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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.

Network61.64.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
61.64.0.0
Broadcast address
61.127.255.255
First usable
61.64.0.1
Last usable
61.127.255.254
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 3D400000 · Integer 1027604480 to 1031798783
Reverse DNS zones
64.61.in-addr.arpa
65.61.in-addr.arpa
66.61.in-addr.arpa
67.61.in-addr.arpa
68.61.in-addr.arpa
69.61.in-addr.arpa
70.61.in-addr.arpa
71.61.in-addr.arpa
72.61.in-addr.arpa
73.61.in-addr.arpa
74.61.in-addr.arpa
75.61.in-addr.arpa
76.61.in-addr.arpa
77.61.in-addr.arpa
78.61.in-addr.arpa
79.61.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
Address00111101.01000000.00000000.0000000061.64.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00111101.01000000.00000000.0000000061.64.0.0
Broadcast00111101.01111111.11111111.1111111161.127.255.255
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)

61.64.0.0/10 makes 4,096 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
161.64.0.0/2261.64.0.1 to 61.64.3.25461.64.3.2551,022
261.64.4.0/2261.64.4.1 to 61.64.7.25461.64.7.2551,022
361.64.8.0/2261.64.8.1 to 61.64.11.25461.64.11.2551,022
461.64.12.0/2261.64.12.1 to 61.64.15.25461.64.15.2551,022
561.64.16.0/2261.64.16.1 to 61.64.19.25461.64.19.2551,022
661.64.20.0/2261.64.20.1 to 61.64.23.25461.64.23.2551,022
761.64.24.0/2261.64.24.1 to 61.64.27.25461.64.27.2551,022
861.64.28.0/2261.64.28.1 to 61.64.31.25461.64.31.2551,022
961.64.32.0/2261.64.32.1 to 61.64.35.25461.64.35.2551,022
1061.64.36.0/2261.64.36.1 to 61.64.39.25461.64.39.2551,022
1161.64.40.0/2261.64.40.1 to 61.64.43.25461.64.43.2551,022
1261.64.44.0/2261.64.44.1 to 61.64.47.25461.64.47.2551,022
1361.64.48.0/2261.64.48.1 to 61.64.51.25461.64.51.2551,022
1461.64.52.0/2261.64.52.1 to 61.64.55.25461.64.55.2551,022
1561.64.56.0/2261.64.56.1 to 61.64.59.25461.64.59.2551,022
1661.64.60.0/2261.64.60.1 to 61.64.63.25461.64.63.2551,022
1761.64.64.0/2261.64.64.1 to 61.64.67.25461.64.67.2551,022
1861.64.68.0/2261.64.68.1 to 61.64.71.25461.64.71.2551,022
1961.64.72.0/2261.64.72.1 to 61.64.75.25461.64.75.2551,022
2061.64.76.0/2261.64.76.1 to 61.64.79.25461.64.79.2551,022
2161.64.80.0/2261.64.80.1 to 61.64.83.25461.64.83.2551,022
2261.64.84.0/2261.64.84.1 to 61.64.87.25461.64.87.2551,022
2361.64.88.0/2261.64.88.1 to 61.64.91.25461.64.91.2551,022
2461.64.92.0/2261.64.92.1 to 61.64.95.25461.64.95.2551,022
2561.64.96.0/2261.64.96.1 to 61.64.99.25461.64.99.2551,022
2661.64.100.0/2261.64.100.1 to 61.64.103.25461.64.103.2551,022
2761.64.104.0/2261.64.104.1 to 61.64.107.25461.64.107.2551,022
2861.64.108.0/2261.64.108.1 to 61.64.111.25461.64.111.2551,022
2961.64.112.0/2261.64.112.1 to 61.64.115.25461.64.115.2551,022
3061.64.116.0/2261.64.116.1 to 61.64.119.25461.64.119.2551,022
3161.64.120.0/2261.64.120.1 to 61.64.123.25461.64.123.2551,022
3261.64.124.0/2261.64.124.1 to 61.64.127.25461.64.127.2551,022
3361.64.128.0/2261.64.128.1 to 61.64.131.25461.64.131.2551,022
3461.64.132.0/2261.64.132.1 to 61.64.135.25461.64.135.2551,022
3561.64.136.0/2261.64.136.1 to 61.64.139.25461.64.139.2551,022
3661.64.140.0/2261.64.140.1 to 61.64.143.25461.64.143.2551,022
3761.64.144.0/2261.64.144.1 to 61.64.147.25461.64.147.2551,022
3861.64.148.0/2261.64.148.1 to 61.64.151.25461.64.151.2551,022
3961.64.152.0/2261.64.152.1 to 61.64.155.25461.64.155.2551,022
4061.64.156.0/2261.64.156.1 to 61.64.159.25461.64.159.2551,022
4161.64.160.0/2261.64.160.1 to 61.64.163.25461.64.163.2551,022
4261.64.164.0/2261.64.164.1 to 61.64.167.25461.64.167.2551,022
4361.64.168.0/2261.64.168.1 to 61.64.171.25461.64.171.2551,022
4461.64.172.0/2261.64.172.1 to 61.64.175.25461.64.175.2551,022
4561.64.176.0/2261.64.176.1 to 61.64.179.25461.64.179.2551,022
4661.64.180.0/2261.64.180.1 to 61.64.183.25461.64.183.2551,022
4761.64.184.0/2261.64.184.1 to 61.64.187.25461.64.187.2551,022
4861.64.188.0/2261.64.188.1 to 61.64.191.25461.64.191.2551,022
4961.64.192.0/2261.64.192.1 to 61.64.195.25461.64.195.2551,022
5061.64.196.0/2261.64.196.1 to 61.64.199.25461.64.199.2551,022
5161.64.200.0/2261.64.200.1 to 61.64.203.25461.64.203.2551,022
5261.64.204.0/2261.64.204.1 to 61.64.207.25461.64.207.2551,022
5361.64.208.0/2261.64.208.1 to 61.64.211.25461.64.211.2551,022
5461.64.212.0/2261.64.212.1 to 61.64.215.25461.64.215.2551,022
5561.64.216.0/2261.64.216.1 to 61.64.219.25461.64.219.2551,022
5661.64.220.0/2261.64.220.1 to 61.64.223.25461.64.223.2551,022
5761.64.224.0/2261.64.224.1 to 61.64.227.25461.64.227.2551,022
5861.64.228.0/2261.64.228.1 to 61.64.231.25461.64.231.2551,022
5961.64.232.0/2261.64.232.1 to 61.64.235.25461.64.235.2551,022
6061.64.236.0/2261.64.236.1 to 61.64.239.25461.64.239.2551,022
6161.64.240.0/2261.64.240.1 to 61.64.243.25461.64.243.2551,022
6261.64.244.0/2261.64.244.1 to 61.64.247.25461.64.247.2551,022
6361.64.248.0/2261.64.248.1 to 61.64.251.25461.64.251.2551,022
6461.64.252.0/2261.64.252.1 to 61.64.255.25461.64.255.2551,022
6561.65.0.0/2261.65.0.1 to 61.65.3.25461.65.3.2551,022
6661.65.4.0/2261.65.4.1 to 61.65.7.25461.65.7.2551,022
6761.65.8.0/2261.65.8.1 to 61.65.11.25461.65.11.2551,022
6861.65.12.0/2261.65.12.1 to 61.65.15.25461.65.15.2551,022
6961.65.16.0/2261.65.16.1 to 61.65.19.25461.65.19.2551,022
7061.65.20.0/2261.65.20.1 to 61.65.23.25461.65.23.2551,022
7161.65.24.0/2261.65.24.1 to 61.65.27.25461.65.27.2551,022
7261.65.28.0/2261.65.28.1 to 61.65.31.25461.65.31.2551,022
7361.65.32.0/2261.65.32.1 to 61.65.35.25461.65.35.2551,022
7461.65.36.0/2261.65.36.1 to 61.65.39.25461.65.39.2551,022
7561.65.40.0/2261.65.40.1 to 61.65.43.25461.65.43.2551,022
7661.65.44.0/2261.65.44.1 to 61.65.47.25461.65.47.2551,022
7761.65.48.0/2261.65.48.1 to 61.65.51.25461.65.51.2551,022
7861.65.52.0/2261.65.52.1 to 61.65.55.25461.65.55.2551,022
7961.65.56.0/2261.65.56.1 to 61.65.59.25461.65.59.2551,022
8061.65.60.0/2261.65.60.1 to 61.65.63.25461.65.63.2551,022
8161.65.64.0/2261.65.64.1 to 61.65.67.25461.65.67.2551,022
8261.65.68.0/2261.65.68.1 to 61.65.71.25461.65.71.2551,022
8361.65.72.0/2261.65.72.1 to 61.65.75.25461.65.75.2551,022
8461.65.76.0/2261.65.76.1 to 61.65.79.25461.65.79.2551,022
8561.65.80.0/2261.65.80.1 to 61.65.83.25461.65.83.2551,022
8661.65.84.0/2261.65.84.1 to 61.65.87.25461.65.87.2551,022
8761.65.88.0/2261.65.88.1 to 61.65.91.25461.65.91.2551,022
8861.65.92.0/2261.65.92.1 to 61.65.95.25461.65.95.2551,022
8961.65.96.0/2261.65.96.1 to 61.65.99.25461.65.99.2551,022
9061.65.100.0/2261.65.100.1 to 61.65.103.25461.65.103.2551,022
9161.65.104.0/2261.65.104.1 to 61.65.107.25461.65.107.2551,022
9261.65.108.0/2261.65.108.1 to 61.65.111.25461.65.111.2551,022
9361.65.112.0/2261.65.112.1 to 61.65.115.25461.65.115.2551,022
9461.65.116.0/2261.65.116.1 to 61.65.119.25461.65.119.2551,022
9561.65.120.0/2261.65.120.1 to 61.65.123.25461.65.123.2551,022
9661.65.124.0/2261.65.124.1 to 61.65.127.25461.65.127.2551,022
9761.65.128.0/2261.65.128.1 to 61.65.131.25461.65.131.2551,022
9861.65.132.0/2261.65.132.1 to 61.65.135.25461.65.135.2551,022
9961.65.136.0/2261.65.136.1 to 61.65.139.25461.65.139.2551,022
10061.65.140.0/2261.65.140.1 to 61.65.143.25461.65.143.2551,022
10161.65.144.0/2261.65.144.1 to 61.65.147.25461.65.147.2551,022
10261.65.148.0/2261.65.148.1 to 61.65.151.25461.65.151.2551,022
10361.65.152.0/2261.65.152.1 to 61.65.155.25461.65.155.2551,022
10461.65.156.0/2261.65.156.1 to 61.65.159.25461.65.159.2551,022
10561.65.160.0/2261.65.160.1 to 61.65.163.25461.65.163.2551,022
10661.65.164.0/2261.65.164.1 to 61.65.167.25461.65.167.2551,022
10761.65.168.0/2261.65.168.1 to 61.65.171.25461.65.171.2551,022
10861.65.172.0/2261.65.172.1 to 61.65.175.25461.65.175.2551,022
10961.65.176.0/2261.65.176.1 to 61.65.179.25461.65.179.2551,022
11061.65.180.0/2261.65.180.1 to 61.65.183.25461.65.183.2551,022
11161.65.184.0/2261.65.184.1 to 61.65.187.25461.65.187.2551,022
11261.65.188.0/2261.65.188.1 to 61.65.191.25461.65.191.2551,022
11361.65.192.0/2261.65.192.1 to 61.65.195.25461.65.195.2551,022
11461.65.196.0/2261.65.196.1 to 61.65.199.25461.65.199.2551,022
11561.65.200.0/2261.65.200.1 to 61.65.203.25461.65.203.2551,022
11661.65.204.0/2261.65.204.1 to 61.65.207.25461.65.207.2551,022
11761.65.208.0/2261.65.208.1 to 61.65.211.25461.65.211.2551,022
11861.65.212.0/2261.65.212.1 to 61.65.215.25461.65.215.2551,022
11961.65.216.0/2261.65.216.1 to 61.65.219.25461.65.219.2551,022
12061.65.220.0/2261.65.220.1 to 61.65.223.25461.65.223.2551,022
12161.65.224.0/2261.65.224.1 to 61.65.227.25461.65.227.2551,022
12261.65.228.0/2261.65.228.1 to 61.65.231.25461.65.231.2551,022
12361.65.232.0/2261.65.232.1 to 61.65.235.25461.65.235.2551,022
12461.65.236.0/2261.65.236.1 to 61.65.239.25461.65.239.2551,022
12561.65.240.0/2261.65.240.1 to 61.65.243.25461.65.243.2551,022
12661.65.244.0/2261.65.244.1 to 61.65.247.25461.65.247.2551,022
12761.65.248.0/2261.65.248.1 to 61.65.251.25461.65.251.2551,022
12861.65.252.0/2261.65.252.1 to 61.65.255.25461.65.255.2551,022
12961.66.0.0/2261.66.0.1 to 61.66.3.25461.66.3.2551,022
13061.66.4.0/2261.66.4.1 to 61.66.7.25461.66.7.2551,022
13161.66.8.0/2261.66.8.1 to 61.66.11.25461.66.11.2551,022
13261.66.12.0/2261.66.12.1 to 61.66.15.25461.66.15.2551,022
13361.66.16.0/2261.66.16.1 to 61.66.19.25461.66.19.2551,022
13461.66.20.0/2261.66.20.1 to 61.66.23.25461.66.23.2551,022
13561.66.24.0/2261.66.24.1 to 61.66.27.25461.66.27.2551,022
13661.66.28.0/2261.66.28.1 to 61.66.31.25461.66.31.2551,022
13761.66.32.0/2261.66.32.1 to 61.66.35.25461.66.35.2551,022
13861.66.36.0/2261.66.36.1 to 61.66.39.25461.66.39.2551,022
13961.66.40.0/2261.66.40.1 to 61.66.43.25461.66.43.2551,022
14061.66.44.0/2261.66.44.1 to 61.66.47.25461.66.47.2551,022
14161.66.48.0/2261.66.48.1 to 61.66.51.25461.66.51.2551,022
14261.66.52.0/2261.66.52.1 to 61.66.55.25461.66.55.2551,022
14361.66.56.0/2261.66.56.1 to 61.66.59.25461.66.59.2551,022
14461.66.60.0/2261.66.60.1 to 61.66.63.25461.66.63.2551,022
14561.66.64.0/2261.66.64.1 to 61.66.67.25461.66.67.2551,022
14661.66.68.0/2261.66.68.1 to 61.66.71.25461.66.71.2551,022
14761.66.72.0/2261.66.72.1 to 61.66.75.25461.66.75.2551,022
14861.66.76.0/2261.66.76.1 to 61.66.79.25461.66.79.2551,022
14961.66.80.0/2261.66.80.1 to 61.66.83.25461.66.83.2551,022
15061.66.84.0/2261.66.84.1 to 61.66.87.25461.66.87.2551,022
15161.66.88.0/2261.66.88.1 to 61.66.91.25461.66.91.2551,022
15261.66.92.0/2261.66.92.1 to 61.66.95.25461.66.95.2551,022
15361.66.96.0/2261.66.96.1 to 61.66.99.25461.66.99.2551,022
15461.66.100.0/2261.66.100.1 to 61.66.103.25461.66.103.2551,022
15561.66.104.0/2261.66.104.1 to 61.66.107.25461.66.107.2551,022
15661.66.108.0/2261.66.108.1 to 61.66.111.25461.66.111.2551,022
15761.66.112.0/2261.66.112.1 to 61.66.115.25461.66.115.2551,022
15861.66.116.0/2261.66.116.1 to 61.66.119.25461.66.119.2551,022
15961.66.120.0/2261.66.120.1 to 61.66.123.25461.66.123.2551,022
16061.66.124.0/2261.66.124.1 to 61.66.127.25461.66.127.2551,022
16161.66.128.0/2261.66.128.1 to 61.66.131.25461.66.131.2551,022
16261.66.132.0/2261.66.132.1 to 61.66.135.25461.66.135.2551,022
16361.66.136.0/2261.66.136.1 to 61.66.139.25461.66.139.2551,022
16461.66.140.0/2261.66.140.1 to 61.66.143.25461.66.143.2551,022
16561.66.144.0/2261.66.144.1 to 61.66.147.25461.66.147.2551,022
16661.66.148.0/2261.66.148.1 to 61.66.151.25461.66.151.2551,022
16761.66.152.0/2261.66.152.1 to 61.66.155.25461.66.155.2551,022
16861.66.156.0/2261.66.156.1 to 61.66.159.25461.66.159.2551,022
16961.66.160.0/2261.66.160.1 to 61.66.163.25461.66.163.2551,022
17061.66.164.0/2261.66.164.1 to 61.66.167.25461.66.167.2551,022
17161.66.168.0/2261.66.168.1 to 61.66.171.25461.66.171.2551,022
17261.66.172.0/2261.66.172.1 to 61.66.175.25461.66.175.2551,022
17361.66.176.0/2261.66.176.1 to 61.66.179.25461.66.179.2551,022
17461.66.180.0/2261.66.180.1 to 61.66.183.25461.66.183.2551,022
17561.66.184.0/2261.66.184.1 to 61.66.187.25461.66.187.2551,022
17661.66.188.0/2261.66.188.1 to 61.66.191.25461.66.191.2551,022
17761.66.192.0/2261.66.192.1 to 61.66.195.25461.66.195.2551,022
17861.66.196.0/2261.66.196.1 to 61.66.199.25461.66.199.2551,022
17961.66.200.0/2261.66.200.1 to 61.66.203.25461.66.203.2551,022
18061.66.204.0/2261.66.204.1 to 61.66.207.25461.66.207.2551,022
18161.66.208.0/2261.66.208.1 to 61.66.211.25461.66.211.2551,022
18261.66.212.0/2261.66.212.1 to 61.66.215.25461.66.215.2551,022
18361.66.216.0/2261.66.216.1 to 61.66.219.25461.66.219.2551,022
18461.66.220.0/2261.66.220.1 to 61.66.223.25461.66.223.2551,022
18561.66.224.0/2261.66.224.1 to 61.66.227.25461.66.227.2551,022
18661.66.228.0/2261.66.228.1 to 61.66.231.25461.66.231.2551,022
18761.66.232.0/2261.66.232.1 to 61.66.235.25461.66.235.2551,022
18861.66.236.0/2261.66.236.1 to 61.66.239.25461.66.239.2551,022
18961.66.240.0/2261.66.240.1 to 61.66.243.25461.66.243.2551,022
19061.66.244.0/2261.66.244.1 to 61.66.247.25461.66.247.2551,022
19161.66.248.0/2261.66.248.1 to 61.66.251.25461.66.251.2551,022
19261.66.252.0/2261.66.252.1 to 61.66.255.25461.66.255.2551,022
19361.67.0.0/2261.67.0.1 to 61.67.3.25461.67.3.2551,022
19461.67.4.0/2261.67.4.1 to 61.67.7.25461.67.7.2551,022
19561.67.8.0/2261.67.8.1 to 61.67.11.25461.67.11.2551,022
19661.67.12.0/2261.67.12.1 to 61.67.15.25461.67.15.2551,022
19761.67.16.0/2261.67.16.1 to 61.67.19.25461.67.19.2551,022
19861.67.20.0/2261.67.20.1 to 61.67.23.25461.67.23.2551,022
19961.67.24.0/2261.67.24.1 to 61.67.27.25461.67.27.2551,022
20061.67.28.0/2261.67.28.1 to 61.67.31.25461.67.31.2551,022
20161.67.32.0/2261.67.32.1 to 61.67.35.25461.67.35.2551,022
20261.67.36.0/2261.67.36.1 to 61.67.39.25461.67.39.2551,022
20361.67.40.0/2261.67.40.1 to 61.67.43.25461.67.43.2551,022
20461.67.44.0/2261.67.44.1 to 61.67.47.25461.67.47.2551,022
20561.67.48.0/2261.67.48.1 to 61.67.51.25461.67.51.2551,022
20661.67.52.0/2261.67.52.1 to 61.67.55.25461.67.55.2551,022
20761.67.56.0/2261.67.56.1 to 61.67.59.25461.67.59.2551,022
20861.67.60.0/2261.67.60.1 to 61.67.63.25461.67.63.2551,022
20961.67.64.0/2261.67.64.1 to 61.67.67.25461.67.67.2551,022
21061.67.68.0/2261.67.68.1 to 61.67.71.25461.67.71.2551,022
21161.67.72.0/2261.67.72.1 to 61.67.75.25461.67.75.2551,022
21261.67.76.0/2261.67.76.1 to 61.67.79.25461.67.79.2551,022
21361.67.80.0/2261.67.80.1 to 61.67.83.25461.67.83.2551,022
21461.67.84.0/2261.67.84.1 to 61.67.87.25461.67.87.2551,022
21561.67.88.0/2261.67.88.1 to 61.67.91.25461.67.91.2551,022
21661.67.92.0/2261.67.92.1 to 61.67.95.25461.67.95.2551,022
21761.67.96.0/2261.67.96.1 to 61.67.99.25461.67.99.2551,022
21861.67.100.0/2261.67.100.1 to 61.67.103.25461.67.103.2551,022
21961.67.104.0/2261.67.104.1 to 61.67.107.25461.67.107.2551,022
22061.67.108.0/2261.67.108.1 to 61.67.111.25461.67.111.2551,022
22161.67.112.0/2261.67.112.1 to 61.67.115.25461.67.115.2551,022
22261.67.116.0/2261.67.116.1 to 61.67.119.25461.67.119.2551,022
22361.67.120.0/2261.67.120.1 to 61.67.123.25461.67.123.2551,022
22461.67.124.0/2261.67.124.1 to 61.67.127.25461.67.127.2551,022
22561.67.128.0/2261.67.128.1 to 61.67.131.25461.67.131.2551,022
22661.67.132.0/2261.67.132.1 to 61.67.135.25461.67.135.2551,022
22761.67.136.0/2261.67.136.1 to 61.67.139.25461.67.139.2551,022
22861.67.140.0/2261.67.140.1 to 61.67.143.25461.67.143.2551,022
22961.67.144.0/2261.67.144.1 to 61.67.147.25461.67.147.2551,022
23061.67.148.0/2261.67.148.1 to 61.67.151.25461.67.151.2551,022
23161.67.152.0/2261.67.152.1 to 61.67.155.25461.67.155.2551,022
23261.67.156.0/2261.67.156.1 to 61.67.159.25461.67.159.2551,022
23361.67.160.0/2261.67.160.1 to 61.67.163.25461.67.163.2551,022
23461.67.164.0/2261.67.164.1 to 61.67.167.25461.67.167.2551,022
23561.67.168.0/2261.67.168.1 to 61.67.171.25461.67.171.2551,022
23661.67.172.0/2261.67.172.1 to 61.67.175.25461.67.175.2551,022
23761.67.176.0/2261.67.176.1 to 61.67.179.25461.67.179.2551,022
23861.67.180.0/2261.67.180.1 to 61.67.183.25461.67.183.2551,022
23961.67.184.0/2261.67.184.1 to 61.67.187.25461.67.187.2551,022
24061.67.188.0/2261.67.188.1 to 61.67.191.25461.67.191.2551,022
24161.67.192.0/2261.67.192.1 to 61.67.195.25461.67.195.2551,022
24261.67.196.0/2261.67.196.1 to 61.67.199.25461.67.199.2551,022
24361.67.200.0/2261.67.200.1 to 61.67.203.25461.67.203.2551,022
24461.67.204.0/2261.67.204.1 to 61.67.207.25461.67.207.2551,022
24561.67.208.0/2261.67.208.1 to 61.67.211.25461.67.211.2551,022
24661.67.212.0/2261.67.212.1 to 61.67.215.25461.67.215.2551,022
24761.67.216.0/2261.67.216.1 to 61.67.219.25461.67.219.2551,022
24861.67.220.0/2261.67.220.1 to 61.67.223.25461.67.223.2551,022
24961.67.224.0/2261.67.224.1 to 61.67.227.25461.67.227.2551,022
25061.67.228.0/2261.67.228.1 to 61.67.231.25461.67.231.2551,022
25161.67.232.0/2261.67.232.1 to 61.67.235.25461.67.235.2551,022
25261.67.236.0/2261.67.236.1 to 61.67.239.25461.67.239.2551,022
25361.67.240.0/2261.67.240.1 to 61.67.243.25461.67.243.2551,022
25461.67.244.0/2261.67.244.1 to 61.67.247.25461.67.247.2551,022
25561.67.248.0/2261.67.248.1 to 61.67.251.25461.67.251.2551,022
25661.67.252.0/2261.67.252.1 to 61.67.255.25461.67.255.2551,022

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.