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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.

Network95.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
95.0.0.0
Broadcast address
95.255.255.255
First usable
95.0.0.1
Last usable
95.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 5F000000 · Integer 1593835520 to 1610612735
Reverse DNS zone
95.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011111..00000000.00000000.0000000095.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01011111..00000000.00000000.0000000095.0.0.0
Broadcast01011111..11111111.11111111.1111111195.255.255.255
Split into smaller subnets/20
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

95.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
195.0.0.0/2095.0.0.1 to 95.0.15.25495.0.15.2554,094
295.0.16.0/2095.0.16.1 to 95.0.31.25495.0.31.2554,094
395.0.32.0/2095.0.32.1 to 95.0.47.25495.0.47.2554,094
495.0.48.0/2095.0.48.1 to 95.0.63.25495.0.63.2554,094
595.0.64.0/2095.0.64.1 to 95.0.79.25495.0.79.2554,094
695.0.80.0/2095.0.80.1 to 95.0.95.25495.0.95.2554,094
795.0.96.0/2095.0.96.1 to 95.0.111.25495.0.111.2554,094
895.0.112.0/2095.0.112.1 to 95.0.127.25495.0.127.2554,094
995.0.128.0/2095.0.128.1 to 95.0.143.25495.0.143.2554,094
1095.0.144.0/2095.0.144.1 to 95.0.159.25495.0.159.2554,094
1195.0.160.0/2095.0.160.1 to 95.0.175.25495.0.175.2554,094
1295.0.176.0/2095.0.176.1 to 95.0.191.25495.0.191.2554,094
1395.0.192.0/2095.0.192.1 to 95.0.207.25495.0.207.2554,094
1495.0.208.0/2095.0.208.1 to 95.0.223.25495.0.223.2554,094
1595.0.224.0/2095.0.224.1 to 95.0.239.25495.0.239.2554,094
1695.0.240.0/2095.0.240.1 to 95.0.255.25495.0.255.2554,094
1795.1.0.0/2095.1.0.1 to 95.1.15.25495.1.15.2554,094
1895.1.16.0/2095.1.16.1 to 95.1.31.25495.1.31.2554,094
1995.1.32.0/2095.1.32.1 to 95.1.47.25495.1.47.2554,094
2095.1.48.0/2095.1.48.1 to 95.1.63.25495.1.63.2554,094
2195.1.64.0/2095.1.64.1 to 95.1.79.25495.1.79.2554,094
2295.1.80.0/2095.1.80.1 to 95.1.95.25495.1.95.2554,094
2395.1.96.0/2095.1.96.1 to 95.1.111.25495.1.111.2554,094
2495.1.112.0/2095.1.112.1 to 95.1.127.25495.1.127.2554,094
2595.1.128.0/2095.1.128.1 to 95.1.143.25495.1.143.2554,094
2695.1.144.0/2095.1.144.1 to 95.1.159.25495.1.159.2554,094
2795.1.160.0/2095.1.160.1 to 95.1.175.25495.1.175.2554,094
2895.1.176.0/2095.1.176.1 to 95.1.191.25495.1.191.2554,094
2995.1.192.0/2095.1.192.1 to 95.1.207.25495.1.207.2554,094
3095.1.208.0/2095.1.208.1 to 95.1.223.25495.1.223.2554,094
3195.1.224.0/2095.1.224.1 to 95.1.239.25495.1.239.2554,094
3295.1.240.0/2095.1.240.1 to 95.1.255.25495.1.255.2554,094
3395.2.0.0/2095.2.0.1 to 95.2.15.25495.2.15.2554,094
3495.2.16.0/2095.2.16.1 to 95.2.31.25495.2.31.2554,094
3595.2.32.0/2095.2.32.1 to 95.2.47.25495.2.47.2554,094
3695.2.48.0/2095.2.48.1 to 95.2.63.25495.2.63.2554,094
3795.2.64.0/2095.2.64.1 to 95.2.79.25495.2.79.2554,094
3895.2.80.0/2095.2.80.1 to 95.2.95.25495.2.95.2554,094
3995.2.96.0/2095.2.96.1 to 95.2.111.25495.2.111.2554,094
4095.2.112.0/2095.2.112.1 to 95.2.127.25495.2.127.2554,094
4195.2.128.0/2095.2.128.1 to 95.2.143.25495.2.143.2554,094
4295.2.144.0/2095.2.144.1 to 95.2.159.25495.2.159.2554,094
4395.2.160.0/2095.2.160.1 to 95.2.175.25495.2.175.2554,094
4495.2.176.0/2095.2.176.1 to 95.2.191.25495.2.191.2554,094
4595.2.192.0/2095.2.192.1 to 95.2.207.25495.2.207.2554,094
4695.2.208.0/2095.2.208.1 to 95.2.223.25495.2.223.2554,094
4795.2.224.0/2095.2.224.1 to 95.2.239.25495.2.239.2554,094
4895.2.240.0/2095.2.240.1 to 95.2.255.25495.2.255.2554,094
4995.3.0.0/2095.3.0.1 to 95.3.15.25495.3.15.2554,094
5095.3.16.0/2095.3.16.1 to 95.3.31.25495.3.31.2554,094
5195.3.32.0/2095.3.32.1 to 95.3.47.25495.3.47.2554,094
5295.3.48.0/2095.3.48.1 to 95.3.63.25495.3.63.2554,094
5395.3.64.0/2095.3.64.1 to 95.3.79.25495.3.79.2554,094
5495.3.80.0/2095.3.80.1 to 95.3.95.25495.3.95.2554,094
5595.3.96.0/2095.3.96.1 to 95.3.111.25495.3.111.2554,094
5695.3.112.0/2095.3.112.1 to 95.3.127.25495.3.127.2554,094
5795.3.128.0/2095.3.128.1 to 95.3.143.25495.3.143.2554,094
5895.3.144.0/2095.3.144.1 to 95.3.159.25495.3.159.2554,094
5995.3.160.0/2095.3.160.1 to 95.3.175.25495.3.175.2554,094
6095.3.176.0/2095.3.176.1 to 95.3.191.25495.3.191.2554,094
6195.3.192.0/2095.3.192.1 to 95.3.207.25495.3.207.2554,094
6295.3.208.0/2095.3.208.1 to 95.3.223.25495.3.223.2554,094
6395.3.224.0/2095.3.224.1 to 95.3.239.25495.3.239.2554,094
6495.3.240.0/2095.3.240.1 to 95.3.255.25495.3.255.2554,094
6595.4.0.0/2095.4.0.1 to 95.4.15.25495.4.15.2554,094
6695.4.16.0/2095.4.16.1 to 95.4.31.25495.4.31.2554,094
6795.4.32.0/2095.4.32.1 to 95.4.47.25495.4.47.2554,094
6895.4.48.0/2095.4.48.1 to 95.4.63.25495.4.63.2554,094
6995.4.64.0/2095.4.64.1 to 95.4.79.25495.4.79.2554,094
7095.4.80.0/2095.4.80.1 to 95.4.95.25495.4.95.2554,094
7195.4.96.0/2095.4.96.1 to 95.4.111.25495.4.111.2554,094
7295.4.112.0/2095.4.112.1 to 95.4.127.25495.4.127.2554,094
7395.4.128.0/2095.4.128.1 to 95.4.143.25495.4.143.2554,094
7495.4.144.0/2095.4.144.1 to 95.4.159.25495.4.159.2554,094
7595.4.160.0/2095.4.160.1 to 95.4.175.25495.4.175.2554,094
7695.4.176.0/2095.4.176.1 to 95.4.191.25495.4.191.2554,094
7795.4.192.0/2095.4.192.1 to 95.4.207.25495.4.207.2554,094
7895.4.208.0/2095.4.208.1 to 95.4.223.25495.4.223.2554,094
7995.4.224.0/2095.4.224.1 to 95.4.239.25495.4.239.2554,094
8095.4.240.0/2095.4.240.1 to 95.4.255.25495.4.255.2554,094
8195.5.0.0/2095.5.0.1 to 95.5.15.25495.5.15.2554,094
8295.5.16.0/2095.5.16.1 to 95.5.31.25495.5.31.2554,094
8395.5.32.0/2095.5.32.1 to 95.5.47.25495.5.47.2554,094
8495.5.48.0/2095.5.48.1 to 95.5.63.25495.5.63.2554,094
8595.5.64.0/2095.5.64.1 to 95.5.79.25495.5.79.2554,094
8695.5.80.0/2095.5.80.1 to 95.5.95.25495.5.95.2554,094
8795.5.96.0/2095.5.96.1 to 95.5.111.25495.5.111.2554,094
8895.5.112.0/2095.5.112.1 to 95.5.127.25495.5.127.2554,094
8995.5.128.0/2095.5.128.1 to 95.5.143.25495.5.143.2554,094
9095.5.144.0/2095.5.144.1 to 95.5.159.25495.5.159.2554,094
9195.5.160.0/2095.5.160.1 to 95.5.175.25495.5.175.2554,094
9295.5.176.0/2095.5.176.1 to 95.5.191.25495.5.191.2554,094
9395.5.192.0/2095.5.192.1 to 95.5.207.25495.5.207.2554,094
9495.5.208.0/2095.5.208.1 to 95.5.223.25495.5.223.2554,094
9595.5.224.0/2095.5.224.1 to 95.5.239.25495.5.239.2554,094
9695.5.240.0/2095.5.240.1 to 95.5.255.25495.5.255.2554,094
9795.6.0.0/2095.6.0.1 to 95.6.15.25495.6.15.2554,094
9895.6.16.0/2095.6.16.1 to 95.6.31.25495.6.31.2554,094
9995.6.32.0/2095.6.32.1 to 95.6.47.25495.6.47.2554,094
10095.6.48.0/2095.6.48.1 to 95.6.63.25495.6.63.2554,094
10195.6.64.0/2095.6.64.1 to 95.6.79.25495.6.79.2554,094
10295.6.80.0/2095.6.80.1 to 95.6.95.25495.6.95.2554,094
10395.6.96.0/2095.6.96.1 to 95.6.111.25495.6.111.2554,094
10495.6.112.0/2095.6.112.1 to 95.6.127.25495.6.127.2554,094
10595.6.128.0/2095.6.128.1 to 95.6.143.25495.6.143.2554,094
10695.6.144.0/2095.6.144.1 to 95.6.159.25495.6.159.2554,094
10795.6.160.0/2095.6.160.1 to 95.6.175.25495.6.175.2554,094
10895.6.176.0/2095.6.176.1 to 95.6.191.25495.6.191.2554,094
10995.6.192.0/2095.6.192.1 to 95.6.207.25495.6.207.2554,094
11095.6.208.0/2095.6.208.1 to 95.6.223.25495.6.223.2554,094
11195.6.224.0/2095.6.224.1 to 95.6.239.25495.6.239.2554,094
11295.6.240.0/2095.6.240.1 to 95.6.255.25495.6.255.2554,094
11395.7.0.0/2095.7.0.1 to 95.7.15.25495.7.15.2554,094
11495.7.16.0/2095.7.16.1 to 95.7.31.25495.7.31.2554,094
11595.7.32.0/2095.7.32.1 to 95.7.47.25495.7.47.2554,094
11695.7.48.0/2095.7.48.1 to 95.7.63.25495.7.63.2554,094
11795.7.64.0/2095.7.64.1 to 95.7.79.25495.7.79.2554,094
11895.7.80.0/2095.7.80.1 to 95.7.95.25495.7.95.2554,094
11995.7.96.0/2095.7.96.1 to 95.7.111.25495.7.111.2554,094
12095.7.112.0/2095.7.112.1 to 95.7.127.25495.7.127.2554,094
12195.7.128.0/2095.7.128.1 to 95.7.143.25495.7.143.2554,094
12295.7.144.0/2095.7.144.1 to 95.7.159.25495.7.159.2554,094
12395.7.160.0/2095.7.160.1 to 95.7.175.25495.7.175.2554,094
12495.7.176.0/2095.7.176.1 to 95.7.191.25495.7.191.2554,094
12595.7.192.0/2095.7.192.1 to 95.7.207.25495.7.207.2554,094
12695.7.208.0/2095.7.208.1 to 95.7.223.25495.7.223.2554,094
12795.7.224.0/2095.7.224.1 to 95.7.239.25495.7.239.2554,094
12895.7.240.0/2095.7.240.1 to 95.7.255.25495.7.255.2554,094
12995.8.0.0/2095.8.0.1 to 95.8.15.25495.8.15.2554,094
13095.8.16.0/2095.8.16.1 to 95.8.31.25495.8.31.2554,094
13195.8.32.0/2095.8.32.1 to 95.8.47.25495.8.47.2554,094
13295.8.48.0/2095.8.48.1 to 95.8.63.25495.8.63.2554,094
13395.8.64.0/2095.8.64.1 to 95.8.79.25495.8.79.2554,094
13495.8.80.0/2095.8.80.1 to 95.8.95.25495.8.95.2554,094
13595.8.96.0/2095.8.96.1 to 95.8.111.25495.8.111.2554,094
13695.8.112.0/2095.8.112.1 to 95.8.127.25495.8.127.2554,094
13795.8.128.0/2095.8.128.1 to 95.8.143.25495.8.143.2554,094
13895.8.144.0/2095.8.144.1 to 95.8.159.25495.8.159.2554,094
13995.8.160.0/2095.8.160.1 to 95.8.175.25495.8.175.2554,094
14095.8.176.0/2095.8.176.1 to 95.8.191.25495.8.191.2554,094
14195.8.192.0/2095.8.192.1 to 95.8.207.25495.8.207.2554,094
14295.8.208.0/2095.8.208.1 to 95.8.223.25495.8.223.2554,094
14395.8.224.0/2095.8.224.1 to 95.8.239.25495.8.239.2554,094
14495.8.240.0/2095.8.240.1 to 95.8.255.25495.8.255.2554,094
14595.9.0.0/2095.9.0.1 to 95.9.15.25495.9.15.2554,094
14695.9.16.0/2095.9.16.1 to 95.9.31.25495.9.31.2554,094
14795.9.32.0/2095.9.32.1 to 95.9.47.25495.9.47.2554,094
14895.9.48.0/2095.9.48.1 to 95.9.63.25495.9.63.2554,094
14995.9.64.0/2095.9.64.1 to 95.9.79.25495.9.79.2554,094
15095.9.80.0/2095.9.80.1 to 95.9.95.25495.9.95.2554,094
15195.9.96.0/2095.9.96.1 to 95.9.111.25495.9.111.2554,094
15295.9.112.0/2095.9.112.1 to 95.9.127.25495.9.127.2554,094
15395.9.128.0/2095.9.128.1 to 95.9.143.25495.9.143.2554,094
15495.9.144.0/2095.9.144.1 to 95.9.159.25495.9.159.2554,094
15595.9.160.0/2095.9.160.1 to 95.9.175.25495.9.175.2554,094
15695.9.176.0/2095.9.176.1 to 95.9.191.25495.9.191.2554,094
15795.9.192.0/2095.9.192.1 to 95.9.207.25495.9.207.2554,094
15895.9.208.0/2095.9.208.1 to 95.9.223.25495.9.223.2554,094
15995.9.224.0/2095.9.224.1 to 95.9.239.25495.9.239.2554,094
16095.9.240.0/2095.9.240.1 to 95.9.255.25495.9.255.2554,094
16195.10.0.0/2095.10.0.1 to 95.10.15.25495.10.15.2554,094
16295.10.16.0/2095.10.16.1 to 95.10.31.25495.10.31.2554,094
16395.10.32.0/2095.10.32.1 to 95.10.47.25495.10.47.2554,094
16495.10.48.0/2095.10.48.1 to 95.10.63.25495.10.63.2554,094
16595.10.64.0/2095.10.64.1 to 95.10.79.25495.10.79.2554,094
16695.10.80.0/2095.10.80.1 to 95.10.95.25495.10.95.2554,094
16795.10.96.0/2095.10.96.1 to 95.10.111.25495.10.111.2554,094
16895.10.112.0/2095.10.112.1 to 95.10.127.25495.10.127.2554,094
16995.10.128.0/2095.10.128.1 to 95.10.143.25495.10.143.2554,094
17095.10.144.0/2095.10.144.1 to 95.10.159.25495.10.159.2554,094
17195.10.160.0/2095.10.160.1 to 95.10.175.25495.10.175.2554,094
17295.10.176.0/2095.10.176.1 to 95.10.191.25495.10.191.2554,094
17395.10.192.0/2095.10.192.1 to 95.10.207.25495.10.207.2554,094
17495.10.208.0/2095.10.208.1 to 95.10.223.25495.10.223.2554,094
17595.10.224.0/2095.10.224.1 to 95.10.239.25495.10.239.2554,094
17695.10.240.0/2095.10.240.1 to 95.10.255.25495.10.255.2554,094
17795.11.0.0/2095.11.0.1 to 95.11.15.25495.11.15.2554,094
17895.11.16.0/2095.11.16.1 to 95.11.31.25495.11.31.2554,094
17995.11.32.0/2095.11.32.1 to 95.11.47.25495.11.47.2554,094
18095.11.48.0/2095.11.48.1 to 95.11.63.25495.11.63.2554,094
18195.11.64.0/2095.11.64.1 to 95.11.79.25495.11.79.2554,094
18295.11.80.0/2095.11.80.1 to 95.11.95.25495.11.95.2554,094
18395.11.96.0/2095.11.96.1 to 95.11.111.25495.11.111.2554,094
18495.11.112.0/2095.11.112.1 to 95.11.127.25495.11.127.2554,094
18595.11.128.0/2095.11.128.1 to 95.11.143.25495.11.143.2554,094
18695.11.144.0/2095.11.144.1 to 95.11.159.25495.11.159.2554,094
18795.11.160.0/2095.11.160.1 to 95.11.175.25495.11.175.2554,094
18895.11.176.0/2095.11.176.1 to 95.11.191.25495.11.191.2554,094
18995.11.192.0/2095.11.192.1 to 95.11.207.25495.11.207.2554,094
19095.11.208.0/2095.11.208.1 to 95.11.223.25495.11.223.2554,094
19195.11.224.0/2095.11.224.1 to 95.11.239.25495.11.239.2554,094
19295.11.240.0/2095.11.240.1 to 95.11.255.25495.11.255.2554,094
19395.12.0.0/2095.12.0.1 to 95.12.15.25495.12.15.2554,094
19495.12.16.0/2095.12.16.1 to 95.12.31.25495.12.31.2554,094
19595.12.32.0/2095.12.32.1 to 95.12.47.25495.12.47.2554,094
19695.12.48.0/2095.12.48.1 to 95.12.63.25495.12.63.2554,094
19795.12.64.0/2095.12.64.1 to 95.12.79.25495.12.79.2554,094
19895.12.80.0/2095.12.80.1 to 95.12.95.25495.12.95.2554,094
19995.12.96.0/2095.12.96.1 to 95.12.111.25495.12.111.2554,094
20095.12.112.0/2095.12.112.1 to 95.12.127.25495.12.127.2554,094
20195.12.128.0/2095.12.128.1 to 95.12.143.25495.12.143.2554,094
20295.12.144.0/2095.12.144.1 to 95.12.159.25495.12.159.2554,094
20395.12.160.0/2095.12.160.1 to 95.12.175.25495.12.175.2554,094
20495.12.176.0/2095.12.176.1 to 95.12.191.25495.12.191.2554,094
20595.12.192.0/2095.12.192.1 to 95.12.207.25495.12.207.2554,094
20695.12.208.0/2095.12.208.1 to 95.12.223.25495.12.223.2554,094
20795.12.224.0/2095.12.224.1 to 95.12.239.25495.12.239.2554,094
20895.12.240.0/2095.12.240.1 to 95.12.255.25495.12.255.2554,094
20995.13.0.0/2095.13.0.1 to 95.13.15.25495.13.15.2554,094
21095.13.16.0/2095.13.16.1 to 95.13.31.25495.13.31.2554,094
21195.13.32.0/2095.13.32.1 to 95.13.47.25495.13.47.2554,094
21295.13.48.0/2095.13.48.1 to 95.13.63.25495.13.63.2554,094
21395.13.64.0/2095.13.64.1 to 95.13.79.25495.13.79.2554,094
21495.13.80.0/2095.13.80.1 to 95.13.95.25495.13.95.2554,094
21595.13.96.0/2095.13.96.1 to 95.13.111.25495.13.111.2554,094
21695.13.112.0/2095.13.112.1 to 95.13.127.25495.13.127.2554,094
21795.13.128.0/2095.13.128.1 to 95.13.143.25495.13.143.2554,094
21895.13.144.0/2095.13.144.1 to 95.13.159.25495.13.159.2554,094
21995.13.160.0/2095.13.160.1 to 95.13.175.25495.13.175.2554,094
22095.13.176.0/2095.13.176.1 to 95.13.191.25495.13.191.2554,094
22195.13.192.0/2095.13.192.1 to 95.13.207.25495.13.207.2554,094
22295.13.208.0/2095.13.208.1 to 95.13.223.25495.13.223.2554,094
22395.13.224.0/2095.13.224.1 to 95.13.239.25495.13.239.2554,094
22495.13.240.0/2095.13.240.1 to 95.13.255.25495.13.255.2554,094
22595.14.0.0/2095.14.0.1 to 95.14.15.25495.14.15.2554,094
22695.14.16.0/2095.14.16.1 to 95.14.31.25495.14.31.2554,094
22795.14.32.0/2095.14.32.1 to 95.14.47.25495.14.47.2554,094
22895.14.48.0/2095.14.48.1 to 95.14.63.25495.14.63.2554,094
22995.14.64.0/2095.14.64.1 to 95.14.79.25495.14.79.2554,094
23095.14.80.0/2095.14.80.1 to 95.14.95.25495.14.95.2554,094
23195.14.96.0/2095.14.96.1 to 95.14.111.25495.14.111.2554,094
23295.14.112.0/2095.14.112.1 to 95.14.127.25495.14.127.2554,094
23395.14.128.0/2095.14.128.1 to 95.14.143.25495.14.143.2554,094
23495.14.144.0/2095.14.144.1 to 95.14.159.25495.14.159.2554,094
23595.14.160.0/2095.14.160.1 to 95.14.175.25495.14.175.2554,094
23695.14.176.0/2095.14.176.1 to 95.14.191.25495.14.191.2554,094
23795.14.192.0/2095.14.192.1 to 95.14.207.25495.14.207.2554,094
23895.14.208.0/2095.14.208.1 to 95.14.223.25495.14.223.2554,094
23995.14.224.0/2095.14.224.1 to 95.14.239.25495.14.239.2554,094
24095.14.240.0/2095.14.240.1 to 95.14.255.25495.14.255.2554,094
24195.15.0.0/2095.15.0.1 to 95.15.15.25495.15.15.2554,094
24295.15.16.0/2095.15.16.1 to 95.15.31.25495.15.31.2554,094
24395.15.32.0/2095.15.32.1 to 95.15.47.25495.15.47.2554,094
24495.15.48.0/2095.15.48.1 to 95.15.63.25495.15.63.2554,094
24595.15.64.0/2095.15.64.1 to 95.15.79.25495.15.79.2554,094
24695.15.80.0/2095.15.80.1 to 95.15.95.25495.15.95.2554,094
24795.15.96.0/2095.15.96.1 to 95.15.111.25495.15.111.2554,094
24895.15.112.0/2095.15.112.1 to 95.15.127.25495.15.127.2554,094
24995.15.128.0/2095.15.128.1 to 95.15.143.25495.15.143.2554,094
25095.15.144.0/2095.15.144.1 to 95.15.159.25495.15.159.2554,094
25195.15.160.0/2095.15.160.1 to 95.15.175.25495.15.175.2554,094
25295.15.176.0/2095.15.176.1 to 95.15.191.25495.15.191.2554,094
25395.15.192.0/2095.15.192.1 to 95.15.207.25495.15.207.2554,094
25495.15.208.0/2095.15.208.1 to 95.15.223.25495.15.223.2554,094
25595.15.224.0/2095.15.224.1 to 95.15.239.25495.15.239.2554,094
25695.15.240.0/2095.15.240.1 to 95.15.255.25495.15.255.2554,094

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.