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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.

Network76.0.0.0/6
Usable hosts67,108,862
Subnet mask252.0.0.0
Addresses67,108,864
Network address
76.0.0.0
Broadcast address
79.255.255.255
First usable
76.0.0.1
Last usable
79.255.255.254
Usable hosts
67,108,862 (67,108,864 less the network and broadcast addresses)
Subnet mask
252.0.0.0
Wildcard mask
3.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/6
Type
Public public
Old class
A (default /8)
As numbers
Hex 4C000000 · Integer 1275068416 to 1342177279
Reverse DNS zones
76.in-addr.arpa
77.in-addr.arpa
78.in-addr.arpa
79.in-addr.arpa
/6 is not on a 8-bit boundary, so it takes 4 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001100.00000000.00000000.0000000076.0.0.0
Subnet mask11111100.00000000.00000000.00000000252.0.0.0
Network01001100.00000000.00000000.0000000076.0.0.0
Broadcast01001111.11111111.11111111.1111111179.255.255.255
Split into smaller subnets/16
/7 (2)/8 (4)/9 (8)/10 (16)/11 (32)/12 (64)/13 (128)/14 (256)/15 (512)/16 (1,024)/17 (2,048)/18 (4,096)

76.0.0.0/6 makes 1,024 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
176.0.0.0/1676.0.0.1 to 76.0.255.25476.0.255.25565,534
276.1.0.0/1676.1.0.1 to 76.1.255.25476.1.255.25565,534
376.2.0.0/1676.2.0.1 to 76.2.255.25476.2.255.25565,534
476.3.0.0/1676.3.0.1 to 76.3.255.25476.3.255.25565,534
576.4.0.0/1676.4.0.1 to 76.4.255.25476.4.255.25565,534
676.5.0.0/1676.5.0.1 to 76.5.255.25476.5.255.25565,534
776.6.0.0/1676.6.0.1 to 76.6.255.25476.6.255.25565,534
876.7.0.0/1676.7.0.1 to 76.7.255.25476.7.255.25565,534
976.8.0.0/1676.8.0.1 to 76.8.255.25476.8.255.25565,534
1076.9.0.0/1676.9.0.1 to 76.9.255.25476.9.255.25565,534
1176.10.0.0/1676.10.0.1 to 76.10.255.25476.10.255.25565,534
1276.11.0.0/1676.11.0.1 to 76.11.255.25476.11.255.25565,534
1376.12.0.0/1676.12.0.1 to 76.12.255.25476.12.255.25565,534
1476.13.0.0/1676.13.0.1 to 76.13.255.25476.13.255.25565,534
1576.14.0.0/1676.14.0.1 to 76.14.255.25476.14.255.25565,534
1676.15.0.0/1676.15.0.1 to 76.15.255.25476.15.255.25565,534
1776.16.0.0/1676.16.0.1 to 76.16.255.25476.16.255.25565,534
1876.17.0.0/1676.17.0.1 to 76.17.255.25476.17.255.25565,534
1976.18.0.0/1676.18.0.1 to 76.18.255.25476.18.255.25565,534
2076.19.0.0/1676.19.0.1 to 76.19.255.25476.19.255.25565,534
2176.20.0.0/1676.20.0.1 to 76.20.255.25476.20.255.25565,534
2276.21.0.0/1676.21.0.1 to 76.21.255.25476.21.255.25565,534
2376.22.0.0/1676.22.0.1 to 76.22.255.25476.22.255.25565,534
2476.23.0.0/1676.23.0.1 to 76.23.255.25476.23.255.25565,534
2576.24.0.0/1676.24.0.1 to 76.24.255.25476.24.255.25565,534
2676.25.0.0/1676.25.0.1 to 76.25.255.25476.25.255.25565,534
2776.26.0.0/1676.26.0.1 to 76.26.255.25476.26.255.25565,534
2876.27.0.0/1676.27.0.1 to 76.27.255.25476.27.255.25565,534
2976.28.0.0/1676.28.0.1 to 76.28.255.25476.28.255.25565,534
3076.29.0.0/1676.29.0.1 to 76.29.255.25476.29.255.25565,534
3176.30.0.0/1676.30.0.1 to 76.30.255.25476.30.255.25565,534
3276.31.0.0/1676.31.0.1 to 76.31.255.25476.31.255.25565,534
3376.32.0.0/1676.32.0.1 to 76.32.255.25476.32.255.25565,534
3476.33.0.0/1676.33.0.1 to 76.33.255.25476.33.255.25565,534
3576.34.0.0/1676.34.0.1 to 76.34.255.25476.34.255.25565,534
3676.35.0.0/1676.35.0.1 to 76.35.255.25476.35.255.25565,534
3776.36.0.0/1676.36.0.1 to 76.36.255.25476.36.255.25565,534
3876.37.0.0/1676.37.0.1 to 76.37.255.25476.37.255.25565,534
3976.38.0.0/1676.38.0.1 to 76.38.255.25476.38.255.25565,534
4076.39.0.0/1676.39.0.1 to 76.39.255.25476.39.255.25565,534
4176.40.0.0/1676.40.0.1 to 76.40.255.25476.40.255.25565,534
4276.41.0.0/1676.41.0.1 to 76.41.255.25476.41.255.25565,534
4376.42.0.0/1676.42.0.1 to 76.42.255.25476.42.255.25565,534
4476.43.0.0/1676.43.0.1 to 76.43.255.25476.43.255.25565,534
4576.44.0.0/1676.44.0.1 to 76.44.255.25476.44.255.25565,534
4676.45.0.0/1676.45.0.1 to 76.45.255.25476.45.255.25565,534
4776.46.0.0/1676.46.0.1 to 76.46.255.25476.46.255.25565,534
4876.47.0.0/1676.47.0.1 to 76.47.255.25476.47.255.25565,534
4976.48.0.0/1676.48.0.1 to 76.48.255.25476.48.255.25565,534
5076.49.0.0/1676.49.0.1 to 76.49.255.25476.49.255.25565,534
5176.50.0.0/1676.50.0.1 to 76.50.255.25476.50.255.25565,534
5276.51.0.0/1676.51.0.1 to 76.51.255.25476.51.255.25565,534
5376.52.0.0/1676.52.0.1 to 76.52.255.25476.52.255.25565,534
5476.53.0.0/1676.53.0.1 to 76.53.255.25476.53.255.25565,534
5576.54.0.0/1676.54.0.1 to 76.54.255.25476.54.255.25565,534
5676.55.0.0/1676.55.0.1 to 76.55.255.25476.55.255.25565,534
5776.56.0.0/1676.56.0.1 to 76.56.255.25476.56.255.25565,534
5876.57.0.0/1676.57.0.1 to 76.57.255.25476.57.255.25565,534
5976.58.0.0/1676.58.0.1 to 76.58.255.25476.58.255.25565,534
6076.59.0.0/1676.59.0.1 to 76.59.255.25476.59.255.25565,534
6176.60.0.0/1676.60.0.1 to 76.60.255.25476.60.255.25565,534
6276.61.0.0/1676.61.0.1 to 76.61.255.25476.61.255.25565,534
6376.62.0.0/1676.62.0.1 to 76.62.255.25476.62.255.25565,534
6476.63.0.0/1676.63.0.1 to 76.63.255.25476.63.255.25565,534
6576.64.0.0/1676.64.0.1 to 76.64.255.25476.64.255.25565,534
6676.65.0.0/1676.65.0.1 to 76.65.255.25476.65.255.25565,534
6776.66.0.0/1676.66.0.1 to 76.66.255.25476.66.255.25565,534
6876.67.0.0/1676.67.0.1 to 76.67.255.25476.67.255.25565,534
6976.68.0.0/1676.68.0.1 to 76.68.255.25476.68.255.25565,534
7076.69.0.0/1676.69.0.1 to 76.69.255.25476.69.255.25565,534
7176.70.0.0/1676.70.0.1 to 76.70.255.25476.70.255.25565,534
7276.71.0.0/1676.71.0.1 to 76.71.255.25476.71.255.25565,534
7376.72.0.0/1676.72.0.1 to 76.72.255.25476.72.255.25565,534
7476.73.0.0/1676.73.0.1 to 76.73.255.25476.73.255.25565,534
7576.74.0.0/1676.74.0.1 to 76.74.255.25476.74.255.25565,534
7676.75.0.0/1676.75.0.1 to 76.75.255.25476.75.255.25565,534
7776.76.0.0/1676.76.0.1 to 76.76.255.25476.76.255.25565,534
7876.77.0.0/1676.77.0.1 to 76.77.255.25476.77.255.25565,534
7976.78.0.0/1676.78.0.1 to 76.78.255.25476.78.255.25565,534
8076.79.0.0/1676.79.0.1 to 76.79.255.25476.79.255.25565,534
8176.80.0.0/1676.80.0.1 to 76.80.255.25476.80.255.25565,534
8276.81.0.0/1676.81.0.1 to 76.81.255.25476.81.255.25565,534
8376.82.0.0/1676.82.0.1 to 76.82.255.25476.82.255.25565,534
8476.83.0.0/1676.83.0.1 to 76.83.255.25476.83.255.25565,534
8576.84.0.0/1676.84.0.1 to 76.84.255.25476.84.255.25565,534
8676.85.0.0/1676.85.0.1 to 76.85.255.25476.85.255.25565,534
8776.86.0.0/1676.86.0.1 to 76.86.255.25476.86.255.25565,534
8876.87.0.0/1676.87.0.1 to 76.87.255.25476.87.255.25565,534
8976.88.0.0/1676.88.0.1 to 76.88.255.25476.88.255.25565,534
9076.89.0.0/1676.89.0.1 to 76.89.255.25476.89.255.25565,534
9176.90.0.0/1676.90.0.1 to 76.90.255.25476.90.255.25565,534
9276.91.0.0/1676.91.0.1 to 76.91.255.25476.91.255.25565,534
9376.92.0.0/1676.92.0.1 to 76.92.255.25476.92.255.25565,534
9476.93.0.0/1676.93.0.1 to 76.93.255.25476.93.255.25565,534
9576.94.0.0/1676.94.0.1 to 76.94.255.25476.94.255.25565,534
9676.95.0.0/1676.95.0.1 to 76.95.255.25476.95.255.25565,534
9776.96.0.0/1676.96.0.1 to 76.96.255.25476.96.255.25565,534
9876.97.0.0/1676.97.0.1 to 76.97.255.25476.97.255.25565,534
9976.98.0.0/1676.98.0.1 to 76.98.255.25476.98.255.25565,534
10076.99.0.0/1676.99.0.1 to 76.99.255.25476.99.255.25565,534
10176.100.0.0/1676.100.0.1 to 76.100.255.25476.100.255.25565,534
10276.101.0.0/1676.101.0.1 to 76.101.255.25476.101.255.25565,534
10376.102.0.0/1676.102.0.1 to 76.102.255.25476.102.255.25565,534
10476.103.0.0/1676.103.0.1 to 76.103.255.25476.103.255.25565,534
10576.104.0.0/1676.104.0.1 to 76.104.255.25476.104.255.25565,534
10676.105.0.0/1676.105.0.1 to 76.105.255.25476.105.255.25565,534
10776.106.0.0/1676.106.0.1 to 76.106.255.25476.106.255.25565,534
10876.107.0.0/1676.107.0.1 to 76.107.255.25476.107.255.25565,534
10976.108.0.0/1676.108.0.1 to 76.108.255.25476.108.255.25565,534
11076.109.0.0/1676.109.0.1 to 76.109.255.25476.109.255.25565,534
11176.110.0.0/1676.110.0.1 to 76.110.255.25476.110.255.25565,534
11276.111.0.0/1676.111.0.1 to 76.111.255.25476.111.255.25565,534
11376.112.0.0/1676.112.0.1 to 76.112.255.25476.112.255.25565,534
11476.113.0.0/1676.113.0.1 to 76.113.255.25476.113.255.25565,534
11576.114.0.0/1676.114.0.1 to 76.114.255.25476.114.255.25565,534
11676.115.0.0/1676.115.0.1 to 76.115.255.25476.115.255.25565,534
11776.116.0.0/1676.116.0.1 to 76.116.255.25476.116.255.25565,534
11876.117.0.0/1676.117.0.1 to 76.117.255.25476.117.255.25565,534
11976.118.0.0/1676.118.0.1 to 76.118.255.25476.118.255.25565,534
12076.119.0.0/1676.119.0.1 to 76.119.255.25476.119.255.25565,534
12176.120.0.0/1676.120.0.1 to 76.120.255.25476.120.255.25565,534
12276.121.0.0/1676.121.0.1 to 76.121.255.25476.121.255.25565,534
12376.122.0.0/1676.122.0.1 to 76.122.255.25476.122.255.25565,534
12476.123.0.0/1676.123.0.1 to 76.123.255.25476.123.255.25565,534
12576.124.0.0/1676.124.0.1 to 76.124.255.25476.124.255.25565,534
12676.125.0.0/1676.125.0.1 to 76.125.255.25476.125.255.25565,534
12776.126.0.0/1676.126.0.1 to 76.126.255.25476.126.255.25565,534
12876.127.0.0/1676.127.0.1 to 76.127.255.25476.127.255.25565,534
12976.128.0.0/1676.128.0.1 to 76.128.255.25476.128.255.25565,534
13076.129.0.0/1676.129.0.1 to 76.129.255.25476.129.255.25565,534
13176.130.0.0/1676.130.0.1 to 76.130.255.25476.130.255.25565,534
13276.131.0.0/1676.131.0.1 to 76.131.255.25476.131.255.25565,534
13376.132.0.0/1676.132.0.1 to 76.132.255.25476.132.255.25565,534
13476.133.0.0/1676.133.0.1 to 76.133.255.25476.133.255.25565,534
13576.134.0.0/1676.134.0.1 to 76.134.255.25476.134.255.25565,534
13676.135.0.0/1676.135.0.1 to 76.135.255.25476.135.255.25565,534
13776.136.0.0/1676.136.0.1 to 76.136.255.25476.136.255.25565,534
13876.137.0.0/1676.137.0.1 to 76.137.255.25476.137.255.25565,534
13976.138.0.0/1676.138.0.1 to 76.138.255.25476.138.255.25565,534
14076.139.0.0/1676.139.0.1 to 76.139.255.25476.139.255.25565,534
14176.140.0.0/1676.140.0.1 to 76.140.255.25476.140.255.25565,534
14276.141.0.0/1676.141.0.1 to 76.141.255.25476.141.255.25565,534
14376.142.0.0/1676.142.0.1 to 76.142.255.25476.142.255.25565,534
14476.143.0.0/1676.143.0.1 to 76.143.255.25476.143.255.25565,534
14576.144.0.0/1676.144.0.1 to 76.144.255.25476.144.255.25565,534
14676.145.0.0/1676.145.0.1 to 76.145.255.25476.145.255.25565,534
14776.146.0.0/1676.146.0.1 to 76.146.255.25476.146.255.25565,534
14876.147.0.0/1676.147.0.1 to 76.147.255.25476.147.255.25565,534
14976.148.0.0/1676.148.0.1 to 76.148.255.25476.148.255.25565,534
15076.149.0.0/1676.149.0.1 to 76.149.255.25476.149.255.25565,534
15176.150.0.0/1676.150.0.1 to 76.150.255.25476.150.255.25565,534
15276.151.0.0/1676.151.0.1 to 76.151.255.25476.151.255.25565,534
15376.152.0.0/1676.152.0.1 to 76.152.255.25476.152.255.25565,534
15476.153.0.0/1676.153.0.1 to 76.153.255.25476.153.255.25565,534
15576.154.0.0/1676.154.0.1 to 76.154.255.25476.154.255.25565,534
15676.155.0.0/1676.155.0.1 to 76.155.255.25476.155.255.25565,534
15776.156.0.0/1676.156.0.1 to 76.156.255.25476.156.255.25565,534
15876.157.0.0/1676.157.0.1 to 76.157.255.25476.157.255.25565,534
15976.158.0.0/1676.158.0.1 to 76.158.255.25476.158.255.25565,534
16076.159.0.0/1676.159.0.1 to 76.159.255.25476.159.255.25565,534
16176.160.0.0/1676.160.0.1 to 76.160.255.25476.160.255.25565,534
16276.161.0.0/1676.161.0.1 to 76.161.255.25476.161.255.25565,534
16376.162.0.0/1676.162.0.1 to 76.162.255.25476.162.255.25565,534
16476.163.0.0/1676.163.0.1 to 76.163.255.25476.163.255.25565,534
16576.164.0.0/1676.164.0.1 to 76.164.255.25476.164.255.25565,534
16676.165.0.0/1676.165.0.1 to 76.165.255.25476.165.255.25565,534
16776.166.0.0/1676.166.0.1 to 76.166.255.25476.166.255.25565,534
16876.167.0.0/1676.167.0.1 to 76.167.255.25476.167.255.25565,534
16976.168.0.0/1676.168.0.1 to 76.168.255.25476.168.255.25565,534
17076.169.0.0/1676.169.0.1 to 76.169.255.25476.169.255.25565,534
17176.170.0.0/1676.170.0.1 to 76.170.255.25476.170.255.25565,534
17276.171.0.0/1676.171.0.1 to 76.171.255.25476.171.255.25565,534
17376.172.0.0/1676.172.0.1 to 76.172.255.25476.172.255.25565,534
17476.173.0.0/1676.173.0.1 to 76.173.255.25476.173.255.25565,534
17576.174.0.0/1676.174.0.1 to 76.174.255.25476.174.255.25565,534
17676.175.0.0/1676.175.0.1 to 76.175.255.25476.175.255.25565,534
17776.176.0.0/1676.176.0.1 to 76.176.255.25476.176.255.25565,534
17876.177.0.0/1676.177.0.1 to 76.177.255.25476.177.255.25565,534
17976.178.0.0/1676.178.0.1 to 76.178.255.25476.178.255.25565,534
18076.179.0.0/1676.179.0.1 to 76.179.255.25476.179.255.25565,534
18176.180.0.0/1676.180.0.1 to 76.180.255.25476.180.255.25565,534
18276.181.0.0/1676.181.0.1 to 76.181.255.25476.181.255.25565,534
18376.182.0.0/1676.182.0.1 to 76.182.255.25476.182.255.25565,534
18476.183.0.0/1676.183.0.1 to 76.183.255.25476.183.255.25565,534
18576.184.0.0/1676.184.0.1 to 76.184.255.25476.184.255.25565,534
18676.185.0.0/1676.185.0.1 to 76.185.255.25476.185.255.25565,534
18776.186.0.0/1676.186.0.1 to 76.186.255.25476.186.255.25565,534
18876.187.0.0/1676.187.0.1 to 76.187.255.25476.187.255.25565,534
18976.188.0.0/1676.188.0.1 to 76.188.255.25476.188.255.25565,534
19076.189.0.0/1676.189.0.1 to 76.189.255.25476.189.255.25565,534
19176.190.0.0/1676.190.0.1 to 76.190.255.25476.190.255.25565,534
19276.191.0.0/1676.191.0.1 to 76.191.255.25476.191.255.25565,534
19376.192.0.0/1676.192.0.1 to 76.192.255.25476.192.255.25565,534
19476.193.0.0/1676.193.0.1 to 76.193.255.25476.193.255.25565,534
19576.194.0.0/1676.194.0.1 to 76.194.255.25476.194.255.25565,534
19676.195.0.0/1676.195.0.1 to 76.195.255.25476.195.255.25565,534
19776.196.0.0/1676.196.0.1 to 76.196.255.25476.196.255.25565,534
19876.197.0.0/1676.197.0.1 to 76.197.255.25476.197.255.25565,534
19976.198.0.0/1676.198.0.1 to 76.198.255.25476.198.255.25565,534
20076.199.0.0/1676.199.0.1 to 76.199.255.25476.199.255.25565,534
20176.200.0.0/1676.200.0.1 to 76.200.255.25476.200.255.25565,534
20276.201.0.0/1676.201.0.1 to 76.201.255.25476.201.255.25565,534
20376.202.0.0/1676.202.0.1 to 76.202.255.25476.202.255.25565,534
20476.203.0.0/1676.203.0.1 to 76.203.255.25476.203.255.25565,534
20576.204.0.0/1676.204.0.1 to 76.204.255.25476.204.255.25565,534
20676.205.0.0/1676.205.0.1 to 76.205.255.25476.205.255.25565,534
20776.206.0.0/1676.206.0.1 to 76.206.255.25476.206.255.25565,534
20876.207.0.0/1676.207.0.1 to 76.207.255.25476.207.255.25565,534
20976.208.0.0/1676.208.0.1 to 76.208.255.25476.208.255.25565,534
21076.209.0.0/1676.209.0.1 to 76.209.255.25476.209.255.25565,534
21176.210.0.0/1676.210.0.1 to 76.210.255.25476.210.255.25565,534
21276.211.0.0/1676.211.0.1 to 76.211.255.25476.211.255.25565,534
21376.212.0.0/1676.212.0.1 to 76.212.255.25476.212.255.25565,534
21476.213.0.0/1676.213.0.1 to 76.213.255.25476.213.255.25565,534
21576.214.0.0/1676.214.0.1 to 76.214.255.25476.214.255.25565,534
21676.215.0.0/1676.215.0.1 to 76.215.255.25476.215.255.25565,534
21776.216.0.0/1676.216.0.1 to 76.216.255.25476.216.255.25565,534
21876.217.0.0/1676.217.0.1 to 76.217.255.25476.217.255.25565,534
21976.218.0.0/1676.218.0.1 to 76.218.255.25476.218.255.25565,534
22076.219.0.0/1676.219.0.1 to 76.219.255.25476.219.255.25565,534
22176.220.0.0/1676.220.0.1 to 76.220.255.25476.220.255.25565,534
22276.221.0.0/1676.221.0.1 to 76.221.255.25476.221.255.25565,534
22376.222.0.0/1676.222.0.1 to 76.222.255.25476.222.255.25565,534
22476.223.0.0/1676.223.0.1 to 76.223.255.25476.223.255.25565,534
22576.224.0.0/1676.224.0.1 to 76.224.255.25476.224.255.25565,534
22676.225.0.0/1676.225.0.1 to 76.225.255.25476.225.255.25565,534
22776.226.0.0/1676.226.0.1 to 76.226.255.25476.226.255.25565,534
22876.227.0.0/1676.227.0.1 to 76.227.255.25476.227.255.25565,534
22976.228.0.0/1676.228.0.1 to 76.228.255.25476.228.255.25565,534
23076.229.0.0/1676.229.0.1 to 76.229.255.25476.229.255.25565,534
23176.230.0.0/1676.230.0.1 to 76.230.255.25476.230.255.25565,534
23276.231.0.0/1676.231.0.1 to 76.231.255.25476.231.255.25565,534
23376.232.0.0/1676.232.0.1 to 76.232.255.25476.232.255.25565,534
23476.233.0.0/1676.233.0.1 to 76.233.255.25476.233.255.25565,534
23576.234.0.0/1676.234.0.1 to 76.234.255.25476.234.255.25565,534
23676.235.0.0/1676.235.0.1 to 76.235.255.25476.235.255.25565,534
23776.236.0.0/1676.236.0.1 to 76.236.255.25476.236.255.25565,534
23876.237.0.0/1676.237.0.1 to 76.237.255.25476.237.255.25565,534
23976.238.0.0/1676.238.0.1 to 76.238.255.25476.238.255.25565,534
24076.239.0.0/1676.239.0.1 to 76.239.255.25476.239.255.25565,534
24176.240.0.0/1676.240.0.1 to 76.240.255.25476.240.255.25565,534
24276.241.0.0/1676.241.0.1 to 76.241.255.25476.241.255.25565,534
24376.242.0.0/1676.242.0.1 to 76.242.255.25476.242.255.25565,534
24476.243.0.0/1676.243.0.1 to 76.243.255.25476.243.255.25565,534
24576.244.0.0/1676.244.0.1 to 76.244.255.25476.244.255.25565,534
24676.245.0.0/1676.245.0.1 to 76.245.255.25476.245.255.25565,534
24776.246.0.0/1676.246.0.1 to 76.246.255.25476.246.255.25565,534
24876.247.0.0/1676.247.0.1 to 76.247.255.25476.247.255.25565,534
24976.248.0.0/1676.248.0.1 to 76.248.255.25476.248.255.25565,534
25076.249.0.0/1676.249.0.1 to 76.249.255.25476.249.255.25565,534
25176.250.0.0/1676.250.0.1 to 76.250.255.25476.250.255.25565,534
25276.251.0.0/1676.251.0.1 to 76.251.255.25476.251.255.25565,534
25376.252.0.0/1676.252.0.1 to 76.252.255.25476.252.255.25565,534
25476.253.0.0/1676.253.0.1 to 76.253.255.25476.253.255.25565,534
25576.254.0.0/1676.254.0.1 to 76.254.255.25476.254.255.25565,534
25676.255.0.0/1676.255.0.1 to 76.255.255.25476.255.255.25565,534

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.