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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.

Network48.128.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
48.128.0.0
Broadcast address
48.191.255.255
First usable
48.128.0.1
Last usable
48.191.255.254
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 30800000 · Integer 813694976 to 817889279
Reverse DNS zones
128.48.in-addr.arpa
129.48.in-addr.arpa
130.48.in-addr.arpa
131.48.in-addr.arpa
132.48.in-addr.arpa
133.48.in-addr.arpa
134.48.in-addr.arpa
135.48.in-addr.arpa
136.48.in-addr.arpa
137.48.in-addr.arpa
138.48.in-addr.arpa
139.48.in-addr.arpa
140.48.in-addr.arpa
141.48.in-addr.arpa
142.48.in-addr.arpa
143.48.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
Address00110000.10000000.00000000.0000000048.128.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110000.10000000.00000000.0000000048.128.0.0
Broadcast00110000.10111111.11111111.1111111148.191.255.255
Split into smaller subnets/18
/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)

48.128.0.0/10 makes 256 subnets of /18.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
148.128.0.0/1848.128.0.1 to 48.128.63.25448.128.63.25516,382
248.128.64.0/1848.128.64.1 to 48.128.127.25448.128.127.25516,382
348.128.128.0/1848.128.128.1 to 48.128.191.25448.128.191.25516,382
448.128.192.0/1848.128.192.1 to 48.128.255.25448.128.255.25516,382
548.129.0.0/1848.129.0.1 to 48.129.63.25448.129.63.25516,382
648.129.64.0/1848.129.64.1 to 48.129.127.25448.129.127.25516,382
748.129.128.0/1848.129.128.1 to 48.129.191.25448.129.191.25516,382
848.129.192.0/1848.129.192.1 to 48.129.255.25448.129.255.25516,382
948.130.0.0/1848.130.0.1 to 48.130.63.25448.130.63.25516,382
1048.130.64.0/1848.130.64.1 to 48.130.127.25448.130.127.25516,382
1148.130.128.0/1848.130.128.1 to 48.130.191.25448.130.191.25516,382
1248.130.192.0/1848.130.192.1 to 48.130.255.25448.130.255.25516,382
1348.131.0.0/1848.131.0.1 to 48.131.63.25448.131.63.25516,382
1448.131.64.0/1848.131.64.1 to 48.131.127.25448.131.127.25516,382
1548.131.128.0/1848.131.128.1 to 48.131.191.25448.131.191.25516,382
1648.131.192.0/1848.131.192.1 to 48.131.255.25448.131.255.25516,382
1748.132.0.0/1848.132.0.1 to 48.132.63.25448.132.63.25516,382
1848.132.64.0/1848.132.64.1 to 48.132.127.25448.132.127.25516,382
1948.132.128.0/1848.132.128.1 to 48.132.191.25448.132.191.25516,382
2048.132.192.0/1848.132.192.1 to 48.132.255.25448.132.255.25516,382
2148.133.0.0/1848.133.0.1 to 48.133.63.25448.133.63.25516,382
2248.133.64.0/1848.133.64.1 to 48.133.127.25448.133.127.25516,382
2348.133.128.0/1848.133.128.1 to 48.133.191.25448.133.191.25516,382
2448.133.192.0/1848.133.192.1 to 48.133.255.25448.133.255.25516,382
2548.134.0.0/1848.134.0.1 to 48.134.63.25448.134.63.25516,382
2648.134.64.0/1848.134.64.1 to 48.134.127.25448.134.127.25516,382
2748.134.128.0/1848.134.128.1 to 48.134.191.25448.134.191.25516,382
2848.134.192.0/1848.134.192.1 to 48.134.255.25448.134.255.25516,382
2948.135.0.0/1848.135.0.1 to 48.135.63.25448.135.63.25516,382
3048.135.64.0/1848.135.64.1 to 48.135.127.25448.135.127.25516,382
3148.135.128.0/1848.135.128.1 to 48.135.191.25448.135.191.25516,382
3248.135.192.0/1848.135.192.1 to 48.135.255.25448.135.255.25516,382
3348.136.0.0/1848.136.0.1 to 48.136.63.25448.136.63.25516,382
3448.136.64.0/1848.136.64.1 to 48.136.127.25448.136.127.25516,382
3548.136.128.0/1848.136.128.1 to 48.136.191.25448.136.191.25516,382
3648.136.192.0/1848.136.192.1 to 48.136.255.25448.136.255.25516,382
3748.137.0.0/1848.137.0.1 to 48.137.63.25448.137.63.25516,382
3848.137.64.0/1848.137.64.1 to 48.137.127.25448.137.127.25516,382
3948.137.128.0/1848.137.128.1 to 48.137.191.25448.137.191.25516,382
4048.137.192.0/1848.137.192.1 to 48.137.255.25448.137.255.25516,382
4148.138.0.0/1848.138.0.1 to 48.138.63.25448.138.63.25516,382
4248.138.64.0/1848.138.64.1 to 48.138.127.25448.138.127.25516,382
4348.138.128.0/1848.138.128.1 to 48.138.191.25448.138.191.25516,382
4448.138.192.0/1848.138.192.1 to 48.138.255.25448.138.255.25516,382
4548.139.0.0/1848.139.0.1 to 48.139.63.25448.139.63.25516,382
4648.139.64.0/1848.139.64.1 to 48.139.127.25448.139.127.25516,382
4748.139.128.0/1848.139.128.1 to 48.139.191.25448.139.191.25516,382
4848.139.192.0/1848.139.192.1 to 48.139.255.25448.139.255.25516,382
4948.140.0.0/1848.140.0.1 to 48.140.63.25448.140.63.25516,382
5048.140.64.0/1848.140.64.1 to 48.140.127.25448.140.127.25516,382
5148.140.128.0/1848.140.128.1 to 48.140.191.25448.140.191.25516,382
5248.140.192.0/1848.140.192.1 to 48.140.255.25448.140.255.25516,382
5348.141.0.0/1848.141.0.1 to 48.141.63.25448.141.63.25516,382
5448.141.64.0/1848.141.64.1 to 48.141.127.25448.141.127.25516,382
5548.141.128.0/1848.141.128.1 to 48.141.191.25448.141.191.25516,382
5648.141.192.0/1848.141.192.1 to 48.141.255.25448.141.255.25516,382
5748.142.0.0/1848.142.0.1 to 48.142.63.25448.142.63.25516,382
5848.142.64.0/1848.142.64.1 to 48.142.127.25448.142.127.25516,382
5948.142.128.0/1848.142.128.1 to 48.142.191.25448.142.191.25516,382
6048.142.192.0/1848.142.192.1 to 48.142.255.25448.142.255.25516,382
6148.143.0.0/1848.143.0.1 to 48.143.63.25448.143.63.25516,382
6248.143.64.0/1848.143.64.1 to 48.143.127.25448.143.127.25516,382
6348.143.128.0/1848.143.128.1 to 48.143.191.25448.143.191.25516,382
6448.143.192.0/1848.143.192.1 to 48.143.255.25448.143.255.25516,382
6548.144.0.0/1848.144.0.1 to 48.144.63.25448.144.63.25516,382
6648.144.64.0/1848.144.64.1 to 48.144.127.25448.144.127.25516,382
6748.144.128.0/1848.144.128.1 to 48.144.191.25448.144.191.25516,382
6848.144.192.0/1848.144.192.1 to 48.144.255.25448.144.255.25516,382
6948.145.0.0/1848.145.0.1 to 48.145.63.25448.145.63.25516,382
7048.145.64.0/1848.145.64.1 to 48.145.127.25448.145.127.25516,382
7148.145.128.0/1848.145.128.1 to 48.145.191.25448.145.191.25516,382
7248.145.192.0/1848.145.192.1 to 48.145.255.25448.145.255.25516,382
7348.146.0.0/1848.146.0.1 to 48.146.63.25448.146.63.25516,382
7448.146.64.0/1848.146.64.1 to 48.146.127.25448.146.127.25516,382
7548.146.128.0/1848.146.128.1 to 48.146.191.25448.146.191.25516,382
7648.146.192.0/1848.146.192.1 to 48.146.255.25448.146.255.25516,382
7748.147.0.0/1848.147.0.1 to 48.147.63.25448.147.63.25516,382
7848.147.64.0/1848.147.64.1 to 48.147.127.25448.147.127.25516,382
7948.147.128.0/1848.147.128.1 to 48.147.191.25448.147.191.25516,382
8048.147.192.0/1848.147.192.1 to 48.147.255.25448.147.255.25516,382
8148.148.0.0/1848.148.0.1 to 48.148.63.25448.148.63.25516,382
8248.148.64.0/1848.148.64.1 to 48.148.127.25448.148.127.25516,382
8348.148.128.0/1848.148.128.1 to 48.148.191.25448.148.191.25516,382
8448.148.192.0/1848.148.192.1 to 48.148.255.25448.148.255.25516,382
8548.149.0.0/1848.149.0.1 to 48.149.63.25448.149.63.25516,382
8648.149.64.0/1848.149.64.1 to 48.149.127.25448.149.127.25516,382
8748.149.128.0/1848.149.128.1 to 48.149.191.25448.149.191.25516,382
8848.149.192.0/1848.149.192.1 to 48.149.255.25448.149.255.25516,382
8948.150.0.0/1848.150.0.1 to 48.150.63.25448.150.63.25516,382
9048.150.64.0/1848.150.64.1 to 48.150.127.25448.150.127.25516,382
9148.150.128.0/1848.150.128.1 to 48.150.191.25448.150.191.25516,382
9248.150.192.0/1848.150.192.1 to 48.150.255.25448.150.255.25516,382
9348.151.0.0/1848.151.0.1 to 48.151.63.25448.151.63.25516,382
9448.151.64.0/1848.151.64.1 to 48.151.127.25448.151.127.25516,382
9548.151.128.0/1848.151.128.1 to 48.151.191.25448.151.191.25516,382
9648.151.192.0/1848.151.192.1 to 48.151.255.25448.151.255.25516,382
9748.152.0.0/1848.152.0.1 to 48.152.63.25448.152.63.25516,382
9848.152.64.0/1848.152.64.1 to 48.152.127.25448.152.127.25516,382
9948.152.128.0/1848.152.128.1 to 48.152.191.25448.152.191.25516,382
10048.152.192.0/1848.152.192.1 to 48.152.255.25448.152.255.25516,382
10148.153.0.0/1848.153.0.1 to 48.153.63.25448.153.63.25516,382
10248.153.64.0/1848.153.64.1 to 48.153.127.25448.153.127.25516,382
10348.153.128.0/1848.153.128.1 to 48.153.191.25448.153.191.25516,382
10448.153.192.0/1848.153.192.1 to 48.153.255.25448.153.255.25516,382
10548.154.0.0/1848.154.0.1 to 48.154.63.25448.154.63.25516,382
10648.154.64.0/1848.154.64.1 to 48.154.127.25448.154.127.25516,382
10748.154.128.0/1848.154.128.1 to 48.154.191.25448.154.191.25516,382
10848.154.192.0/1848.154.192.1 to 48.154.255.25448.154.255.25516,382
10948.155.0.0/1848.155.0.1 to 48.155.63.25448.155.63.25516,382
11048.155.64.0/1848.155.64.1 to 48.155.127.25448.155.127.25516,382
11148.155.128.0/1848.155.128.1 to 48.155.191.25448.155.191.25516,382
11248.155.192.0/1848.155.192.1 to 48.155.255.25448.155.255.25516,382
11348.156.0.0/1848.156.0.1 to 48.156.63.25448.156.63.25516,382
11448.156.64.0/1848.156.64.1 to 48.156.127.25448.156.127.25516,382
11548.156.128.0/1848.156.128.1 to 48.156.191.25448.156.191.25516,382
11648.156.192.0/1848.156.192.1 to 48.156.255.25448.156.255.25516,382
11748.157.0.0/1848.157.0.1 to 48.157.63.25448.157.63.25516,382
11848.157.64.0/1848.157.64.1 to 48.157.127.25448.157.127.25516,382
11948.157.128.0/1848.157.128.1 to 48.157.191.25448.157.191.25516,382
12048.157.192.0/1848.157.192.1 to 48.157.255.25448.157.255.25516,382
12148.158.0.0/1848.158.0.1 to 48.158.63.25448.158.63.25516,382
12248.158.64.0/1848.158.64.1 to 48.158.127.25448.158.127.25516,382
12348.158.128.0/1848.158.128.1 to 48.158.191.25448.158.191.25516,382
12448.158.192.0/1848.158.192.1 to 48.158.255.25448.158.255.25516,382
12548.159.0.0/1848.159.0.1 to 48.159.63.25448.159.63.25516,382
12648.159.64.0/1848.159.64.1 to 48.159.127.25448.159.127.25516,382
12748.159.128.0/1848.159.128.1 to 48.159.191.25448.159.191.25516,382
12848.159.192.0/1848.159.192.1 to 48.159.255.25448.159.255.25516,382
12948.160.0.0/1848.160.0.1 to 48.160.63.25448.160.63.25516,382
13048.160.64.0/1848.160.64.1 to 48.160.127.25448.160.127.25516,382
13148.160.128.0/1848.160.128.1 to 48.160.191.25448.160.191.25516,382
13248.160.192.0/1848.160.192.1 to 48.160.255.25448.160.255.25516,382
13348.161.0.0/1848.161.0.1 to 48.161.63.25448.161.63.25516,382
13448.161.64.0/1848.161.64.1 to 48.161.127.25448.161.127.25516,382
13548.161.128.0/1848.161.128.1 to 48.161.191.25448.161.191.25516,382
13648.161.192.0/1848.161.192.1 to 48.161.255.25448.161.255.25516,382
13748.162.0.0/1848.162.0.1 to 48.162.63.25448.162.63.25516,382
13848.162.64.0/1848.162.64.1 to 48.162.127.25448.162.127.25516,382
13948.162.128.0/1848.162.128.1 to 48.162.191.25448.162.191.25516,382
14048.162.192.0/1848.162.192.1 to 48.162.255.25448.162.255.25516,382
14148.163.0.0/1848.163.0.1 to 48.163.63.25448.163.63.25516,382
14248.163.64.0/1848.163.64.1 to 48.163.127.25448.163.127.25516,382
14348.163.128.0/1848.163.128.1 to 48.163.191.25448.163.191.25516,382
14448.163.192.0/1848.163.192.1 to 48.163.255.25448.163.255.25516,382
14548.164.0.0/1848.164.0.1 to 48.164.63.25448.164.63.25516,382
14648.164.64.0/1848.164.64.1 to 48.164.127.25448.164.127.25516,382
14748.164.128.0/1848.164.128.1 to 48.164.191.25448.164.191.25516,382
14848.164.192.0/1848.164.192.1 to 48.164.255.25448.164.255.25516,382
14948.165.0.0/1848.165.0.1 to 48.165.63.25448.165.63.25516,382
15048.165.64.0/1848.165.64.1 to 48.165.127.25448.165.127.25516,382
15148.165.128.0/1848.165.128.1 to 48.165.191.25448.165.191.25516,382
15248.165.192.0/1848.165.192.1 to 48.165.255.25448.165.255.25516,382
15348.166.0.0/1848.166.0.1 to 48.166.63.25448.166.63.25516,382
15448.166.64.0/1848.166.64.1 to 48.166.127.25448.166.127.25516,382
15548.166.128.0/1848.166.128.1 to 48.166.191.25448.166.191.25516,382
15648.166.192.0/1848.166.192.1 to 48.166.255.25448.166.255.25516,382
15748.167.0.0/1848.167.0.1 to 48.167.63.25448.167.63.25516,382
15848.167.64.0/1848.167.64.1 to 48.167.127.25448.167.127.25516,382
15948.167.128.0/1848.167.128.1 to 48.167.191.25448.167.191.25516,382
16048.167.192.0/1848.167.192.1 to 48.167.255.25448.167.255.25516,382
16148.168.0.0/1848.168.0.1 to 48.168.63.25448.168.63.25516,382
16248.168.64.0/1848.168.64.1 to 48.168.127.25448.168.127.25516,382
16348.168.128.0/1848.168.128.1 to 48.168.191.25448.168.191.25516,382
16448.168.192.0/1848.168.192.1 to 48.168.255.25448.168.255.25516,382
16548.169.0.0/1848.169.0.1 to 48.169.63.25448.169.63.25516,382
16648.169.64.0/1848.169.64.1 to 48.169.127.25448.169.127.25516,382
16748.169.128.0/1848.169.128.1 to 48.169.191.25448.169.191.25516,382
16848.169.192.0/1848.169.192.1 to 48.169.255.25448.169.255.25516,382
16948.170.0.0/1848.170.0.1 to 48.170.63.25448.170.63.25516,382
17048.170.64.0/1848.170.64.1 to 48.170.127.25448.170.127.25516,382
17148.170.128.0/1848.170.128.1 to 48.170.191.25448.170.191.25516,382
17248.170.192.0/1848.170.192.1 to 48.170.255.25448.170.255.25516,382
17348.171.0.0/1848.171.0.1 to 48.171.63.25448.171.63.25516,382
17448.171.64.0/1848.171.64.1 to 48.171.127.25448.171.127.25516,382
17548.171.128.0/1848.171.128.1 to 48.171.191.25448.171.191.25516,382
17648.171.192.0/1848.171.192.1 to 48.171.255.25448.171.255.25516,382
17748.172.0.0/1848.172.0.1 to 48.172.63.25448.172.63.25516,382
17848.172.64.0/1848.172.64.1 to 48.172.127.25448.172.127.25516,382
17948.172.128.0/1848.172.128.1 to 48.172.191.25448.172.191.25516,382
18048.172.192.0/1848.172.192.1 to 48.172.255.25448.172.255.25516,382
18148.173.0.0/1848.173.0.1 to 48.173.63.25448.173.63.25516,382
18248.173.64.0/1848.173.64.1 to 48.173.127.25448.173.127.25516,382
18348.173.128.0/1848.173.128.1 to 48.173.191.25448.173.191.25516,382
18448.173.192.0/1848.173.192.1 to 48.173.255.25448.173.255.25516,382
18548.174.0.0/1848.174.0.1 to 48.174.63.25448.174.63.25516,382
18648.174.64.0/1848.174.64.1 to 48.174.127.25448.174.127.25516,382
18748.174.128.0/1848.174.128.1 to 48.174.191.25448.174.191.25516,382
18848.174.192.0/1848.174.192.1 to 48.174.255.25448.174.255.25516,382
18948.175.0.0/1848.175.0.1 to 48.175.63.25448.175.63.25516,382
19048.175.64.0/1848.175.64.1 to 48.175.127.25448.175.127.25516,382
19148.175.128.0/1848.175.128.1 to 48.175.191.25448.175.191.25516,382
19248.175.192.0/1848.175.192.1 to 48.175.255.25448.175.255.25516,382
19348.176.0.0/1848.176.0.1 to 48.176.63.25448.176.63.25516,382
19448.176.64.0/1848.176.64.1 to 48.176.127.25448.176.127.25516,382
19548.176.128.0/1848.176.128.1 to 48.176.191.25448.176.191.25516,382
19648.176.192.0/1848.176.192.1 to 48.176.255.25448.176.255.25516,382
19748.177.0.0/1848.177.0.1 to 48.177.63.25448.177.63.25516,382
19848.177.64.0/1848.177.64.1 to 48.177.127.25448.177.127.25516,382
19948.177.128.0/1848.177.128.1 to 48.177.191.25448.177.191.25516,382
20048.177.192.0/1848.177.192.1 to 48.177.255.25448.177.255.25516,382
20148.178.0.0/1848.178.0.1 to 48.178.63.25448.178.63.25516,382
20248.178.64.0/1848.178.64.1 to 48.178.127.25448.178.127.25516,382
20348.178.128.0/1848.178.128.1 to 48.178.191.25448.178.191.25516,382
20448.178.192.0/1848.178.192.1 to 48.178.255.25448.178.255.25516,382
20548.179.0.0/1848.179.0.1 to 48.179.63.25448.179.63.25516,382
20648.179.64.0/1848.179.64.1 to 48.179.127.25448.179.127.25516,382
20748.179.128.0/1848.179.128.1 to 48.179.191.25448.179.191.25516,382
20848.179.192.0/1848.179.192.1 to 48.179.255.25448.179.255.25516,382
20948.180.0.0/1848.180.0.1 to 48.180.63.25448.180.63.25516,382
21048.180.64.0/1848.180.64.1 to 48.180.127.25448.180.127.25516,382
21148.180.128.0/1848.180.128.1 to 48.180.191.25448.180.191.25516,382
21248.180.192.0/1848.180.192.1 to 48.180.255.25448.180.255.25516,382
21348.181.0.0/1848.181.0.1 to 48.181.63.25448.181.63.25516,382
21448.181.64.0/1848.181.64.1 to 48.181.127.25448.181.127.25516,382
21548.181.128.0/1848.181.128.1 to 48.181.191.25448.181.191.25516,382
21648.181.192.0/1848.181.192.1 to 48.181.255.25448.181.255.25516,382
21748.182.0.0/1848.182.0.1 to 48.182.63.25448.182.63.25516,382
21848.182.64.0/1848.182.64.1 to 48.182.127.25448.182.127.25516,382
21948.182.128.0/1848.182.128.1 to 48.182.191.25448.182.191.25516,382
22048.182.192.0/1848.182.192.1 to 48.182.255.25448.182.255.25516,382
22148.183.0.0/1848.183.0.1 to 48.183.63.25448.183.63.25516,382
22248.183.64.0/1848.183.64.1 to 48.183.127.25448.183.127.25516,382
22348.183.128.0/1848.183.128.1 to 48.183.191.25448.183.191.25516,382
22448.183.192.0/1848.183.192.1 to 48.183.255.25448.183.255.25516,382
22548.184.0.0/1848.184.0.1 to 48.184.63.25448.184.63.25516,382
22648.184.64.0/1848.184.64.1 to 48.184.127.25448.184.127.25516,382
22748.184.128.0/1848.184.128.1 to 48.184.191.25448.184.191.25516,382
22848.184.192.0/1848.184.192.1 to 48.184.255.25448.184.255.25516,382
22948.185.0.0/1848.185.0.1 to 48.185.63.25448.185.63.25516,382
23048.185.64.0/1848.185.64.1 to 48.185.127.25448.185.127.25516,382
23148.185.128.0/1848.185.128.1 to 48.185.191.25448.185.191.25516,382
23248.185.192.0/1848.185.192.1 to 48.185.255.25448.185.255.25516,382
23348.186.0.0/1848.186.0.1 to 48.186.63.25448.186.63.25516,382
23448.186.64.0/1848.186.64.1 to 48.186.127.25448.186.127.25516,382
23548.186.128.0/1848.186.128.1 to 48.186.191.25448.186.191.25516,382
23648.186.192.0/1848.186.192.1 to 48.186.255.25448.186.255.25516,382
23748.187.0.0/1848.187.0.1 to 48.187.63.25448.187.63.25516,382
23848.187.64.0/1848.187.64.1 to 48.187.127.25448.187.127.25516,382
23948.187.128.0/1848.187.128.1 to 48.187.191.25448.187.191.25516,382
24048.187.192.0/1848.187.192.1 to 48.187.255.25448.187.255.25516,382
24148.188.0.0/1848.188.0.1 to 48.188.63.25448.188.63.25516,382
24248.188.64.0/1848.188.64.1 to 48.188.127.25448.188.127.25516,382
24348.188.128.0/1848.188.128.1 to 48.188.191.25448.188.191.25516,382
24448.188.192.0/1848.188.192.1 to 48.188.255.25448.188.255.25516,382
24548.189.0.0/1848.189.0.1 to 48.189.63.25448.189.63.25516,382
24648.189.64.0/1848.189.64.1 to 48.189.127.25448.189.127.25516,382
24748.189.128.0/1848.189.128.1 to 48.189.191.25448.189.191.25516,382
24848.189.192.0/1848.189.192.1 to 48.189.255.25448.189.255.25516,382
24948.190.0.0/1848.190.0.1 to 48.190.63.25448.190.63.25516,382
25048.190.64.0/1848.190.64.1 to 48.190.127.25448.190.127.25516,382
25148.190.128.0/1848.190.128.1 to 48.190.191.25448.190.191.25516,382
25248.190.192.0/1848.190.192.1 to 48.190.255.25448.190.255.25516,382
25348.191.0.0/1848.191.0.1 to 48.191.63.25448.191.63.25516,382
25448.191.64.0/1848.191.64.1 to 48.191.127.25448.191.127.25516,382
25548.191.128.0/1848.191.128.1 to 48.191.191.25448.191.191.25516,382
25648.191.192.0/1848.191.192.1 to 48.191.255.25448.191.255.25516,382

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.