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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.

Network41.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
41.0.0.0
Broadcast address
41.255.255.255
First usable
41.0.0.1
Last usable
41.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 29000000 · Integer 687865856 to 704643071
Reverse DNS zone
41.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101001..00000000.00000000.0000000041.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00101001..00000000.00000000.0000000041.0.0.0
Broadcast00101001..11111111.11111111.1111111141.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

41.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
141.0.0.0/1641.0.0.1 to 41.0.255.25441.0.255.25565,534
241.1.0.0/1641.1.0.1 to 41.1.255.25441.1.255.25565,534
341.2.0.0/1641.2.0.1 to 41.2.255.25441.2.255.25565,534
441.3.0.0/1641.3.0.1 to 41.3.255.25441.3.255.25565,534
541.4.0.0/1641.4.0.1 to 41.4.255.25441.4.255.25565,534
641.5.0.0/1641.5.0.1 to 41.5.255.25441.5.255.25565,534
741.6.0.0/1641.6.0.1 to 41.6.255.25441.6.255.25565,534
841.7.0.0/1641.7.0.1 to 41.7.255.25441.7.255.25565,534
941.8.0.0/1641.8.0.1 to 41.8.255.25441.8.255.25565,534
1041.9.0.0/1641.9.0.1 to 41.9.255.25441.9.255.25565,534
1141.10.0.0/1641.10.0.1 to 41.10.255.25441.10.255.25565,534
1241.11.0.0/1641.11.0.1 to 41.11.255.25441.11.255.25565,534
1341.12.0.0/1641.12.0.1 to 41.12.255.25441.12.255.25565,534
1441.13.0.0/1641.13.0.1 to 41.13.255.25441.13.255.25565,534
1541.14.0.0/1641.14.0.1 to 41.14.255.25441.14.255.25565,534
1641.15.0.0/1641.15.0.1 to 41.15.255.25441.15.255.25565,534
1741.16.0.0/1641.16.0.1 to 41.16.255.25441.16.255.25565,534
1841.17.0.0/1641.17.0.1 to 41.17.255.25441.17.255.25565,534
1941.18.0.0/1641.18.0.1 to 41.18.255.25441.18.255.25565,534
2041.19.0.0/1641.19.0.1 to 41.19.255.25441.19.255.25565,534
2141.20.0.0/1641.20.0.1 to 41.20.255.25441.20.255.25565,534
2241.21.0.0/1641.21.0.1 to 41.21.255.25441.21.255.25565,534
2341.22.0.0/1641.22.0.1 to 41.22.255.25441.22.255.25565,534
2441.23.0.0/1641.23.0.1 to 41.23.255.25441.23.255.25565,534
2541.24.0.0/1641.24.0.1 to 41.24.255.25441.24.255.25565,534
2641.25.0.0/1641.25.0.1 to 41.25.255.25441.25.255.25565,534
2741.26.0.0/1641.26.0.1 to 41.26.255.25441.26.255.25565,534
2841.27.0.0/1641.27.0.1 to 41.27.255.25441.27.255.25565,534
2941.28.0.0/1641.28.0.1 to 41.28.255.25441.28.255.25565,534
3041.29.0.0/1641.29.0.1 to 41.29.255.25441.29.255.25565,534
3141.30.0.0/1641.30.0.1 to 41.30.255.25441.30.255.25565,534
3241.31.0.0/1641.31.0.1 to 41.31.255.25441.31.255.25565,534
3341.32.0.0/1641.32.0.1 to 41.32.255.25441.32.255.25565,534
3441.33.0.0/1641.33.0.1 to 41.33.255.25441.33.255.25565,534
3541.34.0.0/1641.34.0.1 to 41.34.255.25441.34.255.25565,534
3641.35.0.0/1641.35.0.1 to 41.35.255.25441.35.255.25565,534
3741.36.0.0/1641.36.0.1 to 41.36.255.25441.36.255.25565,534
3841.37.0.0/1641.37.0.1 to 41.37.255.25441.37.255.25565,534
3941.38.0.0/1641.38.0.1 to 41.38.255.25441.38.255.25565,534
4041.39.0.0/1641.39.0.1 to 41.39.255.25441.39.255.25565,534
4141.40.0.0/1641.40.0.1 to 41.40.255.25441.40.255.25565,534
4241.41.0.0/1641.41.0.1 to 41.41.255.25441.41.255.25565,534
4341.42.0.0/1641.42.0.1 to 41.42.255.25441.42.255.25565,534
4441.43.0.0/1641.43.0.1 to 41.43.255.25441.43.255.25565,534
4541.44.0.0/1641.44.0.1 to 41.44.255.25441.44.255.25565,534
4641.45.0.0/1641.45.0.1 to 41.45.255.25441.45.255.25565,534
4741.46.0.0/1641.46.0.1 to 41.46.255.25441.46.255.25565,534
4841.47.0.0/1641.47.0.1 to 41.47.255.25441.47.255.25565,534
4941.48.0.0/1641.48.0.1 to 41.48.255.25441.48.255.25565,534
5041.49.0.0/1641.49.0.1 to 41.49.255.25441.49.255.25565,534
5141.50.0.0/1641.50.0.1 to 41.50.255.25441.50.255.25565,534
5241.51.0.0/1641.51.0.1 to 41.51.255.25441.51.255.25565,534
5341.52.0.0/1641.52.0.1 to 41.52.255.25441.52.255.25565,534
5441.53.0.0/1641.53.0.1 to 41.53.255.25441.53.255.25565,534
5541.54.0.0/1641.54.0.1 to 41.54.255.25441.54.255.25565,534
5641.55.0.0/1641.55.0.1 to 41.55.255.25441.55.255.25565,534
5741.56.0.0/1641.56.0.1 to 41.56.255.25441.56.255.25565,534
5841.57.0.0/1641.57.0.1 to 41.57.255.25441.57.255.25565,534
5941.58.0.0/1641.58.0.1 to 41.58.255.25441.58.255.25565,534
6041.59.0.0/1641.59.0.1 to 41.59.255.25441.59.255.25565,534
6141.60.0.0/1641.60.0.1 to 41.60.255.25441.60.255.25565,534
6241.61.0.0/1641.61.0.1 to 41.61.255.25441.61.255.25565,534
6341.62.0.0/1641.62.0.1 to 41.62.255.25441.62.255.25565,534
6441.63.0.0/1641.63.0.1 to 41.63.255.25441.63.255.25565,534
6541.64.0.0/1641.64.0.1 to 41.64.255.25441.64.255.25565,534
6641.65.0.0/1641.65.0.1 to 41.65.255.25441.65.255.25565,534
6741.66.0.0/1641.66.0.1 to 41.66.255.25441.66.255.25565,534
6841.67.0.0/1641.67.0.1 to 41.67.255.25441.67.255.25565,534
6941.68.0.0/1641.68.0.1 to 41.68.255.25441.68.255.25565,534
7041.69.0.0/1641.69.0.1 to 41.69.255.25441.69.255.25565,534
7141.70.0.0/1641.70.0.1 to 41.70.255.25441.70.255.25565,534
7241.71.0.0/1641.71.0.1 to 41.71.255.25441.71.255.25565,534
7341.72.0.0/1641.72.0.1 to 41.72.255.25441.72.255.25565,534
7441.73.0.0/1641.73.0.1 to 41.73.255.25441.73.255.25565,534
7541.74.0.0/1641.74.0.1 to 41.74.255.25441.74.255.25565,534
7641.75.0.0/1641.75.0.1 to 41.75.255.25441.75.255.25565,534
7741.76.0.0/1641.76.0.1 to 41.76.255.25441.76.255.25565,534
7841.77.0.0/1641.77.0.1 to 41.77.255.25441.77.255.25565,534
7941.78.0.0/1641.78.0.1 to 41.78.255.25441.78.255.25565,534
8041.79.0.0/1641.79.0.1 to 41.79.255.25441.79.255.25565,534
8141.80.0.0/1641.80.0.1 to 41.80.255.25441.80.255.25565,534
8241.81.0.0/1641.81.0.1 to 41.81.255.25441.81.255.25565,534
8341.82.0.0/1641.82.0.1 to 41.82.255.25441.82.255.25565,534
8441.83.0.0/1641.83.0.1 to 41.83.255.25441.83.255.25565,534
8541.84.0.0/1641.84.0.1 to 41.84.255.25441.84.255.25565,534
8641.85.0.0/1641.85.0.1 to 41.85.255.25441.85.255.25565,534
8741.86.0.0/1641.86.0.1 to 41.86.255.25441.86.255.25565,534
8841.87.0.0/1641.87.0.1 to 41.87.255.25441.87.255.25565,534
8941.88.0.0/1641.88.0.1 to 41.88.255.25441.88.255.25565,534
9041.89.0.0/1641.89.0.1 to 41.89.255.25441.89.255.25565,534
9141.90.0.0/1641.90.0.1 to 41.90.255.25441.90.255.25565,534
9241.91.0.0/1641.91.0.1 to 41.91.255.25441.91.255.25565,534
9341.92.0.0/1641.92.0.1 to 41.92.255.25441.92.255.25565,534
9441.93.0.0/1641.93.0.1 to 41.93.255.25441.93.255.25565,534
9541.94.0.0/1641.94.0.1 to 41.94.255.25441.94.255.25565,534
9641.95.0.0/1641.95.0.1 to 41.95.255.25441.95.255.25565,534
9741.96.0.0/1641.96.0.1 to 41.96.255.25441.96.255.25565,534
9841.97.0.0/1641.97.0.1 to 41.97.255.25441.97.255.25565,534
9941.98.0.0/1641.98.0.1 to 41.98.255.25441.98.255.25565,534
10041.99.0.0/1641.99.0.1 to 41.99.255.25441.99.255.25565,534
10141.100.0.0/1641.100.0.1 to 41.100.255.25441.100.255.25565,534
10241.101.0.0/1641.101.0.1 to 41.101.255.25441.101.255.25565,534
10341.102.0.0/1641.102.0.1 to 41.102.255.25441.102.255.25565,534
10441.103.0.0/1641.103.0.1 to 41.103.255.25441.103.255.25565,534
10541.104.0.0/1641.104.0.1 to 41.104.255.25441.104.255.25565,534
10641.105.0.0/1641.105.0.1 to 41.105.255.25441.105.255.25565,534
10741.106.0.0/1641.106.0.1 to 41.106.255.25441.106.255.25565,534
10841.107.0.0/1641.107.0.1 to 41.107.255.25441.107.255.25565,534
10941.108.0.0/1641.108.0.1 to 41.108.255.25441.108.255.25565,534
11041.109.0.0/1641.109.0.1 to 41.109.255.25441.109.255.25565,534
11141.110.0.0/1641.110.0.1 to 41.110.255.25441.110.255.25565,534
11241.111.0.0/1641.111.0.1 to 41.111.255.25441.111.255.25565,534
11341.112.0.0/1641.112.0.1 to 41.112.255.25441.112.255.25565,534
11441.113.0.0/1641.113.0.1 to 41.113.255.25441.113.255.25565,534
11541.114.0.0/1641.114.0.1 to 41.114.255.25441.114.255.25565,534
11641.115.0.0/1641.115.0.1 to 41.115.255.25441.115.255.25565,534
11741.116.0.0/1641.116.0.1 to 41.116.255.25441.116.255.25565,534
11841.117.0.0/1641.117.0.1 to 41.117.255.25441.117.255.25565,534
11941.118.0.0/1641.118.0.1 to 41.118.255.25441.118.255.25565,534
12041.119.0.0/1641.119.0.1 to 41.119.255.25441.119.255.25565,534
12141.120.0.0/1641.120.0.1 to 41.120.255.25441.120.255.25565,534
12241.121.0.0/1641.121.0.1 to 41.121.255.25441.121.255.25565,534
12341.122.0.0/1641.122.0.1 to 41.122.255.25441.122.255.25565,534
12441.123.0.0/1641.123.0.1 to 41.123.255.25441.123.255.25565,534
12541.124.0.0/1641.124.0.1 to 41.124.255.25441.124.255.25565,534
12641.125.0.0/1641.125.0.1 to 41.125.255.25441.125.255.25565,534
12741.126.0.0/1641.126.0.1 to 41.126.255.25441.126.255.25565,534
12841.127.0.0/1641.127.0.1 to 41.127.255.25441.127.255.25565,534
12941.128.0.0/1641.128.0.1 to 41.128.255.25441.128.255.25565,534
13041.129.0.0/1641.129.0.1 to 41.129.255.25441.129.255.25565,534
13141.130.0.0/1641.130.0.1 to 41.130.255.25441.130.255.25565,534
13241.131.0.0/1641.131.0.1 to 41.131.255.25441.131.255.25565,534
13341.132.0.0/1641.132.0.1 to 41.132.255.25441.132.255.25565,534
13441.133.0.0/1641.133.0.1 to 41.133.255.25441.133.255.25565,534
13541.134.0.0/1641.134.0.1 to 41.134.255.25441.134.255.25565,534
13641.135.0.0/1641.135.0.1 to 41.135.255.25441.135.255.25565,534
13741.136.0.0/1641.136.0.1 to 41.136.255.25441.136.255.25565,534
13841.137.0.0/1641.137.0.1 to 41.137.255.25441.137.255.25565,534
13941.138.0.0/1641.138.0.1 to 41.138.255.25441.138.255.25565,534
14041.139.0.0/1641.139.0.1 to 41.139.255.25441.139.255.25565,534
14141.140.0.0/1641.140.0.1 to 41.140.255.25441.140.255.25565,534
14241.141.0.0/1641.141.0.1 to 41.141.255.25441.141.255.25565,534
14341.142.0.0/1641.142.0.1 to 41.142.255.25441.142.255.25565,534
14441.143.0.0/1641.143.0.1 to 41.143.255.25441.143.255.25565,534
14541.144.0.0/1641.144.0.1 to 41.144.255.25441.144.255.25565,534
14641.145.0.0/1641.145.0.1 to 41.145.255.25441.145.255.25565,534
14741.146.0.0/1641.146.0.1 to 41.146.255.25441.146.255.25565,534
14841.147.0.0/1641.147.0.1 to 41.147.255.25441.147.255.25565,534
14941.148.0.0/1641.148.0.1 to 41.148.255.25441.148.255.25565,534
15041.149.0.0/1641.149.0.1 to 41.149.255.25441.149.255.25565,534
15141.150.0.0/1641.150.0.1 to 41.150.255.25441.150.255.25565,534
15241.151.0.0/1641.151.0.1 to 41.151.255.25441.151.255.25565,534
15341.152.0.0/1641.152.0.1 to 41.152.255.25441.152.255.25565,534
15441.153.0.0/1641.153.0.1 to 41.153.255.25441.153.255.25565,534
15541.154.0.0/1641.154.0.1 to 41.154.255.25441.154.255.25565,534
15641.155.0.0/1641.155.0.1 to 41.155.255.25441.155.255.25565,534
15741.156.0.0/1641.156.0.1 to 41.156.255.25441.156.255.25565,534
15841.157.0.0/1641.157.0.1 to 41.157.255.25441.157.255.25565,534
15941.158.0.0/1641.158.0.1 to 41.158.255.25441.158.255.25565,534
16041.159.0.0/1641.159.0.1 to 41.159.255.25441.159.255.25565,534
16141.160.0.0/1641.160.0.1 to 41.160.255.25441.160.255.25565,534
16241.161.0.0/1641.161.0.1 to 41.161.255.25441.161.255.25565,534
16341.162.0.0/1641.162.0.1 to 41.162.255.25441.162.255.25565,534
16441.163.0.0/1641.163.0.1 to 41.163.255.25441.163.255.25565,534
16541.164.0.0/1641.164.0.1 to 41.164.255.25441.164.255.25565,534
16641.165.0.0/1641.165.0.1 to 41.165.255.25441.165.255.25565,534
16741.166.0.0/1641.166.0.1 to 41.166.255.25441.166.255.25565,534
16841.167.0.0/1641.167.0.1 to 41.167.255.25441.167.255.25565,534
16941.168.0.0/1641.168.0.1 to 41.168.255.25441.168.255.25565,534
17041.169.0.0/1641.169.0.1 to 41.169.255.25441.169.255.25565,534
17141.170.0.0/1641.170.0.1 to 41.170.255.25441.170.255.25565,534
17241.171.0.0/1641.171.0.1 to 41.171.255.25441.171.255.25565,534
17341.172.0.0/1641.172.0.1 to 41.172.255.25441.172.255.25565,534
17441.173.0.0/1641.173.0.1 to 41.173.255.25441.173.255.25565,534
17541.174.0.0/1641.174.0.1 to 41.174.255.25441.174.255.25565,534
17641.175.0.0/1641.175.0.1 to 41.175.255.25441.175.255.25565,534
17741.176.0.0/1641.176.0.1 to 41.176.255.25441.176.255.25565,534
17841.177.0.0/1641.177.0.1 to 41.177.255.25441.177.255.25565,534
17941.178.0.0/1641.178.0.1 to 41.178.255.25441.178.255.25565,534
18041.179.0.0/1641.179.0.1 to 41.179.255.25441.179.255.25565,534
18141.180.0.0/1641.180.0.1 to 41.180.255.25441.180.255.25565,534
18241.181.0.0/1641.181.0.1 to 41.181.255.25441.181.255.25565,534
18341.182.0.0/1641.182.0.1 to 41.182.255.25441.182.255.25565,534
18441.183.0.0/1641.183.0.1 to 41.183.255.25441.183.255.25565,534
18541.184.0.0/1641.184.0.1 to 41.184.255.25441.184.255.25565,534
18641.185.0.0/1641.185.0.1 to 41.185.255.25441.185.255.25565,534
18741.186.0.0/1641.186.0.1 to 41.186.255.25441.186.255.25565,534
18841.187.0.0/1641.187.0.1 to 41.187.255.25441.187.255.25565,534
18941.188.0.0/1641.188.0.1 to 41.188.255.25441.188.255.25565,534
19041.189.0.0/1641.189.0.1 to 41.189.255.25441.189.255.25565,534
19141.190.0.0/1641.190.0.1 to 41.190.255.25441.190.255.25565,534
19241.191.0.0/1641.191.0.1 to 41.191.255.25441.191.255.25565,534
19341.192.0.0/1641.192.0.1 to 41.192.255.25441.192.255.25565,534
19441.193.0.0/1641.193.0.1 to 41.193.255.25441.193.255.25565,534
19541.194.0.0/1641.194.0.1 to 41.194.255.25441.194.255.25565,534
19641.195.0.0/1641.195.0.1 to 41.195.255.25441.195.255.25565,534
19741.196.0.0/1641.196.0.1 to 41.196.255.25441.196.255.25565,534
19841.197.0.0/1641.197.0.1 to 41.197.255.25441.197.255.25565,534
19941.198.0.0/1641.198.0.1 to 41.198.255.25441.198.255.25565,534
20041.199.0.0/1641.199.0.1 to 41.199.255.25441.199.255.25565,534
20141.200.0.0/1641.200.0.1 to 41.200.255.25441.200.255.25565,534
20241.201.0.0/1641.201.0.1 to 41.201.255.25441.201.255.25565,534
20341.202.0.0/1641.202.0.1 to 41.202.255.25441.202.255.25565,534
20441.203.0.0/1641.203.0.1 to 41.203.255.25441.203.255.25565,534
20541.204.0.0/1641.204.0.1 to 41.204.255.25441.204.255.25565,534
20641.205.0.0/1641.205.0.1 to 41.205.255.25441.205.255.25565,534
20741.206.0.0/1641.206.0.1 to 41.206.255.25441.206.255.25565,534
20841.207.0.0/1641.207.0.1 to 41.207.255.25441.207.255.25565,534
20941.208.0.0/1641.208.0.1 to 41.208.255.25441.208.255.25565,534
21041.209.0.0/1641.209.0.1 to 41.209.255.25441.209.255.25565,534
21141.210.0.0/1641.210.0.1 to 41.210.255.25441.210.255.25565,534
21241.211.0.0/1641.211.0.1 to 41.211.255.25441.211.255.25565,534
21341.212.0.0/1641.212.0.1 to 41.212.255.25441.212.255.25565,534
21441.213.0.0/1641.213.0.1 to 41.213.255.25441.213.255.25565,534
21541.214.0.0/1641.214.0.1 to 41.214.255.25441.214.255.25565,534
21641.215.0.0/1641.215.0.1 to 41.215.255.25441.215.255.25565,534
21741.216.0.0/1641.216.0.1 to 41.216.255.25441.216.255.25565,534
21841.217.0.0/1641.217.0.1 to 41.217.255.25441.217.255.25565,534
21941.218.0.0/1641.218.0.1 to 41.218.255.25441.218.255.25565,534
22041.219.0.0/1641.219.0.1 to 41.219.255.25441.219.255.25565,534
22141.220.0.0/1641.220.0.1 to 41.220.255.25441.220.255.25565,534
22241.221.0.0/1641.221.0.1 to 41.221.255.25441.221.255.25565,534
22341.222.0.0/1641.222.0.1 to 41.222.255.25441.222.255.25565,534
22441.223.0.0/1641.223.0.1 to 41.223.255.25441.223.255.25565,534
22541.224.0.0/1641.224.0.1 to 41.224.255.25441.224.255.25565,534
22641.225.0.0/1641.225.0.1 to 41.225.255.25441.225.255.25565,534
22741.226.0.0/1641.226.0.1 to 41.226.255.25441.226.255.25565,534
22841.227.0.0/1641.227.0.1 to 41.227.255.25441.227.255.25565,534
22941.228.0.0/1641.228.0.1 to 41.228.255.25441.228.255.25565,534
23041.229.0.0/1641.229.0.1 to 41.229.255.25441.229.255.25565,534
23141.230.0.0/1641.230.0.1 to 41.230.255.25441.230.255.25565,534
23241.231.0.0/1641.231.0.1 to 41.231.255.25441.231.255.25565,534
23341.232.0.0/1641.232.0.1 to 41.232.255.25441.232.255.25565,534
23441.233.0.0/1641.233.0.1 to 41.233.255.25441.233.255.25565,534
23541.234.0.0/1641.234.0.1 to 41.234.255.25441.234.255.25565,534
23641.235.0.0/1641.235.0.1 to 41.235.255.25441.235.255.25565,534
23741.236.0.0/1641.236.0.1 to 41.236.255.25441.236.255.25565,534
23841.237.0.0/1641.237.0.1 to 41.237.255.25441.237.255.25565,534
23941.238.0.0/1641.238.0.1 to 41.238.255.25441.238.255.25565,534
24041.239.0.0/1641.239.0.1 to 41.239.255.25441.239.255.25565,534
24141.240.0.0/1641.240.0.1 to 41.240.255.25441.240.255.25565,534
24241.241.0.0/1641.241.0.1 to 41.241.255.25441.241.255.25565,534
24341.242.0.0/1641.242.0.1 to 41.242.255.25441.242.255.25565,534
24441.243.0.0/1641.243.0.1 to 41.243.255.25441.243.255.25565,534
24541.244.0.0/1641.244.0.1 to 41.244.255.25441.244.255.25565,534
24641.245.0.0/1641.245.0.1 to 41.245.255.25441.245.255.25565,534
24741.246.0.0/1641.246.0.1 to 41.246.255.25441.246.255.25565,534
24841.247.0.0/1641.247.0.1 to 41.247.255.25441.247.255.25565,534
24941.248.0.0/1641.248.0.1 to 41.248.255.25441.248.255.25565,534
25041.249.0.0/1641.249.0.1 to 41.249.255.25441.249.255.25565,534
25141.250.0.0/1641.250.0.1 to 41.250.255.25441.250.255.25565,534
25241.251.0.0/1641.251.0.1 to 41.251.255.25441.251.255.25565,534
25341.252.0.0/1641.252.0.1 to 41.252.255.25441.252.255.25565,534
25441.253.0.0/1641.253.0.1 to 41.253.255.25441.253.255.25565,534
25541.254.0.0/1641.254.0.1 to 41.254.255.25441.254.255.25565,534
25641.255.0.0/1641.255.0.1 to 41.255.255.25441.255.255.25565,534

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.