25441.167.104.255254
10641.167.105.0/2441.167.105.1 to 41.167.105.25441.167.105.255254
10741.167.106.0/2441.167.106.1 to 41.167.106.25441.167.106.255254
10841.167.107.0/2441.167.107.1 to 41.167.107.25441.167.107.255254
10941.167.108.0/2441.167.108.1 to 41.167.108.25441.167.108.255254
11041.167.109.0/2441.167.109.1 to 41.167.109.25441.167.109.255254
11141.167.110.0/2441.167.110.1 to 41.167.110.25441.167.110.255254
11241.167.111.0/2441.167.111.1 to 41.167.111.25441.167.111.255254
11341.167.112.0/2441.167.112.1 to 41.167.112.25441.167.112.255254
11441.167.113.0/2441.167.113.1 to 41.167.113.25441.167.113.255254
11541.167.114.0/2441.167.114.1 to 41.167.114.25441.167.114.255254
11641.167.115.0/2441.167.115.1 to 41.167.115.25441.167.115.255254
11741.167.116.0/2441.167.116.1 to 41.167.116.25441.167.116.255254
11841.167.117.0/2441.167.117.1 to 41.167.117.25441.167.117.255254
11941.167.118.0/2441.167.118.1 to 41.167.118.25441.167.118.255254
12041.167.119.0/2441.167.119.1 to 41.167.119.25441.167.119.255254
12141.167.120.0/2441.167.120.1 to 41.167.120.25441.167.120.255254
12241.167.121.0/2441.167.121.1 to 41.167.121.25441.167.121.255254
12341.167.122.0/2441.167.122.1 to 41.167.122.25441.167.122.255254
12441.167.123.0/2441.167.123.1 to 41.167.123.25441.167.123.255254
12541.167.124.0/2441.167.124.1 to 41.167.124.25441.167.124.255254
12641.167.125.0/2441.167.125.1 to 41.167.125.25441.167.125.255254
12741.167.126.0/2441.167.126.1 to 41.167.126.25441.167.126.255254
12841.167.127.0/2441.167.127.1 to 41.167.127.25441.167.127.255254
12941.167.128.0/2441.167.128.1 to 41.167.128.25441.167.128.255254
13041.167.129.0/2441.167.129.1 to 41.167.129.25441.167.129.255254
13141.167.130.0/2441.167.130.1 to 41.167.130.25441.167.130.255254
13241.167.131.0/2441.167.131.1 to 41.167.131.25441.167.131.255254
13341.167.132.0/2441.167.132.1 to 41.167.132.25441.167.132.255254
13441.167.133.0/2441.167.133.1 to 41.167.133.25441.167.133.255254
13541.167.134.0/2441.167.134.1 to 41.167.134.25441.167.134.255254
13641.167.135.0/2441.167.135.1 to 41.167.135.25441.167.135.255254
13741.167.136.0/2441.167.136.1 to 41.167.136.25441.167.136.255254
13841.167.137.0/2441.167.137.1 to 41.167.137.25441.167.137.255254
13941.167.138.0/2441.167.138.1 to 41.167.138.25441.167.138.255254
14041.167.139.0/2441.167.139.1 to 41.167.139.25441.167.139.255254
14141.167.140.0/2441.167.140.1 to 41.167.140.25441.167.140.255254
14241.167.141.0/2441.167.141.1 to 41.167.141.25441.167.141.255254
14341.167.142.0/2441.167.142.1 to 41.167.142.25441.167.142.255254
14441.167.143.0/2441.167.143.1 to 41.167.143.25441.167.143.255254
14541.167.144.0/2441.167.144.1 to 41.167.144.25441.167.144.255254
14641.167.145.0/2441.167.145.1 to 41.167.145.25441.167.145.255254
14741.167.146.0/2441.167.146.1 to 41.167.146.25441.167.146.255254
14841.167.147.0/2441.167.147.1 to 41.167.147.25441.167.147.255254
14941.167.148.0/2441.167.148.1 to 41.167.148.25441.167.148.255254
15041.167.149.0/2441.167.149.1 to 41.167.149.25441.167.149.255254
15141.167.150.0/2441.167.150.1 to 41.167.150.25441.167.150.255254
15241.167.151.0/2441.167.151.1 to 41.167.151.25441.167.151.255254
15341.167.152.0/2441.167.152.1 to 41.167.152.25441.167.152.255254
15441.167.153.0/2441.167.153.1 to 41.167.153.25441.167.153.255254
15541.167.154.0/2441.167.154.1 to 41.167.154.25441.167.154.255254
15641.167.155.0/2441.167.155.1 to 41.167.155.25441.167.155.255254
15741.167.156.0/2441.167.156.1 to 41.167.156.25441.167.156.255254
15841.167.157.0/2441.167.157.1 to 41.167.157.25441.167.157.255254
15941.167.158.0/2441.167.158.1 to 41.167.158.25441.167.158.255254
16041.167.159.0/2441.167.159.1 to 41.167.159.25441.167.159.255254
16141.167.160.0/2441.167.160.1 to 41.167.160.25441.167.160.255254
16241.167.161.0/2441.167.161.1 to 41.167.161.25441.167.161.255254
16341.167.162.0/2441.167.162.1 to 41.167.162.25441.167.162.255254
16441.167.163.0/2441.167.163.1 to 41.167.163.25441.167.163.255254
16541.167.164.0/2441.167.164.1 to 41.167.164.25441.167.164.255254
16641.167.165.0/2441.167.165.1 to 41.167.165.25441.167.165.255254
16741.167.166.0/2441.167.166.1 to 41.167.166.25441.167.166.255254
16841.167.167.0/2441.167.167.1 to 41.167.167.25441.167.167.255254
16941.167.168.0/2441.167.168.1 to 41.167.168.25441.167.168.255254
17041.167.169.0/2441.167.169.1 to 41.167.169.25441.167.169.255254
17141.167.170.0/2441.167.170.1 to 41.167.170.25441.167.170.255254
17241.167.171.0/2441.167.171.1 to 41.167.171.25441.167.171.255254
17341.167.172.0/2441.167.172.1 to 41.167.172.25441.167.172.255254
17441.167.173.0/2441.167.173.1 to 41.167.173.25441.167.173.255254
17541.167.174.0/2441.167.174.1 to 41.167.174.25441.167.174.255254
17641.167.175.0/2441.167.175.1 to 41.167.175.25441.167.175.255254
17741.167.176.0/2441.167.176.1 to 41.167.176.25441.167.176.255254
17841.167.177.0/2441.167.177.1 to 41.167.177.25441.167.177.255254
17941.167.178.0/2441.167.178.1 to 41.167.178.25441.167.178.255254
18041.167.179.0/2441.167.179.1 to 41.167.179.25441.167.179.255254
18141.167.180.0/2441.167.180.1 to 41.167.180.25441.167.180.255254
18241.167.181.0/2441.167.181.1 to 41.167.181.25441.167.181.255254
18341.167.182.0/2441.167.182.1 to 41.167.182.25441.167.182.255254
18441.167.183.0/2441.167.183.1 to 41.167.183.25441.167.183.255254
18541.167.184.0/2441.167.184.1 to 41.167.184.25441.167.184.255254
18641.167.185.0/2441.167.185.1 to 41.167.185.25441.167.185.255254
18741.167.186.0/2441.167.186.1 to 41.167.186.25441.167.186.255254
18841.167.187.0/2441.167.187.1 to 41.167.187.25441.167.187.255254
18941.167.188.0/2441.167.188.1 to 41.167.188.25441.167.188.255254
19041.167.189.0/2441.167.189.1 to 41.167.189.25441.167.189.255254
19141.167.190.0/2441.167.190.1 to 41.167.190.25441.167.190.255254
19241.167.191.0/2441.167.191.1 to 41.167.191.25441.167.191.255254
19341.167.192.0/2441.167.192.1 to 41.167.192.25441.167.192.255254
19441.167.193.0/2441.167.193.1 to 41.167.193.25441.167.193.255254
19541.167.194.0/2441.167.194.1 to 41.167.194.25441.167.194.255254
19641.167.195.0/2441.167.195.1 to 41.167.195.25441.167.195.255254
19741.167.196.0/2441.167.196.1 to 41.167.196.25441.167.196.255254
19841.167.197.0/2441.167.197.1 to 41.167.197.25441.167.197.255254
19941.167.198.0/2441.167.198.1 to 41.167.198.25441.167.198.255254
20041.167.199.0/2441.167.199.1 to 41.167.199.25441.167.199.255254
20141.167.200.0/2441.167.200.1 to 41.167.200.25441.167.200.255254
20241.167.201.0/2441.167.201.1 to 41.167.201.25441.167.201.255254
20341.167.202.0/2441.167.202.1 to 41.167.202.25441.167.202.255254
20441.167.203.0/2441.167.203.1 to 41.167.203.25441.167.203.255254
20541.167.204.0/2441.167.204.1 to 41.167.204.25441.167.204.255254
20641.167.205.0/2441.167.205.1 to 41.167.205.25441.167.205.255254
20741.167.206.0/2441.167.206.1 to 41.167.206.25441.167.206.255254
20841.167.207.0/2441.167.207.1 to 41.167.207.25441.167.207.255254
20941.167.208.0/2441.167.208.1 to 41.167.208.25441.167.208.255254
21041.167.209.0/2441.167.209.1 to 41.167.209.25441.167.209.255254
21141.167.210.0/2441.167.210.1 to 41.167.210.25441.167.210.255254
21241.167.211.0/2441.167.211.1 to 41.167.211.25441.167.211.255254
21341.167.212.0/2441.167.212.1 to 41.167.212.25441.167.212.255254
21441.167.213.0/2441.167.213.1 to 41.167.213.25441.167.213.255254
21541.167.214.0/2441.167.214.1 to 41.167.214.25441.167.214.255254
21641.167.215.0/2441.167.215.1 to 41.167.215.25441.167.215.255254
21741.167.216.0/2441.167.216.1 to 41.167.216.25441.167.216.255254
21841.167.217.0/2441.167.217.1 to 41.167.217.25441.167.217.255254
21941.167.218.0/2441.167.218.1 to 41.167.218.25441.167.218.255254
22041.167.219.0/2441.167.219.1 to 41.167.219.25441.167.219.255254
22141.167.220.0/2441.167.220.1 to 41.167.220.25441.167.220.255254
22241.167.221.0/2441.167.221.1 to 41.167.221.25441.167.221.255254
22341.167.222.0/2441.167.222.1 to 41.167.222.25441.167.222.255254
22441.167.223.0/2441.167.223.1 to 41.167.223.25441.167.223.255254
22541.167.224.0/2441.167.224.1 to 41.167.224.25441.167.224.255254
22641.167.225.0/2441.167.225.1 to 41.167.225.25441.167.225.255254
22741.167.226.0/2441.167.226.1 to 41.167.226.25441.167.226.255254
22841.167.227.0/2441.167.227.1 to 41.167.227.25441.167.227.255254
22941.167.228.0/2441.167.228.1 to 41.167.228.25441.167.228.255254
23041.167.229.0/2441.167.229.1 to 41.167.229.25441.167.229.255254
23141.167.230.0/2441.167.230.1 to 41.167.230.25441.167.230.255254
23241.167.231.0/2441.167.231.1 to 41.167.231.25441.167.231.255254
23341.167.232.0/2441.167.232.1 to 41.167.232.25441.167.232.255254
23441.167.233.0/2441.167.233.1 to 41.167.233.25441.167.233.255254
23541.167.234.0/2441.167.234.1 to 41.167.234.25441.167.234.255254
23641.167.235.0/2441.167.235.1 to 41.167.235.25441.167.235.255254
23741.167.236.0/2441.167.236.1 to 41.167.236.25441.167.236.255254
23841.167.237.0/2441.167.237.1 to 41.167.237.25441.167.237.255254
23941.167.238.0/2441.167.238.1 to 41.167.238.25441.167.238.255254
24041.167.239.0/2441.167.239.1 to 41.167.239.25441.167.239.255254
24141.167.240.0/2441.167.240.1 to 41.167.240.25441.167.240.255254
24241.167.241.0/2441.167.241.1 to 41.167.241.25441.167.241.255254
24341.167.242.0/2441.167.242.1 to 41.167.242.25441.167.242.255254
24441.167.243.0/2441.167.243.1 to 41.167.243.25441.167.243.255254
24541.167.244.0/2441.167.244.1 to 41.167.244.25441.167.244.255254
24641.167.245.0/2441.167.245.1 to 41.167.245.25441.167.245.255254
24741.167.246.0/2441.167.246.1 to 41.167.246.25441.167.246.255254
24841.167.247.0/2441.167.247.1 to 41.167.247.25441.167.247.255254
24941.167.248.0/2441.167.248.1 to 41.167.248.25441.167.248.255254
25041.167.249.0/2441.167.249.1 to 41.167.249.25441.167.249.255254
25141.167.250.0/2441.167.250.1 to 41.167.250.25441.167.250.255254
25241.167.251.0/2441.167.251.1 to 41.167.251.25441.167.251.255254
25341.167.252.0/2441.167.252.1 to 41.167.252.25441.167.252.255254
25441.167.253.0/2441.167.253.1 to 41.167.253.25441.167.253.255254
25541.167.254.0/2441.167.254.1 to 41.167.254.25441.167.254.255254
25641.167.255.0/2441.167.255.1 to 41.167.255.25441.167.255.255254

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.