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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.

Network57.192.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
57.192.0.0
Broadcast address
57.255.255.255
First usable
57.192.0.1
Last usable
57.255.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 39C00000 · Integer 968884224 to 973078527
Reverse DNS zones
192.57.in-addr.arpa
193.57.in-addr.arpa
194.57.in-addr.arpa
195.57.in-addr.arpa
196.57.in-addr.arpa
197.57.in-addr.arpa
198.57.in-addr.arpa
199.57.in-addr.arpa
200.57.in-addr.arpa
201.57.in-addr.arpa
202.57.in-addr.arpa
203.57.in-addr.arpa
204.57.in-addr.arpa
205.57.in-addr.arpa
206.57.in-addr.arpa
207.57.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111001.11000000.00000000.0000000057.192.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00111001.11000000.00000000.0000000057.192.0.0
Broadcast00111001.11111111.11111111.1111111157.255.255.255
Split into smaller subnets/22
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

57.192.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
157.192.0.0/2257.192.0.1 to 57.192.3.25457.192.3.2551,022
257.192.4.0/2257.192.4.1 to 57.192.7.25457.192.7.2551,022
357.192.8.0/2257.192.8.1 to 57.192.11.25457.192.11.2551,022
457.192.12.0/2257.192.12.1 to 57.192.15.25457.192.15.2551,022
557.192.16.0/2257.192.16.1 to 57.192.19.25457.192.19.2551,022
657.192.20.0/2257.192.20.1 to 57.192.23.25457.192.23.2551,022
757.192.24.0/2257.192.24.1 to 57.192.27.25457.192.27.2551,022
857.192.28.0/2257.192.28.1 to 57.192.31.25457.192.31.2551,022
957.192.32.0/2257.192.32.1 to 57.192.35.25457.192.35.2551,022
1057.192.36.0/2257.192.36.1 to 57.192.39.25457.192.39.2551,022
1157.192.40.0/2257.192.40.1 to 57.192.43.25457.192.43.2551,022
1257.192.44.0/2257.192.44.1 to 57.192.47.25457.192.47.2551,022
1357.192.48.0/2257.192.48.1 to 57.192.51.25457.192.51.2551,022
1457.192.52.0/2257.192.52.1 to 57.192.55.25457.192.55.2551,022
1557.192.56.0/2257.192.56.1 to 57.192.59.25457.192.59.2551,022
1657.192.60.0/2257.192.60.1 to 57.192.63.25457.192.63.2551,022
1757.192.64.0/2257.192.64.1 to 57.192.67.25457.192.67.2551,022
1857.192.68.0/2257.192.68.1 to 57.192.71.25457.192.71.2551,022
1957.192.72.0/2257.192.72.1 to 57.192.75.25457.192.75.2551,022
2057.192.76.0/2257.192.76.1 to 57.192.79.25457.192.79.2551,022
2157.192.80.0/2257.192.80.1 to 57.192.83.25457.192.83.2551,022
2257.192.84.0/2257.192.84.1 to 57.192.87.25457.192.87.2551,022
2357.192.88.0/2257.192.88.1 to 57.192.91.25457.192.91.2551,022
2457.192.92.0/2257.192.92.1 to 57.192.95.25457.192.95.2551,022
2557.192.96.0/2257.192.96.1 to 57.192.99.25457.192.99.2551,022
2657.192.100.0/2257.192.100.1 to 57.192.103.25457.192.103.2551,022
2757.192.104.0/2257.192.104.1 to 57.192.107.25457.192.107.2551,022
2857.192.108.0/2257.192.108.1 to 57.192.111.25457.192.111.2551,022
2957.192.112.0/2257.192.112.1 to 57.192.115.25457.192.115.2551,022
3057.192.116.0/2257.192.116.1 to 57.192.119.25457.192.119.2551,022
3157.192.120.0/2257.192.120.1 to 57.192.123.25457.192.123.2551,022
3257.192.124.0/2257.192.124.1 to 57.192.127.25457.192.127.2551,022
3357.192.128.0/2257.192.128.1 to 57.192.131.25457.192.131.2551,022
3457.192.132.0/2257.192.132.1 to 57.192.135.25457.192.135.2551,022
3557.192.136.0/2257.192.136.1 to 57.192.139.25457.192.139.2551,022
3657.192.140.0/2257.192.140.1 to 57.192.143.25457.192.143.2551,022
3757.192.144.0/2257.192.144.1 to 57.192.147.25457.192.147.2551,022
3857.192.148.0/2257.192.148.1 to 57.192.151.25457.192.151.2551,022
3957.192.152.0/2257.192.152.1 to 57.192.155.25457.192.155.2551,022
4057.192.156.0/2257.192.156.1 to 57.192.159.25457.192.159.2551,022
4157.192.160.0/2257.192.160.1 to 57.192.163.25457.192.163.2551,022
4257.192.164.0/2257.192.164.1 to 57.192.167.25457.192.167.2551,022
4357.192.168.0/2257.192.168.1 to 57.192.171.25457.192.171.2551,022
4457.192.172.0/2257.192.172.1 to 57.192.175.25457.192.175.2551,022
4557.192.176.0/2257.192.176.1 to 57.192.179.25457.192.179.2551,022
4657.192.180.0/2257.192.180.1 to 57.192.183.25457.192.183.2551,022
4757.192.184.0/2257.192.184.1 to 57.192.187.25457.192.187.2551,022
4857.192.188.0/2257.192.188.1 to 57.192.191.25457.192.191.2551,022
4957.192.192.0/2257.192.192.1 to 57.192.195.25457.192.195.2551,022
5057.192.196.0/2257.192.196.1 to 57.192.199.25457.192.199.2551,022
5157.192.200.0/2257.192.200.1 to 57.192.203.25457.192.203.2551,022
5257.192.204.0/2257.192.204.1 to 57.192.207.25457.192.207.2551,022
5357.192.208.0/2257.192.208.1 to 57.192.211.25457.192.211.2551,022
5457.192.212.0/2257.192.212.1 to 57.192.215.25457.192.215.2551,022
5557.192.216.0/2257.192.216.1 to 57.192.219.25457.192.219.2551,022
5657.192.220.0/2257.192.220.1 to 57.192.223.25457.192.223.2551,022
5757.192.224.0/2257.192.224.1 to 57.192.227.25457.192.227.2551,022
5857.192.228.0/2257.192.228.1 to 57.192.231.25457.192.231.2551,022
5957.192.232.0/2257.192.232.1 to 57.192.235.25457.192.235.2551,022
6057.192.236.0/2257.192.236.1 to 57.192.239.25457.192.239.2551,022
6157.192.240.0/2257.192.240.1 to 57.192.243.25457.192.243.2551,022
6257.192.244.0/2257.192.244.1 to 57.192.247.25457.192.247.2551,022
6357.192.248.0/2257.192.248.1 to 57.192.251.25457.192.251.2551,022
6457.192.252.0/2257.192.252.1 to 57.192.255.25457.192.255.2551,022
6557.193.0.0/2257.193.0.1 to 57.193.3.25457.193.3.2551,022
6657.193.4.0/2257.193.4.1 to 57.193.7.25457.193.7.2551,022
6757.193.8.0/2257.193.8.1 to 57.193.11.25457.193.11.2551,022
6857.193.12.0/2257.193.12.1 to 57.193.15.25457.193.15.2551,022
6957.193.16.0/2257.193.16.1 to 57.193.19.25457.193.19.2551,022
7057.193.20.0/2257.193.20.1 to 57.193.23.25457.193.23.2551,022
7157.193.24.0/2257.193.24.1 to 57.193.27.25457.193.27.2551,022
7257.193.28.0/2257.193.28.1 to 57.193.31.25457.193.31.2551,022
7357.193.32.0/2257.193.32.1 to 57.193.35.25457.193.35.2551,022
7457.193.36.0/2257.193.36.1 to 57.193.39.25457.193.39.2551,022
7557.193.40.0/2257.193.40.1 to 57.193.43.25457.193.43.2551,022
7657.193.44.0/2257.193.44.1 to 57.193.47.25457.193.47.2551,022
7757.193.48.0/2257.193.48.1 to 57.193.51.25457.193.51.2551,022
7857.193.52.0/2257.193.52.1 to 57.193.55.25457.193.55.2551,022
7957.193.56.0/2257.193.56.1 to 57.193.59.25457.193.59.2551,022
8057.193.60.0/2257.193.60.1 to 57.193.63.25457.193.63.2551,022
8157.193.64.0/2257.193.64.1 to 57.193.67.25457.193.67.2551,022
8257.193.68.0/2257.193.68.1 to 57.193.71.25457.193.71.2551,022
8357.193.72.0/2257.193.72.1 to 57.193.75.25457.193.75.2551,022
8457.193.76.0/2257.193.76.1 to 57.193.79.25457.193.79.2551,022
8557.193.80.0/2257.193.80.1 to 57.193.83.25457.193.83.2551,022
8657.193.84.0/2257.193.84.1 to 57.193.87.25457.193.87.2551,022
8757.193.88.0/2257.193.88.1 to 57.193.91.25457.193.91.2551,022
8857.193.92.0/2257.193.92.1 to 57.193.95.25457.193.95.2551,022
8957.193.96.0/2257.193.96.1 to 57.193.99.25457.193.99.2551,022
9057.193.100.0/2257.193.100.1 to 57.193.103.25457.193.103.2551,022
9157.193.104.0/2257.193.104.1 to 57.193.107.25457.193.107.2551,022
9257.193.108.0/2257.193.108.1 to 57.193.111.25457.193.111.2551,022
9357.193.112.0/2257.193.112.1 to 57.193.115.25457.193.115.2551,022
9457.193.116.0/2257.193.116.1 to 57.193.119.25457.193.119.2551,022
9557.193.120.0/2257.193.120.1 to 57.193.123.25457.193.123.2551,022
9657.193.124.0/2257.193.124.1 to 57.193.127.25457.193.127.2551,022
9757.193.128.0/2257.193.128.1 to 57.193.131.25457.193.131.2551,022
9857.193.132.0/2257.193.132.1 to 57.193.135.25457.193.135.2551,022
9957.193.136.0/2257.193.136.1 to 57.193.139.25457.193.139.2551,022
10057.193.140.0/2257.193.140.1 to 57.193.143.25457.193.143.2551,022
10157.193.144.0/2257.193.144.1 to 57.193.147.25457.193.147.2551,022
10257.193.148.0/2257.193.148.1 to 57.193.151.25457.193.151.2551,022
10357.193.152.0/2257.193.152.1 to 57.193.155.25457.193.155.2551,022
10457.193.156.0/2257.193.156.1 to 57.193.159.25457.193.159.2551,022
10557.193.160.0/2257.193.160.1 to 57.193.163.25457.193.163.2551,022
10657.193.164.0/2257.193.164.1 to 57.193.167.25457.193.167.2551,022
10757.193.168.0/2257.193.168.1 to 57.193.171.25457.193.171.2551,022
10857.193.172.0/2257.193.172.1 to 57.193.175.25457.193.175.2551,022
10957.193.176.0/2257.193.176.1 to 57.193.179.25457.193.179.2551,022
11057.193.180.0/2257.193.180.1 to 57.193.183.25457.193.183.2551,022
11157.193.184.0/2257.193.184.1 to 57.193.187.25457.193.187.2551,022
11257.193.188.0/2257.193.188.1 to 57.193.191.25457.193.191.2551,022
11357.193.192.0/2257.193.192.1 to 57.193.195.25457.193.195.2551,022
11457.193.196.0/2257.193.196.1 to 57.193.199.25457.193.199.2551,022
11557.193.200.0/2257.193.200.1 to 57.193.203.25457.193.203.2551,022
11657.193.204.0/2257.193.204.1 to 57.193.207.25457.193.207.2551,022
11757.193.208.0/2257.193.208.1 to 57.193.211.25457.193.211.2551,022
11857.193.212.0/2257.193.212.1 to 57.193.215.25457.193.215.2551,022
11957.193.216.0/2257.193.216.1 to 57.193.219.25457.193.219.2551,022
12057.193.220.0/2257.193.220.1 to 57.193.223.25457.193.223.2551,022
12157.193.224.0/2257.193.224.1 to 57.193.227.25457.193.227.2551,022
12257.193.228.0/2257.193.228.1 to 57.193.231.25457.193.231.2551,022
12357.193.232.0/2257.193.232.1 to 57.193.235.25457.193.235.2551,022
12457.193.236.0/2257.193.236.1 to 57.193.239.25457.193.239.2551,022
12557.193.240.0/2257.193.240.1 to 57.193.243.25457.193.243.2551,022
12657.193.244.0/2257.193.244.1 to 57.193.247.25457.193.247.2551,022
12757.193.248.0/2257.193.248.1 to 57.193.251.25457.193.251.2551,022
12857.193.252.0/2257.193.252.1 to 57.193.255.25457.193.255.2551,022
12957.194.0.0/2257.194.0.1 to 57.194.3.25457.194.3.2551,022
13057.194.4.0/2257.194.4.1 to 57.194.7.25457.194.7.2551,022
13157.194.8.0/2257.194.8.1 to 57.194.11.25457.194.11.2551,022
13257.194.12.0/2257.194.12.1 to 57.194.15.25457.194.15.2551,022
13357.194.16.0/2257.194.16.1 to 57.194.19.25457.194.19.2551,022
13457.194.20.0/2257.194.20.1 to 57.194.23.25457.194.23.2551,022
13557.194.24.0/2257.194.24.1 to 57.194.27.25457.194.27.2551,022
13657.194.28.0/2257.194.28.1 to 57.194.31.25457.194.31.2551,022
13757.194.32.0/2257.194.32.1 to 57.194.35.25457.194.35.2551,022
13857.194.36.0/2257.194.36.1 to 57.194.39.25457.194.39.2551,022
13957.194.40.0/2257.194.40.1 to 57.194.43.25457.194.43.2551,022
14057.194.44.0/2257.194.44.1 to 57.194.47.25457.194.47.2551,022
14157.194.48.0/2257.194.48.1 to 57.194.51.25457.194.51.2551,022
14257.194.52.0/2257.194.52.1 to 57.194.55.25457.194.55.2551,022
14357.194.56.0/2257.194.56.1 to 57.194.59.25457.194.59.2551,022
14457.194.60.0/2257.194.60.1 to 57.194.63.25457.194.63.2551,022
14557.194.64.0/2257.194.64.1 to 57.194.67.25457.194.67.2551,022
14657.194.68.0/2257.194.68.1 to 57.194.71.25457.194.71.2551,022
14757.194.72.0/2257.194.72.1 to 57.194.75.25457.194.75.2551,022
14857.194.76.0/2257.194.76.1 to 57.194.79.25457.194.79.2551,022
14957.194.80.0/2257.194.80.1 to 57.194.83.25457.194.83.2551,022
15057.194.84.0/2257.194.84.1 to 57.194.87.25457.194.87.2551,022
15157.194.88.0/2257.194.88.1 to 57.194.91.25457.194.91.2551,022
15257.194.92.0/2257.194.92.1 to 57.194.95.25457.194.95.2551,022
15357.194.96.0/2257.194.96.1 to 57.194.99.25457.194.99.2551,022
15457.194.100.0/2257.194.100.1 to 57.194.103.25457.194.103.2551,022
15557.194.104.0/2257.194.104.1 to 57.194.107.25457.194.107.2551,022
15657.194.108.0/2257.194.108.1 to 57.194.111.25457.194.111.2551,022
15757.194.112.0/2257.194.112.1 to 57.194.115.25457.194.115.2551,022
15857.194.116.0/2257.194.116.1 to 57.194.119.25457.194.119.2551,022
15957.194.120.0/2257.194.120.1 to 57.194.123.25457.194.123.2551,022
16057.194.124.0/2257.194.124.1 to 57.194.127.25457.194.127.2551,022
16157.194.128.0/2257.194.128.1 to 57.194.131.25457.194.131.2551,022
16257.194.132.0/2257.194.132.1 to 57.194.135.25457.194.135.2551,022
16357.194.136.0/2257.194.136.1 to 57.194.139.25457.194.139.2551,022
16457.194.140.0/2257.194.140.1 to 57.194.143.25457.194.143.2551,022
16557.194.144.0/2257.194.144.1 to 57.194.147.25457.194.147.2551,022
16657.194.148.0/2257.194.148.1 to 57.194.151.25457.194.151.2551,022
16757.194.152.0/2257.194.152.1 to 57.194.155.25457.194.155.2551,022
16857.194.156.0/2257.194.156.1 to 57.194.159.25457.194.159.2551,022
16957.194.160.0/2257.194.160.1 to 57.194.163.25457.194.163.2551,022
17057.194.164.0/2257.194.164.1 to 57.194.167.25457.194.167.2551,022
17157.194.168.0/2257.194.168.1 to 57.194.171.25457.194.171.2551,022
17257.194.172.0/2257.194.172.1 to 57.194.175.25457.194.175.2551,022
17357.194.176.0/2257.194.176.1 to 57.194.179.25457.194.179.2551,022
17457.194.180.0/2257.194.180.1 to 57.194.183.25457.194.183.2551,022
17557.194.184.0/2257.194.184.1 to 57.194.187.25457.194.187.2551,022
17657.194.188.0/2257.194.188.1 to 57.194.191.25457.194.191.2551,022
17757.194.192.0/2257.194.192.1 to 57.194.195.25457.194.195.2551,022
17857.194.196.0/2257.194.196.1 to 57.194.199.25457.194.199.2551,022
17957.194.200.0/2257.194.200.1 to 57.194.203.25457.194.203.2551,022
18057.194.204.0/2257.194.204.1 to 57.194.207.25457.194.207.2551,022
18157.194.208.0/2257.194.208.1 to 57.194.211.25457.194.211.2551,022
18257.194.212.0/2257.194.212.1 to 57.194.215.25457.194.215.2551,022
18357.194.216.0/2257.194.216.1 to 57.194.219.25457.194.219.2551,022
18457.194.220.0/2257.194.220.1 to 57.194.223.25457.194.223.2551,022
18557.194.224.0/2257.194.224.1 to 57.194.227.25457.194.227.2551,022
18657.194.228.0/2257.194.228.1 to 57.194.231.25457.194.231.2551,022
18757.194.232.0/2257.194.232.1 to 57.194.235.25457.194.235.2551,022
18857.194.236.0/2257.194.236.1 to 57.194.239.25457.194.239.2551,022
18957.194.240.0/2257.194.240.1 to 57.194.243.25457.194.243.2551,022
19057.194.244.0/2257.194.244.1 to 57.194.247.25457.194.247.2551,022
19157.194.248.0/2257.194.248.1 to 57.194.251.25457.194.251.2551,022
19257.194.252.0/2257.194.252.1 to 57.194.255.25457.194.255.2551,022
19357.195.0.0/2257.195.0.1 to 57.195.3.25457.195.3.2551,022
19457.195.4.0/2257.195.4.1 to 57.195.7.25457.195.7.2551,022
19557.195.8.0/2257.195.8.1 to 57.195.11.25457.195.11.2551,022
19657.195.12.0/2257.195.12.1 to 57.195.15.25457.195.15.2551,022
19757.195.16.0/2257.195.16.1 to 57.195.19.25457.195.19.2551,022
19857.195.20.0/2257.195.20.1 to 57.195.23.25457.195.23.2551,022
19957.195.24.0/2257.195.24.1 to 57.195.27.25457.195.27.2551,022
20057.195.28.0/2257.195.28.1 to 57.195.31.25457.195.31.2551,022
20157.195.32.0/2257.195.32.1 to 57.195.35.25457.195.35.2551,022
20257.195.36.0/2257.195.36.1 to 57.195.39.25457.195.39.2551,022
20357.195.40.0/2257.195.40.1 to 57.195.43.25457.195.43.2551,022
20457.195.44.0/2257.195.44.1 to 57.195.47.25457.195.47.2551,022
20557.195.48.0/2257.195.48.1 to 57.195.51.25457.195.51.2551,022
20657.195.52.0/2257.195.52.1 to 57.195.55.25457.195.55.2551,022
20757.195.56.0/2257.195.56.1 to 57.195.59.25457.195.59.2551,022
20857.195.60.0/2257.195.60.1 to 57.195.63.25457.195.63.2551,022
20957.195.64.0/2257.195.64.1 to 57.195.67.25457.195.67.2551,022
21057.195.68.0/2257.195.68.1 to 57.195.71.25457.195.71.2551,022
21157.195.72.0/2257.195.72.1 to 57.195.75.25457.195.75.2551,022
21257.195.76.0/2257.195.76.1 to 57.195.79.25457.195.79.2551,022
21357.195.80.0/2257.195.80.1 to 57.195.83.25457.195.83.2551,022
21457.195.84.0/2257.195.84.1 to 57.195.87.25457.195.87.2551,022
21557.195.88.0/2257.195.88.1 to 57.195.91.25457.195.91.2551,022
21657.195.92.0/2257.195.92.1 to 57.195.95.25457.195.95.2551,022
21757.195.96.0/2257.195.96.1 to 57.195.99.25457.195.99.2551,022
21857.195.100.0/2257.195.100.1 to 57.195.103.25457.195.103.2551,022
21957.195.104.0/2257.195.104.1 to 57.195.107.25457.195.107.2551,022
22057.195.108.0/2257.195.108.1 to 57.195.111.25457.195.111.2551,022
22157.195.112.0/2257.195.112.1 to 57.195.115.25457.195.115.2551,022
22257.195.116.0/2257.195.116.1 to 57.195.119.25457.195.119.2551,022
22357.195.120.0/2257.195.120.1 to 57.195.123.25457.195.123.2551,022
22457.195.124.0/2257.195.124.1 to 57.195.127.25457.195.127.2551,022
22557.195.128.0/2257.195.128.1 to 57.195.131.25457.195.131.2551,022
22657.195.132.0/2257.195.132.1 to 57.195.135.25457.195.135.2551,022
22757.195.136.0/2257.195.136.1 to 57.195.139.25457.195.139.2551,022
22857.195.140.0/2257.195.140.1 to 57.195.143.25457.195.143.2551,022
22957.195.144.0/2257.195.144.1 to 57.195.147.25457.195.147.2551,022
23057.195.148.0/2257.195.148.1 to 57.195.151.25457.195.151.2551,022
23157.195.152.0/2257.195.152.1 to 57.195.155.25457.195.155.2551,022
23257.195.156.0/2257.195.156.1 to 57.195.159.25457.195.159.2551,022
23357.195.160.0/2257.195.160.1 to 57.195.163.25457.195.163.2551,022
23457.195.164.0/2257.195.164.1 to 57.195.167.25457.195.167.2551,022
23557.195.168.0/2257.195.168.1 to 57.195.171.25457.195.171.2551,022
23657.195.172.0/2257.195.172.1 to 57.195.175.25457.195.175.2551,022
23757.195.176.0/2257.195.176.1 to 57.195.179.25457.195.179.2551,022
23857.195.180.0/2257.195.180.1 to 57.195.183.25457.195.183.2551,022
23957.195.184.0/2257.195.184.1 to 57.195.187.25457.195.187.2551,022
24057.195.188.0/2257.195.188.1 to 57.195.191.25457.195.191.2551,022
24157.195.192.0/2257.195.192.1 to 57.195.195.25457.195.195.2551,022
24257.195.196.0/2257.195.196.1 to 57.195.199.25457.195.199.2551,022
24357.195.200.0/2257.195.200.1 to 57.195.203.25457.195.203.2551,022
24457.195.204.0/2257.195.204.1 to 57.195.207.25457.195.207.2551,022
24557.195.208.0/2257.195.208.1 to 57.195.211.25457.195.211.2551,022
24657.195.212.0/2257.195.212.1 to 57.195.215.25457.195.215.2551,022
24757.195.216.0/2257.195.216.1 to 57.195.219.25457.195.219.2551,022
24857.195.220.0/2257.195.220.1 to 57.195.223.25457.195.223.2551,022
24957.195.224.0/2257.195.224.1 to 57.195.227.25457.195.227.2551,022
25057.195.228.0/2257.195.228.1 to 57.195.231.25457.195.231.2551,022
25157.195.232.0/2257.195.232.1 to 57.195.235.25457.195.235.2551,022
25257.195.236.0/2257.195.236.1 to 57.195.239.25457.195.239.2551,022
25357.195.240.0/2257.195.240.1 to 57.195.243.25457.195.243.2551,022
25457.195.244.0/2257.195.244.1 to 57.195.247.25457.195.247.2551,022
25557.195.248.0/2257.195.248.1 to 57.195.251.25457.195.251.2551,022
25657.195.252.0/2257.195.252.1 to 57.195.255.25457.195.255.2551,022

IPv4 CIDR reference (/0 to /32)

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

IPv6 prefix reference

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

Private and special ranges

IPv4

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

IPv6

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

About this tool

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

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

Common questions

Why are two addresses lost in every IPv4 subnet?

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

What size of IPv6 network should a LAN use?

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

What is a wildcard mask?

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

Which ranges can I use inside an office?

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