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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.

Network29.160.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
29.160.0.0
Broadcast address
29.191.255.255
First usable
29.160.0.1
Last usable
29.191.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 1DA00000 · Integer 497025024 to 499122175
Reverse DNS zones
160.29.in-addr.arpa
161.29.in-addr.arpa
162.29.in-addr.arpa
163.29.in-addr.arpa
164.29.in-addr.arpa
165.29.in-addr.arpa
166.29.in-addr.arpa
167.29.in-addr.arpa
168.29.in-addr.arpa
169.29.in-addr.arpa
170.29.in-addr.arpa
171.29.in-addr.arpa
172.29.in-addr.arpa
173.29.in-addr.arpa
174.29.in-addr.arpa
175.29.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00011101.10100000.00000000.0000000029.160.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00011101.10100000.00000000.0000000029.160.0.0
Broadcast00011101.10111111.11111111.1111111129.191.255.255
Split into smaller subnets/20
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

29.160.0.0/11 makes 512 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
129.160.0.0/2029.160.0.1 to 29.160.15.25429.160.15.2554,094
229.160.16.0/2029.160.16.1 to 29.160.31.25429.160.31.2554,094
329.160.32.0/2029.160.32.1 to 29.160.47.25429.160.47.2554,094
429.160.48.0/2029.160.48.1 to 29.160.63.25429.160.63.2554,094
529.160.64.0/2029.160.64.1 to 29.160.79.25429.160.79.2554,094
629.160.80.0/2029.160.80.1 to 29.160.95.25429.160.95.2554,094
729.160.96.0/2029.160.96.1 to 29.160.111.25429.160.111.2554,094
829.160.112.0/2029.160.112.1 to 29.160.127.25429.160.127.2554,094
929.160.128.0/2029.160.128.1 to 29.160.143.25429.160.143.2554,094
1029.160.144.0/2029.160.144.1 to 29.160.159.25429.160.159.2554,094
1129.160.160.0/2029.160.160.1 to 29.160.175.25429.160.175.2554,094
1229.160.176.0/2029.160.176.1 to 29.160.191.25429.160.191.2554,094
1329.160.192.0/2029.160.192.1 to 29.160.207.25429.160.207.2554,094
1429.160.208.0/2029.160.208.1 to 29.160.223.25429.160.223.2554,094
1529.160.224.0/2029.160.224.1 to 29.160.239.25429.160.239.2554,094
1629.160.240.0/2029.160.240.1 to 29.160.255.25429.160.255.2554,094
1729.161.0.0/2029.161.0.1 to 29.161.15.25429.161.15.2554,094
1829.161.16.0/2029.161.16.1 to 29.161.31.25429.161.31.2554,094
1929.161.32.0/2029.161.32.1 to 29.161.47.25429.161.47.2554,094
2029.161.48.0/2029.161.48.1 to 29.161.63.25429.161.63.2554,094
2129.161.64.0/2029.161.64.1 to 29.161.79.25429.161.79.2554,094
2229.161.80.0/2029.161.80.1 to 29.161.95.25429.161.95.2554,094
2329.161.96.0/2029.161.96.1 to 29.161.111.25429.161.111.2554,094
2429.161.112.0/2029.161.112.1 to 29.161.127.25429.161.127.2554,094
2529.161.128.0/2029.161.128.1 to 29.161.143.25429.161.143.2554,094
2629.161.144.0/2029.161.144.1 to 29.161.159.25429.161.159.2554,094
2729.161.160.0/2029.161.160.1 to 29.161.175.25429.161.175.2554,094
2829.161.176.0/2029.161.176.1 to 29.161.191.25429.161.191.2554,094
2929.161.192.0/2029.161.192.1 to 29.161.207.25429.161.207.2554,094
3029.161.208.0/2029.161.208.1 to 29.161.223.25429.161.223.2554,094
3129.161.224.0/2029.161.224.1 to 29.161.239.25429.161.239.2554,094
3229.161.240.0/2029.161.240.1 to 29.161.255.25429.161.255.2554,094
3329.162.0.0/2029.162.0.1 to 29.162.15.25429.162.15.2554,094
3429.162.16.0/2029.162.16.1 to 29.162.31.25429.162.31.2554,094
3529.162.32.0/2029.162.32.1 to 29.162.47.25429.162.47.2554,094
3629.162.48.0/2029.162.48.1 to 29.162.63.25429.162.63.2554,094
3729.162.64.0/2029.162.64.1 to 29.162.79.25429.162.79.2554,094
3829.162.80.0/2029.162.80.1 to 29.162.95.25429.162.95.2554,094
3929.162.96.0/2029.162.96.1 to 29.162.111.25429.162.111.2554,094
4029.162.112.0/2029.162.112.1 to 29.162.127.25429.162.127.2554,094
4129.162.128.0/2029.162.128.1 to 29.162.143.25429.162.143.2554,094
4229.162.144.0/2029.162.144.1 to 29.162.159.25429.162.159.2554,094
4329.162.160.0/2029.162.160.1 to 29.162.175.25429.162.175.2554,094
4429.162.176.0/2029.162.176.1 to 29.162.191.25429.162.191.2554,094
4529.162.192.0/2029.162.192.1 to 29.162.207.25429.162.207.2554,094
4629.162.208.0/2029.162.208.1 to 29.162.223.25429.162.223.2554,094
4729.162.224.0/2029.162.224.1 to 29.162.239.25429.162.239.2554,094
4829.162.240.0/2029.162.240.1 to 29.162.255.25429.162.255.2554,094
4929.163.0.0/2029.163.0.1 to 29.163.15.25429.163.15.2554,094
5029.163.16.0/2029.163.16.1 to 29.163.31.25429.163.31.2554,094
5129.163.32.0/2029.163.32.1 to 29.163.47.25429.163.47.2554,094
5229.163.48.0/2029.163.48.1 to 29.163.63.25429.163.63.2554,094
5329.163.64.0/2029.163.64.1 to 29.163.79.25429.163.79.2554,094
5429.163.80.0/2029.163.80.1 to 29.163.95.25429.163.95.2554,094
5529.163.96.0/2029.163.96.1 to 29.163.111.25429.163.111.2554,094
5629.163.112.0/2029.163.112.1 to 29.163.127.25429.163.127.2554,094
5729.163.128.0/2029.163.128.1 to 29.163.143.25429.163.143.2554,094
5829.163.144.0/2029.163.144.1 to 29.163.159.25429.163.159.2554,094
5929.163.160.0/2029.163.160.1 to 29.163.175.25429.163.175.2554,094
6029.163.176.0/2029.163.176.1 to 29.163.191.25429.163.191.2554,094
6129.163.192.0/2029.163.192.1 to 29.163.207.25429.163.207.2554,094
6229.163.208.0/2029.163.208.1 to 29.163.223.25429.163.223.2554,094
6329.163.224.0/2029.163.224.1 to 29.163.239.25429.163.239.2554,094
6429.163.240.0/2029.163.240.1 to 29.163.255.25429.163.255.2554,094
6529.164.0.0/2029.164.0.1 to 29.164.15.25429.164.15.2554,094
6629.164.16.0/2029.164.16.1 to 29.164.31.25429.164.31.2554,094
6729.164.32.0/2029.164.32.1 to 29.164.47.25429.164.47.2554,094
6829.164.48.0/2029.164.48.1 to 29.164.63.25429.164.63.2554,094
6929.164.64.0/2029.164.64.1 to 29.164.79.25429.164.79.2554,094
7029.164.80.0/2029.164.80.1 to 29.164.95.25429.164.95.2554,094
7129.164.96.0/2029.164.96.1 to 29.164.111.25429.164.111.2554,094
7229.164.112.0/2029.164.112.1 to 29.164.127.25429.164.127.2554,094
7329.164.128.0/2029.164.128.1 to 29.164.143.25429.164.143.2554,094
7429.164.144.0/2029.164.144.1 to 29.164.159.25429.164.159.2554,094
7529.164.160.0/2029.164.160.1 to 29.164.175.25429.164.175.2554,094
7629.164.176.0/2029.164.176.1 to 29.164.191.25429.164.191.2554,094
7729.164.192.0/2029.164.192.1 to 29.164.207.25429.164.207.2554,094
7829.164.208.0/2029.164.208.1 to 29.164.223.25429.164.223.2554,094
7929.164.224.0/2029.164.224.1 to 29.164.239.25429.164.239.2554,094
8029.164.240.0/2029.164.240.1 to 29.164.255.25429.164.255.2554,094
8129.165.0.0/2029.165.0.1 to 29.165.15.25429.165.15.2554,094
8229.165.16.0/2029.165.16.1 to 29.165.31.25429.165.31.2554,094
8329.165.32.0/2029.165.32.1 to 29.165.47.25429.165.47.2554,094
8429.165.48.0/2029.165.48.1 to 29.165.63.25429.165.63.2554,094
8529.165.64.0/2029.165.64.1 to 29.165.79.25429.165.79.2554,094
8629.165.80.0/2029.165.80.1 to 29.165.95.25429.165.95.2554,094
8729.165.96.0/2029.165.96.1 to 29.165.111.25429.165.111.2554,094
8829.165.112.0/2029.165.112.1 to 29.165.127.25429.165.127.2554,094
8929.165.128.0/2029.165.128.1 to 29.165.143.25429.165.143.2554,094
9029.165.144.0/2029.165.144.1 to 29.165.159.25429.165.159.2554,094
9129.165.160.0/2029.165.160.1 to 29.165.175.25429.165.175.2554,094
9229.165.176.0/2029.165.176.1 to 29.165.191.25429.165.191.2554,094
9329.165.192.0/2029.165.192.1 to 29.165.207.25429.165.207.2554,094
9429.165.208.0/2029.165.208.1 to 29.165.223.25429.165.223.2554,094
9529.165.224.0/2029.165.224.1 to 29.165.239.25429.165.239.2554,094
9629.165.240.0/2029.165.240.1 to 29.165.255.25429.165.255.2554,094
9729.166.0.0/2029.166.0.1 to 29.166.15.25429.166.15.2554,094
9829.166.16.0/2029.166.16.1 to 29.166.31.25429.166.31.2554,094
9929.166.32.0/2029.166.32.1 to 29.166.47.25429.166.47.2554,094
10029.166.48.0/2029.166.48.1 to 29.166.63.25429.166.63.2554,094
10129.166.64.0/2029.166.64.1 to 29.166.79.25429.166.79.2554,094
10229.166.80.0/2029.166.80.1 to 29.166.95.25429.166.95.2554,094
10329.166.96.0/2029.166.96.1 to 29.166.111.25429.166.111.2554,094
10429.166.112.0/2029.166.112.1 to 29.166.127.25429.166.127.2554,094
10529.166.128.0/2029.166.128.1 to 29.166.143.25429.166.143.2554,094
10629.166.144.0/2029.166.144.1 to 29.166.159.25429.166.159.2554,094
10729.166.160.0/2029.166.160.1 to 29.166.175.25429.166.175.2554,094
10829.166.176.0/2029.166.176.1 to 29.166.191.25429.166.191.2554,094
10929.166.192.0/2029.166.192.1 to 29.166.207.25429.166.207.2554,094
11029.166.208.0/2029.166.208.1 to 29.166.223.25429.166.223.2554,094
11129.166.224.0/2029.166.224.1 to 29.166.239.25429.166.239.2554,094
11229.166.240.0/2029.166.240.1 to 29.166.255.25429.166.255.2554,094
11329.167.0.0/2029.167.0.1 to 29.167.15.25429.167.15.2554,094
11429.167.16.0/2029.167.16.1 to 29.167.31.25429.167.31.2554,094
11529.167.32.0/2029.167.32.1 to 29.167.47.25429.167.47.2554,094
11629.167.48.0/2029.167.48.1 to 29.167.63.25429.167.63.2554,094
11729.167.64.0/2029.167.64.1 to 29.167.79.25429.167.79.2554,094
11829.167.80.0/2029.167.80.1 to 29.167.95.25429.167.95.2554,094
11929.167.96.0/2029.167.96.1 to 29.167.111.25429.167.111.2554,094
12029.167.112.0/2029.167.112.1 to 29.167.127.25429.167.127.2554,094
12129.167.128.0/2029.167.128.1 to 29.167.143.25429.167.143.2554,094
12229.167.144.0/2029.167.144.1 to 29.167.159.25429.167.159.2554,094
12329.167.160.0/2029.167.160.1 to 29.167.175.25429.167.175.2554,094
12429.167.176.0/2029.167.176.1 to 29.167.191.25429.167.191.2554,094
12529.167.192.0/2029.167.192.1 to 29.167.207.25429.167.207.2554,094
12629.167.208.0/2029.167.208.1 to 29.167.223.25429.167.223.2554,094
12729.167.224.0/2029.167.224.1 to 29.167.239.25429.167.239.2554,094
12829.167.240.0/2029.167.240.1 to 29.167.255.25429.167.255.2554,094
12929.168.0.0/2029.168.0.1 to 29.168.15.25429.168.15.2554,094
13029.168.16.0/2029.168.16.1 to 29.168.31.25429.168.31.2554,094
13129.168.32.0/2029.168.32.1 to 29.168.47.25429.168.47.2554,094
13229.168.48.0/2029.168.48.1 to 29.168.63.25429.168.63.2554,094
13329.168.64.0/2029.168.64.1 to 29.168.79.25429.168.79.2554,094
13429.168.80.0/2029.168.80.1 to 29.168.95.25429.168.95.2554,094
13529.168.96.0/2029.168.96.1 to 29.168.111.25429.168.111.2554,094
13629.168.112.0/2029.168.112.1 to 29.168.127.25429.168.127.2554,094
13729.168.128.0/2029.168.128.1 to 29.168.143.25429.168.143.2554,094
13829.168.144.0/2029.168.144.1 to 29.168.159.25429.168.159.2554,094
13929.168.160.0/2029.168.160.1 to 29.168.175.25429.168.175.2554,094
14029.168.176.0/2029.168.176.1 to 29.168.191.25429.168.191.2554,094
14129.168.192.0/2029.168.192.1 to 29.168.207.25429.168.207.2554,094
14229.168.208.0/2029.168.208.1 to 29.168.223.25429.168.223.2554,094
14329.168.224.0/2029.168.224.1 to 29.168.239.25429.168.239.2554,094
14429.168.240.0/2029.168.240.1 to 29.168.255.25429.168.255.2554,094
14529.169.0.0/2029.169.0.1 to 29.169.15.25429.169.15.2554,094
14629.169.16.0/2029.169.16.1 to 29.169.31.25429.169.31.2554,094
14729.169.32.0/2029.169.32.1 to 29.169.47.25429.169.47.2554,094
14829.169.48.0/2029.169.48.1 to 29.169.63.25429.169.63.2554,094
14929.169.64.0/2029.169.64.1 to 29.169.79.25429.169.79.2554,094
15029.169.80.0/2029.169.80.1 to 29.169.95.25429.169.95.2554,094
15129.169.96.0/2029.169.96.1 to 29.169.111.25429.169.111.2554,094
15229.169.112.0/2029.169.112.1 to 29.169.127.25429.169.127.2554,094
15329.169.128.0/2029.169.128.1 to 29.169.143.25429.169.143.2554,094
15429.169.144.0/2029.169.144.1 to 29.169.159.25429.169.159.2554,094
15529.169.160.0/2029.169.160.1 to 29.169.175.25429.169.175.2554,094
15629.169.176.0/2029.169.176.1 to 29.169.191.25429.169.191.2554,094
15729.169.192.0/2029.169.192.1 to 29.169.207.25429.169.207.2554,094
15829.169.208.0/2029.169.208.1 to 29.169.223.25429.169.223.2554,094
15929.169.224.0/2029.169.224.1 to 29.169.239.25429.169.239.2554,094
16029.169.240.0/2029.169.240.1 to 29.169.255.25429.169.255.2554,094
16129.170.0.0/2029.170.0.1 to 29.170.15.25429.170.15.2554,094
16229.170.16.0/2029.170.16.1 to 29.170.31.25429.170.31.2554,094
16329.170.32.0/2029.170.32.1 to 29.170.47.25429.170.47.2554,094
16429.170.48.0/2029.170.48.1 to 29.170.63.25429.170.63.2554,094
16529.170.64.0/2029.170.64.1 to 29.170.79.25429.170.79.2554,094
16629.170.80.0/2029.170.80.1 to 29.170.95.25429.170.95.2554,094
16729.170.96.0/2029.170.96.1 to 29.170.111.25429.170.111.2554,094
16829.170.112.0/2029.170.112.1 to 29.170.127.25429.170.127.2554,094
16929.170.128.0/2029.170.128.1 to 29.170.143.25429.170.143.2554,094
17029.170.144.0/2029.170.144.1 to 29.170.159.25429.170.159.2554,094
17129.170.160.0/2029.170.160.1 to 29.170.175.25429.170.175.2554,094
17229.170.176.0/2029.170.176.1 to 29.170.191.25429.170.191.2554,094
17329.170.192.0/2029.170.192.1 to 29.170.207.25429.170.207.2554,094
17429.170.208.0/2029.170.208.1 to 29.170.223.25429.170.223.2554,094
17529.170.224.0/2029.170.224.1 to 29.170.239.25429.170.239.2554,094
17629.170.240.0/2029.170.240.1 to 29.170.255.25429.170.255.2554,094
17729.171.0.0/2029.171.0.1 to 29.171.15.25429.171.15.2554,094
17829.171.16.0/2029.171.16.1 to 29.171.31.25429.171.31.2554,094
17929.171.32.0/2029.171.32.1 to 29.171.47.25429.171.47.2554,094
18029.171.48.0/2029.171.48.1 to 29.171.63.25429.171.63.2554,094
18129.171.64.0/2029.171.64.1 to 29.171.79.25429.171.79.2554,094
18229.171.80.0/2029.171.80.1 to 29.171.95.25429.171.95.2554,094
18329.171.96.0/2029.171.96.1 to 29.171.111.25429.171.111.2554,094
18429.171.112.0/2029.171.112.1 to 29.171.127.25429.171.127.2554,094
18529.171.128.0/2029.171.128.1 to 29.171.143.25429.171.143.2554,094
18629.171.144.0/2029.171.144.1 to 29.171.159.25429.171.159.2554,094
18729.171.160.0/2029.171.160.1 to 29.171.175.25429.171.175.2554,094
18829.171.176.0/2029.171.176.1 to 29.171.191.25429.171.191.2554,094
18929.171.192.0/2029.171.192.1 to 29.171.207.25429.171.207.2554,094
19029.171.208.0/2029.171.208.1 to 29.171.223.25429.171.223.2554,094
19129.171.224.0/2029.171.224.1 to 29.171.239.25429.171.239.2554,094
19229.171.240.0/2029.171.240.1 to 29.171.255.25429.171.255.2554,094
19329.172.0.0/2029.172.0.1 to 29.172.15.25429.172.15.2554,094
19429.172.16.0/2029.172.16.1 to 29.172.31.25429.172.31.2554,094
19529.172.32.0/2029.172.32.1 to 29.172.47.25429.172.47.2554,094
19629.172.48.0/2029.172.48.1 to 29.172.63.25429.172.63.2554,094
19729.172.64.0/2029.172.64.1 to 29.172.79.25429.172.79.2554,094
19829.172.80.0/2029.172.80.1 to 29.172.95.25429.172.95.2554,094
19929.172.96.0/2029.172.96.1 to 29.172.111.25429.172.111.2554,094
20029.172.112.0/2029.172.112.1 to 29.172.127.25429.172.127.2554,094
20129.172.128.0/2029.172.128.1 to 29.172.143.25429.172.143.2554,094
20229.172.144.0/2029.172.144.1 to 29.172.159.25429.172.159.2554,094
20329.172.160.0/2029.172.160.1 to 29.172.175.25429.172.175.2554,094
20429.172.176.0/2029.172.176.1 to 29.172.191.25429.172.191.2554,094
20529.172.192.0/2029.172.192.1 to 29.172.207.25429.172.207.2554,094
20629.172.208.0/2029.172.208.1 to 29.172.223.25429.172.223.2554,094
20729.172.224.0/2029.172.224.1 to 29.172.239.25429.172.239.2554,094
20829.172.240.0/2029.172.240.1 to 29.172.255.25429.172.255.2554,094
20929.173.0.0/2029.173.0.1 to 29.173.15.25429.173.15.2554,094
21029.173.16.0/2029.173.16.1 to 29.173.31.25429.173.31.2554,094
21129.173.32.0/2029.173.32.1 to 29.173.47.25429.173.47.2554,094
21229.173.48.0/2029.173.48.1 to 29.173.63.25429.173.63.2554,094
21329.173.64.0/2029.173.64.1 to 29.173.79.25429.173.79.2554,094
21429.173.80.0/2029.173.80.1 to 29.173.95.25429.173.95.2554,094
21529.173.96.0/2029.173.96.1 to 29.173.111.25429.173.111.2554,094
21629.173.112.0/2029.173.112.1 to 29.173.127.25429.173.127.2554,094
21729.173.128.0/2029.173.128.1 to 29.173.143.25429.173.143.2554,094
21829.173.144.0/2029.173.144.1 to 29.173.159.25429.173.159.2554,094
21929.173.160.0/2029.173.160.1 to 29.173.175.25429.173.175.2554,094
22029.173.176.0/2029.173.176.1 to 29.173.191.25429.173.191.2554,094
22129.173.192.0/2029.173.192.1 to 29.173.207.25429.173.207.2554,094
22229.173.208.0/2029.173.208.1 to 29.173.223.25429.173.223.2554,094
22329.173.224.0/2029.173.224.1 to 29.173.239.25429.173.239.2554,094
22429.173.240.0/2029.173.240.1 to 29.173.255.25429.173.255.2554,094
22529.174.0.0/2029.174.0.1 to 29.174.15.25429.174.15.2554,094
22629.174.16.0/2029.174.16.1 to 29.174.31.25429.174.31.2554,094
22729.174.32.0/2029.174.32.1 to 29.174.47.25429.174.47.2554,094
22829.174.48.0/2029.174.48.1 to 29.174.63.25429.174.63.2554,094
22929.174.64.0/2029.174.64.1 to 29.174.79.25429.174.79.2554,094
23029.174.80.0/2029.174.80.1 to 29.174.95.25429.174.95.2554,094
23129.174.96.0/2029.174.96.1 to 29.174.111.25429.174.111.2554,094
23229.174.112.0/2029.174.112.1 to 29.174.127.25429.174.127.2554,094
23329.174.128.0/2029.174.128.1 to 29.174.143.25429.174.143.2554,094
23429.174.144.0/2029.174.144.1 to 29.174.159.25429.174.159.2554,094
23529.174.160.0/2029.174.160.1 to 29.174.175.25429.174.175.2554,094
23629.174.176.0/2029.174.176.1 to 29.174.191.25429.174.191.2554,094
23729.174.192.0/2029.174.192.1 to 29.174.207.25429.174.207.2554,094
23829.174.208.0/2029.174.208.1 to 29.174.223.25429.174.223.2554,094
23929.174.224.0/2029.174.224.1 to 29.174.239.25429.174.239.2554,094
24029.174.240.0/2029.174.240.1 to 29.174.255.25429.174.255.2554,094
24129.175.0.0/2029.175.0.1 to 29.175.15.25429.175.15.2554,094
24229.175.16.0/2029.175.16.1 to 29.175.31.25429.175.31.2554,094
24329.175.32.0/2029.175.32.1 to 29.175.47.25429.175.47.2554,094
24429.175.48.0/2029.175.48.1 to 29.175.63.25429.175.63.2554,094
24529.175.64.0/2029.175.64.1 to 29.175.79.25429.175.79.2554,094
24629.175.80.0/2029.175.80.1 to 29.175.95.25429.175.95.2554,094
24729.175.96.0/2029.175.96.1 to 29.175.111.25429.175.111.2554,094
24829.175.112.0/2029.175.112.1 to 29.175.127.25429.175.127.2554,094
24929.175.128.0/2029.175.128.1 to 29.175.143.25429.175.143.2554,094
25029.175.144.0/2029.175.144.1 to 29.175.159.25429.175.159.2554,094
25129.175.160.0/2029.175.160.1 to 29.175.175.25429.175.175.2554,094
25229.175.176.0/2029.175.176.1 to 29.175.191.25429.175.191.2554,094
25329.175.192.0/2029.175.192.1 to 29.175.207.25429.175.207.2554,094
25429.175.208.0/2029.175.208.1 to 29.175.223.25429.175.223.2554,094
25529.175.224.0/2029.175.224.1 to 29.175.239.25429.175.239.2554,094
25629.175.240.0/2029.175.240.1 to 29.175.255.25429.175.255.2554,094

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.