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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.

Network26.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
26.0.0.0
Broadcast address
26.255.255.255
First usable
26.0.0.1
Last usable
26.255.255.254
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 1A000000 · Integer 436207616 to 452984831
Reverse DNS zone
26.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00011010..00000000.00000000.0000000026.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00011010..00000000.00000000.0000000026.0.0.0
Broadcast00011010..11111111.11111111.1111111126.255.255.255
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)

26.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
126.0.0.0/2026.0.0.1 to 26.0.15.25426.0.15.2554,094
226.0.16.0/2026.0.16.1 to 26.0.31.25426.0.31.2554,094
326.0.32.0/2026.0.32.1 to 26.0.47.25426.0.47.2554,094
426.0.48.0/2026.0.48.1 to 26.0.63.25426.0.63.2554,094
526.0.64.0/2026.0.64.1 to 26.0.79.25426.0.79.2554,094
626.0.80.0/2026.0.80.1 to 26.0.95.25426.0.95.2554,094
726.0.96.0/2026.0.96.1 to 26.0.111.25426.0.111.2554,094
826.0.112.0/2026.0.112.1 to 26.0.127.25426.0.127.2554,094
926.0.128.0/2026.0.128.1 to 26.0.143.25426.0.143.2554,094
1026.0.144.0/2026.0.144.1 to 26.0.159.25426.0.159.2554,094
1126.0.160.0/2026.0.160.1 to 26.0.175.25426.0.175.2554,094
1226.0.176.0/2026.0.176.1 to 26.0.191.25426.0.191.2554,094
1326.0.192.0/2026.0.192.1 to 26.0.207.25426.0.207.2554,094
1426.0.208.0/2026.0.208.1 to 26.0.223.25426.0.223.2554,094
1526.0.224.0/2026.0.224.1 to 26.0.239.25426.0.239.2554,094
1626.0.240.0/2026.0.240.1 to 26.0.255.25426.0.255.2554,094
1726.1.0.0/2026.1.0.1 to 26.1.15.25426.1.15.2554,094
1826.1.16.0/2026.1.16.1 to 26.1.31.25426.1.31.2554,094
1926.1.32.0/2026.1.32.1 to 26.1.47.25426.1.47.2554,094
2026.1.48.0/2026.1.48.1 to 26.1.63.25426.1.63.2554,094
2126.1.64.0/2026.1.64.1 to 26.1.79.25426.1.79.2554,094
2226.1.80.0/2026.1.80.1 to 26.1.95.25426.1.95.2554,094
2326.1.96.0/2026.1.96.1 to 26.1.111.25426.1.111.2554,094
2426.1.112.0/2026.1.112.1 to 26.1.127.25426.1.127.2554,094
2526.1.128.0/2026.1.128.1 to 26.1.143.25426.1.143.2554,094
2626.1.144.0/2026.1.144.1 to 26.1.159.25426.1.159.2554,094
2726.1.160.0/2026.1.160.1 to 26.1.175.25426.1.175.2554,094
2826.1.176.0/2026.1.176.1 to 26.1.191.25426.1.191.2554,094
2926.1.192.0/2026.1.192.1 to 26.1.207.25426.1.207.2554,094
3026.1.208.0/2026.1.208.1 to 26.1.223.25426.1.223.2554,094
3126.1.224.0/2026.1.224.1 to 26.1.239.25426.1.239.2554,094
3226.1.240.0/2026.1.240.1 to 26.1.255.25426.1.255.2554,094
3326.2.0.0/2026.2.0.1 to 26.2.15.25426.2.15.2554,094
3426.2.16.0/2026.2.16.1 to 26.2.31.25426.2.31.2554,094
3526.2.32.0/2026.2.32.1 to 26.2.47.25426.2.47.2554,094
3626.2.48.0/2026.2.48.1 to 26.2.63.25426.2.63.2554,094
3726.2.64.0/2026.2.64.1 to 26.2.79.25426.2.79.2554,094
3826.2.80.0/2026.2.80.1 to 26.2.95.25426.2.95.2554,094
3926.2.96.0/2026.2.96.1 to 26.2.111.25426.2.111.2554,094
4026.2.112.0/2026.2.112.1 to 26.2.127.25426.2.127.2554,094
4126.2.128.0/2026.2.128.1 to 26.2.143.25426.2.143.2554,094
4226.2.144.0/2026.2.144.1 to 26.2.159.25426.2.159.2554,094
4326.2.160.0/2026.2.160.1 to 26.2.175.25426.2.175.2554,094
4426.2.176.0/2026.2.176.1 to 26.2.191.25426.2.191.2554,094
4526.2.192.0/2026.2.192.1 to 26.2.207.25426.2.207.2554,094
4626.2.208.0/2026.2.208.1 to 26.2.223.25426.2.223.2554,094
4726.2.224.0/2026.2.224.1 to 26.2.239.25426.2.239.2554,094
4826.2.240.0/2026.2.240.1 to 26.2.255.25426.2.255.2554,094
4926.3.0.0/2026.3.0.1 to 26.3.15.25426.3.15.2554,094
5026.3.16.0/2026.3.16.1 to 26.3.31.25426.3.31.2554,094
5126.3.32.0/2026.3.32.1 to 26.3.47.25426.3.47.2554,094
5226.3.48.0/2026.3.48.1 to 26.3.63.25426.3.63.2554,094
5326.3.64.0/2026.3.64.1 to 26.3.79.25426.3.79.2554,094
5426.3.80.0/2026.3.80.1 to 26.3.95.25426.3.95.2554,094
5526.3.96.0/2026.3.96.1 to 26.3.111.25426.3.111.2554,094
5626.3.112.0/2026.3.112.1 to 26.3.127.25426.3.127.2554,094
5726.3.128.0/2026.3.128.1 to 26.3.143.25426.3.143.2554,094
5826.3.144.0/2026.3.144.1 to 26.3.159.25426.3.159.2554,094
5926.3.160.0/2026.3.160.1 to 26.3.175.25426.3.175.2554,094
6026.3.176.0/2026.3.176.1 to 26.3.191.25426.3.191.2554,094
6126.3.192.0/2026.3.192.1 to 26.3.207.25426.3.207.2554,094
6226.3.208.0/2026.3.208.1 to 26.3.223.25426.3.223.2554,094
6326.3.224.0/2026.3.224.1 to 26.3.239.25426.3.239.2554,094
6426.3.240.0/2026.3.240.1 to 26.3.255.25426.3.255.2554,094
6526.4.0.0/2026.4.0.1 to 26.4.15.25426.4.15.2554,094
6626.4.16.0/2026.4.16.1 to 26.4.31.25426.4.31.2554,094
6726.4.32.0/2026.4.32.1 to 26.4.47.25426.4.47.2554,094
6826.4.48.0/2026.4.48.1 to 26.4.63.25426.4.63.2554,094
6926.4.64.0/2026.4.64.1 to 26.4.79.25426.4.79.2554,094
7026.4.80.0/2026.4.80.1 to 26.4.95.25426.4.95.2554,094
7126.4.96.0/2026.4.96.1 to 26.4.111.25426.4.111.2554,094
7226.4.112.0/2026.4.112.1 to 26.4.127.25426.4.127.2554,094
7326.4.128.0/2026.4.128.1 to 26.4.143.25426.4.143.2554,094
7426.4.144.0/2026.4.144.1 to 26.4.159.25426.4.159.2554,094
7526.4.160.0/2026.4.160.1 to 26.4.175.25426.4.175.2554,094
7626.4.176.0/2026.4.176.1 to 26.4.191.25426.4.191.2554,094
7726.4.192.0/2026.4.192.1 to 26.4.207.25426.4.207.2554,094
7826.4.208.0/2026.4.208.1 to 26.4.223.25426.4.223.2554,094
7926.4.224.0/2026.4.224.1 to 26.4.239.25426.4.239.2554,094
8026.4.240.0/2026.4.240.1 to 26.4.255.25426.4.255.2554,094
8126.5.0.0/2026.5.0.1 to 26.5.15.25426.5.15.2554,094
8226.5.16.0/2026.5.16.1 to 26.5.31.25426.5.31.2554,094
8326.5.32.0/2026.5.32.1 to 26.5.47.25426.5.47.2554,094
8426.5.48.0/2026.5.48.1 to 26.5.63.25426.5.63.2554,094
8526.5.64.0/2026.5.64.1 to 26.5.79.25426.5.79.2554,094
8626.5.80.0/2026.5.80.1 to 26.5.95.25426.5.95.2554,094
8726.5.96.0/2026.5.96.1 to 26.5.111.25426.5.111.2554,094
8826.5.112.0/2026.5.112.1 to 26.5.127.25426.5.127.2554,094
8926.5.128.0/2026.5.128.1 to 26.5.143.25426.5.143.2554,094
9026.5.144.0/2026.5.144.1 to 26.5.159.25426.5.159.2554,094
9126.5.160.0/2026.5.160.1 to 26.5.175.25426.5.175.2554,094
9226.5.176.0/2026.5.176.1 to 26.5.191.25426.5.191.2554,094
9326.5.192.0/2026.5.192.1 to 26.5.207.25426.5.207.2554,094
9426.5.208.0/2026.5.208.1 to 26.5.223.25426.5.223.2554,094
9526.5.224.0/2026.5.224.1 to 26.5.239.25426.5.239.2554,094
9626.5.240.0/2026.5.240.1 to 26.5.255.25426.5.255.2554,094
9726.6.0.0/2026.6.0.1 to 26.6.15.25426.6.15.2554,094
9826.6.16.0/2026.6.16.1 to 26.6.31.25426.6.31.2554,094
9926.6.32.0/2026.6.32.1 to 26.6.47.25426.6.47.2554,094
10026.6.48.0/2026.6.48.1 to 26.6.63.25426.6.63.2554,094
10126.6.64.0/2026.6.64.1 to 26.6.79.25426.6.79.2554,094
10226.6.80.0/2026.6.80.1 to 26.6.95.25426.6.95.2554,094
10326.6.96.0/2026.6.96.1 to 26.6.111.25426.6.111.2554,094
10426.6.112.0/2026.6.112.1 to 26.6.127.25426.6.127.2554,094
10526.6.128.0/2026.6.128.1 to 26.6.143.25426.6.143.2554,094
10626.6.144.0/2026.6.144.1 to 26.6.159.25426.6.159.2554,094
10726.6.160.0/2026.6.160.1 to 26.6.175.25426.6.175.2554,094
10826.6.176.0/2026.6.176.1 to 26.6.191.25426.6.191.2554,094
10926.6.192.0/2026.6.192.1 to 26.6.207.25426.6.207.2554,094
11026.6.208.0/2026.6.208.1 to 26.6.223.25426.6.223.2554,094
11126.6.224.0/2026.6.224.1 to 26.6.239.25426.6.239.2554,094
11226.6.240.0/2026.6.240.1 to 26.6.255.25426.6.255.2554,094
11326.7.0.0/2026.7.0.1 to 26.7.15.25426.7.15.2554,094
11426.7.16.0/2026.7.16.1 to 26.7.31.25426.7.31.2554,094
11526.7.32.0/2026.7.32.1 to 26.7.47.25426.7.47.2554,094
11626.7.48.0/2026.7.48.1 to 26.7.63.25426.7.63.2554,094
11726.7.64.0/2026.7.64.1 to 26.7.79.25426.7.79.2554,094
11826.7.80.0/2026.7.80.1 to 26.7.95.25426.7.95.2554,094
11926.7.96.0/2026.7.96.1 to 26.7.111.25426.7.111.2554,094
12026.7.112.0/2026.7.112.1 to 26.7.127.25426.7.127.2554,094
12126.7.128.0/2026.7.128.1 to 26.7.143.25426.7.143.2554,094
12226.7.144.0/2026.7.144.1 to 26.7.159.25426.7.159.2554,094
12326.7.160.0/2026.7.160.1 to 26.7.175.25426.7.175.2554,094
12426.7.176.0/2026.7.176.1 to 26.7.191.25426.7.191.2554,094
12526.7.192.0/2026.7.192.1 to 26.7.207.25426.7.207.2554,094
12626.7.208.0/2026.7.208.1 to 26.7.223.25426.7.223.2554,094
12726.7.224.0/2026.7.224.1 to 26.7.239.25426.7.239.2554,094
12826.7.240.0/2026.7.240.1 to 26.7.255.25426.7.255.2554,094
12926.8.0.0/2026.8.0.1 to 26.8.15.25426.8.15.2554,094
13026.8.16.0/2026.8.16.1 to 26.8.31.25426.8.31.2554,094
13126.8.32.0/2026.8.32.1 to 26.8.47.25426.8.47.2554,094
13226.8.48.0/2026.8.48.1 to 26.8.63.25426.8.63.2554,094
13326.8.64.0/2026.8.64.1 to 26.8.79.25426.8.79.2554,094
13426.8.80.0/2026.8.80.1 to 26.8.95.25426.8.95.2554,094
13526.8.96.0/2026.8.96.1 to 26.8.111.25426.8.111.2554,094
13626.8.112.0/2026.8.112.1 to 26.8.127.25426.8.127.2554,094
13726.8.128.0/2026.8.128.1 to 26.8.143.25426.8.143.2554,094
13826.8.144.0/2026.8.144.1 to 26.8.159.25426.8.159.2554,094
13926.8.160.0/2026.8.160.1 to 26.8.175.25426.8.175.2554,094
14026.8.176.0/2026.8.176.1 to 26.8.191.25426.8.191.2554,094
14126.8.192.0/2026.8.192.1 to 26.8.207.25426.8.207.2554,094
14226.8.208.0/2026.8.208.1 to 26.8.223.25426.8.223.2554,094
14326.8.224.0/2026.8.224.1 to 26.8.239.25426.8.239.2554,094
14426.8.240.0/2026.8.240.1 to 26.8.255.25426.8.255.2554,094
14526.9.0.0/2026.9.0.1 to 26.9.15.25426.9.15.2554,094
14626.9.16.0/2026.9.16.1 to 26.9.31.25426.9.31.2554,094
14726.9.32.0/2026.9.32.1 to 26.9.47.25426.9.47.2554,094
14826.9.48.0/2026.9.48.1 to 26.9.63.25426.9.63.2554,094
14926.9.64.0/2026.9.64.1 to 26.9.79.25426.9.79.2554,094
15026.9.80.0/2026.9.80.1 to 26.9.95.25426.9.95.2554,094
15126.9.96.0/2026.9.96.1 to 26.9.111.25426.9.111.2554,094
15226.9.112.0/2026.9.112.1 to 26.9.127.25426.9.127.2554,094
15326.9.128.0/2026.9.128.1 to 26.9.143.25426.9.143.2554,094
15426.9.144.0/2026.9.144.1 to 26.9.159.25426.9.159.2554,094
15526.9.160.0/2026.9.160.1 to 26.9.175.25426.9.175.2554,094
15626.9.176.0/2026.9.176.1 to 26.9.191.25426.9.191.2554,094
15726.9.192.0/2026.9.192.1 to 26.9.207.25426.9.207.2554,094
15826.9.208.0/2026.9.208.1 to 26.9.223.25426.9.223.2554,094
15926.9.224.0/2026.9.224.1 to 26.9.239.25426.9.239.2554,094
16026.9.240.0/2026.9.240.1 to 26.9.255.25426.9.255.2554,094
16126.10.0.0/2026.10.0.1 to 26.10.15.25426.10.15.2554,094
16226.10.16.0/2026.10.16.1 to 26.10.31.25426.10.31.2554,094
16326.10.32.0/2026.10.32.1 to 26.10.47.25426.10.47.2554,094
16426.10.48.0/2026.10.48.1 to 26.10.63.25426.10.63.2554,094
16526.10.64.0/2026.10.64.1 to 26.10.79.25426.10.79.2554,094
16626.10.80.0/2026.10.80.1 to 26.10.95.25426.10.95.2554,094
16726.10.96.0/2026.10.96.1 to 26.10.111.25426.10.111.2554,094
16826.10.112.0/2026.10.112.1 to 26.10.127.25426.10.127.2554,094
16926.10.128.0/2026.10.128.1 to 26.10.143.25426.10.143.2554,094
17026.10.144.0/2026.10.144.1 to 26.10.159.25426.10.159.2554,094
17126.10.160.0/2026.10.160.1 to 26.10.175.25426.10.175.2554,094
17226.10.176.0/2026.10.176.1 to 26.10.191.25426.10.191.2554,094
17326.10.192.0/2026.10.192.1 to 26.10.207.25426.10.207.2554,094
17426.10.208.0/2026.10.208.1 to 26.10.223.25426.10.223.2554,094
17526.10.224.0/2026.10.224.1 to 26.10.239.25426.10.239.2554,094
17626.10.240.0/2026.10.240.1 to 26.10.255.25426.10.255.2554,094
17726.11.0.0/2026.11.0.1 to 26.11.15.25426.11.15.2554,094
17826.11.16.0/2026.11.16.1 to 26.11.31.25426.11.31.2554,094
17926.11.32.0/2026.11.32.1 to 26.11.47.25426.11.47.2554,094
18026.11.48.0/2026.11.48.1 to 26.11.63.25426.11.63.2554,094
18126.11.64.0/2026.11.64.1 to 26.11.79.25426.11.79.2554,094
18226.11.80.0/2026.11.80.1 to 26.11.95.25426.11.95.2554,094
18326.11.96.0/2026.11.96.1 to 26.11.111.25426.11.111.2554,094
18426.11.112.0/2026.11.112.1 to 26.11.127.25426.11.127.2554,094
18526.11.128.0/2026.11.128.1 to 26.11.143.25426.11.143.2554,094
18626.11.144.0/2026.11.144.1 to 26.11.159.25426.11.159.2554,094
18726.11.160.0/2026.11.160.1 to 26.11.175.25426.11.175.2554,094
18826.11.176.0/2026.11.176.1 to 26.11.191.25426.11.191.2554,094
18926.11.192.0/2026.11.192.1 to 26.11.207.25426.11.207.2554,094
19026.11.208.0/2026.11.208.1 to 26.11.223.25426.11.223.2554,094
19126.11.224.0/2026.11.224.1 to 26.11.239.25426.11.239.2554,094
19226.11.240.0/2026.11.240.1 to 26.11.255.25426.11.255.2554,094
19326.12.0.0/2026.12.0.1 to 26.12.15.25426.12.15.2554,094
19426.12.16.0/2026.12.16.1 to 26.12.31.25426.12.31.2554,094
19526.12.32.0/2026.12.32.1 to 26.12.47.25426.12.47.2554,094
19626.12.48.0/2026.12.48.1 to 26.12.63.25426.12.63.2554,094
19726.12.64.0/2026.12.64.1 to 26.12.79.25426.12.79.2554,094
19826.12.80.0/2026.12.80.1 to 26.12.95.25426.12.95.2554,094
19926.12.96.0/2026.12.96.1 to 26.12.111.25426.12.111.2554,094
20026.12.112.0/2026.12.112.1 to 26.12.127.25426.12.127.2554,094
20126.12.128.0/2026.12.128.1 to 26.12.143.25426.12.143.2554,094
20226.12.144.0/2026.12.144.1 to 26.12.159.25426.12.159.2554,094
20326.12.160.0/2026.12.160.1 to 26.12.175.25426.12.175.2554,094
20426.12.176.0/2026.12.176.1 to 26.12.191.25426.12.191.2554,094
20526.12.192.0/2026.12.192.1 to 26.12.207.25426.12.207.2554,094
20626.12.208.0/2026.12.208.1 to 26.12.223.25426.12.223.2554,094
20726.12.224.0/2026.12.224.1 to 26.12.239.25426.12.239.2554,094
20826.12.240.0/2026.12.240.1 to 26.12.255.25426.12.255.2554,094
20926.13.0.0/2026.13.0.1 to 26.13.15.25426.13.15.2554,094
21026.13.16.0/2026.13.16.1 to 26.13.31.25426.13.31.2554,094
21126.13.32.0/2026.13.32.1 to 26.13.47.25426.13.47.2554,094
21226.13.48.0/2026.13.48.1 to 26.13.63.25426.13.63.2554,094
21326.13.64.0/2026.13.64.1 to 26.13.79.25426.13.79.2554,094
21426.13.80.0/2026.13.80.1 to 26.13.95.25426.13.95.2554,094
21526.13.96.0/2026.13.96.1 to 26.13.111.25426.13.111.2554,094
21626.13.112.0/2026.13.112.1 to 26.13.127.25426.13.127.2554,094
21726.13.128.0/2026.13.128.1 to 26.13.143.25426.13.143.2554,094
21826.13.144.0/2026.13.144.1 to 26.13.159.25426.13.159.2554,094
21926.13.160.0/2026.13.160.1 to 26.13.175.25426.13.175.2554,094
22026.13.176.0/2026.13.176.1 to 26.13.191.25426.13.191.2554,094
22126.13.192.0/2026.13.192.1 to 26.13.207.25426.13.207.2554,094
22226.13.208.0/2026.13.208.1 to 26.13.223.25426.13.223.2554,094
22326.13.224.0/2026.13.224.1 to 26.13.239.25426.13.239.2554,094
22426.13.240.0/2026.13.240.1 to 26.13.255.25426.13.255.2554,094
22526.14.0.0/2026.14.0.1 to 26.14.15.25426.14.15.2554,094
22626.14.16.0/2026.14.16.1 to 26.14.31.25426.14.31.2554,094
22726.14.32.0/2026.14.32.1 to 26.14.47.25426.14.47.2554,094
22826.14.48.0/2026.14.48.1 to 26.14.63.25426.14.63.2554,094
22926.14.64.0/2026.14.64.1 to 26.14.79.25426.14.79.2554,094
23026.14.80.0/2026.14.80.1 to 26.14.95.25426.14.95.2554,094
23126.14.96.0/2026.14.96.1 to 26.14.111.25426.14.111.2554,094
23226.14.112.0/2026.14.112.1 to 26.14.127.25426.14.127.2554,094
23326.14.128.0/2026.14.128.1 to 26.14.143.25426.14.143.2554,094
23426.14.144.0/2026.14.144.1 to 26.14.159.25426.14.159.2554,094
23526.14.160.0/2026.14.160.1 to 26.14.175.25426.14.175.2554,094
23626.14.176.0/2026.14.176.1 to 26.14.191.25426.14.191.2554,094
23726.14.192.0/2026.14.192.1 to 26.14.207.25426.14.207.2554,094
23826.14.208.0/2026.14.208.1 to 26.14.223.25426.14.223.2554,094
23926.14.224.0/2026.14.224.1 to 26.14.239.25426.14.239.2554,094
24026.14.240.0/2026.14.240.1 to 26.14.255.25426.14.255.2554,094
24126.15.0.0/2026.15.0.1 to 26.15.15.25426.15.15.2554,094
24226.15.16.0/2026.15.16.1 to 26.15.31.25426.15.31.2554,094
24326.15.32.0/2026.15.32.1 to 26.15.47.25426.15.47.2554,094
24426.15.48.0/2026.15.48.1 to 26.15.63.25426.15.63.2554,094
24526.15.64.0/2026.15.64.1 to 26.15.79.25426.15.79.2554,094
24626.15.80.0/2026.15.80.1 to 26.15.95.25426.15.95.2554,094
24726.15.96.0/2026.15.96.1 to 26.15.111.25426.15.111.2554,094
24826.15.112.0/2026.15.112.1 to 26.15.127.25426.15.127.2554,094
24926.15.128.0/2026.15.128.1 to 26.15.143.25426.15.143.2554,094
25026.15.144.0/2026.15.144.1 to 26.15.159.25426.15.159.2554,094
25126.15.160.0/2026.15.160.1 to 26.15.175.25426.15.175.2554,094
25226.15.176.0/2026.15.176.1 to 26.15.191.25426.15.191.2554,094
25326.15.192.0/2026.15.192.1 to 26.15.207.25426.15.207.2554,094
25426.15.208.0/2026.15.208.1 to 26.15.223.25426.15.223.2554,094
25526.15.224.0/2026.15.224.1 to 26.15.239.25426.15.239.2554,094
25626.15.240.0/2026.15.240.1 to 26.15.255.25426.15.255.2554,094

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.