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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.

Network70.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
70.0.0.0
Broadcast address
70.255.255.255
First usable
70.0.0.1
Last usable
70.255.255.254
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 46000000 · Integer 1174405120 to 1191182335
Reverse DNS zone
70.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000110..00000000.00000000.0000000070.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01000110..00000000.00000000.0000000070.0.0.0
Broadcast01000110..11111111.11111111.1111111170.255.255.255
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)

70.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
170.0.0.0/2070.0.0.1 to 70.0.15.25470.0.15.2554,094
270.0.16.0/2070.0.16.1 to 70.0.31.25470.0.31.2554,094
370.0.32.0/2070.0.32.1 to 70.0.47.25470.0.47.2554,094
470.0.48.0/2070.0.48.1 to 70.0.63.25470.0.63.2554,094
570.0.64.0/2070.0.64.1 to 70.0.79.25470.0.79.2554,094
670.0.80.0/2070.0.80.1 to 70.0.95.25470.0.95.2554,094
770.0.96.0/2070.0.96.1 to 70.0.111.25470.0.111.2554,094
870.0.112.0/2070.0.112.1 to 70.0.127.25470.0.127.2554,094
970.0.128.0/2070.0.128.1 to 70.0.143.25470.0.143.2554,094
1070.0.144.0/2070.0.144.1 to 70.0.159.25470.0.159.2554,094
1170.0.160.0/2070.0.160.1 to 70.0.175.25470.0.175.2554,094
1270.0.176.0/2070.0.176.1 to 70.0.191.25470.0.191.2554,094
1370.0.192.0/2070.0.192.1 to 70.0.207.25470.0.207.2554,094
1470.0.208.0/2070.0.208.1 to 70.0.223.25470.0.223.2554,094
1570.0.224.0/2070.0.224.1 to 70.0.239.25470.0.239.2554,094
1670.0.240.0/2070.0.240.1 to 70.0.255.25470.0.255.2554,094
1770.1.0.0/2070.1.0.1 to 70.1.15.25470.1.15.2554,094
1870.1.16.0/2070.1.16.1 to 70.1.31.25470.1.31.2554,094
1970.1.32.0/2070.1.32.1 to 70.1.47.25470.1.47.2554,094
2070.1.48.0/2070.1.48.1 to 70.1.63.25470.1.63.2554,094
2170.1.64.0/2070.1.64.1 to 70.1.79.25470.1.79.2554,094
2270.1.80.0/2070.1.80.1 to 70.1.95.25470.1.95.2554,094
2370.1.96.0/2070.1.96.1 to 70.1.111.25470.1.111.2554,094
2470.1.112.0/2070.1.112.1 to 70.1.127.25470.1.127.2554,094
2570.1.128.0/2070.1.128.1 to 70.1.143.25470.1.143.2554,094
2670.1.144.0/2070.1.144.1 to 70.1.159.25470.1.159.2554,094
2770.1.160.0/2070.1.160.1 to 70.1.175.25470.1.175.2554,094
2870.1.176.0/2070.1.176.1 to 70.1.191.25470.1.191.2554,094
2970.1.192.0/2070.1.192.1 to 70.1.207.25470.1.207.2554,094
3070.1.208.0/2070.1.208.1 to 70.1.223.25470.1.223.2554,094
3170.1.224.0/2070.1.224.1 to 70.1.239.25470.1.239.2554,094
3270.1.240.0/2070.1.240.1 to 70.1.255.25470.1.255.2554,094
3370.2.0.0/2070.2.0.1 to 70.2.15.25470.2.15.2554,094
3470.2.16.0/2070.2.16.1 to 70.2.31.25470.2.31.2554,094
3570.2.32.0/2070.2.32.1 to 70.2.47.25470.2.47.2554,094
3670.2.48.0/2070.2.48.1 to 70.2.63.25470.2.63.2554,094
3770.2.64.0/2070.2.64.1 to 70.2.79.25470.2.79.2554,094
3870.2.80.0/2070.2.80.1 to 70.2.95.25470.2.95.2554,094
3970.2.96.0/2070.2.96.1 to 70.2.111.25470.2.111.2554,094
4070.2.112.0/2070.2.112.1 to 70.2.127.25470.2.127.2554,094
4170.2.128.0/2070.2.128.1 to 70.2.143.25470.2.143.2554,094
4270.2.144.0/2070.2.144.1 to 70.2.159.25470.2.159.2554,094
4370.2.160.0/2070.2.160.1 to 70.2.175.25470.2.175.2554,094
4470.2.176.0/2070.2.176.1 to 70.2.191.25470.2.191.2554,094
4570.2.192.0/2070.2.192.1 to 70.2.207.25470.2.207.2554,094
4670.2.208.0/2070.2.208.1 to 70.2.223.25470.2.223.2554,094
4770.2.224.0/2070.2.224.1 to 70.2.239.25470.2.239.2554,094
4870.2.240.0/2070.2.240.1 to 70.2.255.25470.2.255.2554,094
4970.3.0.0/2070.3.0.1 to 70.3.15.25470.3.15.2554,094
5070.3.16.0/2070.3.16.1 to 70.3.31.25470.3.31.2554,094
5170.3.32.0/2070.3.32.1 to 70.3.47.25470.3.47.2554,094
5270.3.48.0/2070.3.48.1 to 70.3.63.25470.3.63.2554,094
5370.3.64.0/2070.3.64.1 to 70.3.79.25470.3.79.2554,094
5470.3.80.0/2070.3.80.1 to 70.3.95.25470.3.95.2554,094
5570.3.96.0/2070.3.96.1 to 70.3.111.25470.3.111.2554,094
5670.3.112.0/2070.3.112.1 to 70.3.127.25470.3.127.2554,094
5770.3.128.0/2070.3.128.1 to 70.3.143.25470.3.143.2554,094
5870.3.144.0/2070.3.144.1 to 70.3.159.25470.3.159.2554,094
5970.3.160.0/2070.3.160.1 to 70.3.175.25470.3.175.2554,094
6070.3.176.0/2070.3.176.1 to 70.3.191.25470.3.191.2554,094
6170.3.192.0/2070.3.192.1 to 70.3.207.25470.3.207.2554,094
6270.3.208.0/2070.3.208.1 to 70.3.223.25470.3.223.2554,094
6370.3.224.0/2070.3.224.1 to 70.3.239.25470.3.239.2554,094
6470.3.240.0/2070.3.240.1 to 70.3.255.25470.3.255.2554,094
6570.4.0.0/2070.4.0.1 to 70.4.15.25470.4.15.2554,094
6670.4.16.0/2070.4.16.1 to 70.4.31.25470.4.31.2554,094
6770.4.32.0/2070.4.32.1 to 70.4.47.25470.4.47.2554,094
6870.4.48.0/2070.4.48.1 to 70.4.63.25470.4.63.2554,094
6970.4.64.0/2070.4.64.1 to 70.4.79.25470.4.79.2554,094
7070.4.80.0/2070.4.80.1 to 70.4.95.25470.4.95.2554,094
7170.4.96.0/2070.4.96.1 to 70.4.111.25470.4.111.2554,094
7270.4.112.0/2070.4.112.1 to 70.4.127.25470.4.127.2554,094
7370.4.128.0/2070.4.128.1 to 70.4.143.25470.4.143.2554,094
7470.4.144.0/2070.4.144.1 to 70.4.159.25470.4.159.2554,094
7570.4.160.0/2070.4.160.1 to 70.4.175.25470.4.175.2554,094
7670.4.176.0/2070.4.176.1 to 70.4.191.25470.4.191.2554,094
7770.4.192.0/2070.4.192.1 to 70.4.207.25470.4.207.2554,094
7870.4.208.0/2070.4.208.1 to 70.4.223.25470.4.223.2554,094
7970.4.224.0/2070.4.224.1 to 70.4.239.25470.4.239.2554,094
8070.4.240.0/2070.4.240.1 to 70.4.255.25470.4.255.2554,094
8170.5.0.0/2070.5.0.1 to 70.5.15.25470.5.15.2554,094
8270.5.16.0/2070.5.16.1 to 70.5.31.25470.5.31.2554,094
8370.5.32.0/2070.5.32.1 to 70.5.47.25470.5.47.2554,094
8470.5.48.0/2070.5.48.1 to 70.5.63.25470.5.63.2554,094
8570.5.64.0/2070.5.64.1 to 70.5.79.25470.5.79.2554,094
8670.5.80.0/2070.5.80.1 to 70.5.95.25470.5.95.2554,094
8770.5.96.0/2070.5.96.1 to 70.5.111.25470.5.111.2554,094
8870.5.112.0/2070.5.112.1 to 70.5.127.25470.5.127.2554,094
8970.5.128.0/2070.5.128.1 to 70.5.143.25470.5.143.2554,094
9070.5.144.0/2070.5.144.1 to 70.5.159.25470.5.159.2554,094
9170.5.160.0/2070.5.160.1 to 70.5.175.25470.5.175.2554,094
9270.5.176.0/2070.5.176.1 to 70.5.191.25470.5.191.2554,094
9370.5.192.0/2070.5.192.1 to 70.5.207.25470.5.207.2554,094
9470.5.208.0/2070.5.208.1 to 70.5.223.25470.5.223.2554,094
9570.5.224.0/2070.5.224.1 to 70.5.239.25470.5.239.2554,094
9670.5.240.0/2070.5.240.1 to 70.5.255.25470.5.255.2554,094
9770.6.0.0/2070.6.0.1 to 70.6.15.25470.6.15.2554,094
9870.6.16.0/2070.6.16.1 to 70.6.31.25470.6.31.2554,094
9970.6.32.0/2070.6.32.1 to 70.6.47.25470.6.47.2554,094
10070.6.48.0/2070.6.48.1 to 70.6.63.25470.6.63.2554,094
10170.6.64.0/2070.6.64.1 to 70.6.79.25470.6.79.2554,094
10270.6.80.0/2070.6.80.1 to 70.6.95.25470.6.95.2554,094
10370.6.96.0/2070.6.96.1 to 70.6.111.25470.6.111.2554,094
10470.6.112.0/2070.6.112.1 to 70.6.127.25470.6.127.2554,094
10570.6.128.0/2070.6.128.1 to 70.6.143.25470.6.143.2554,094
10670.6.144.0/2070.6.144.1 to 70.6.159.25470.6.159.2554,094
10770.6.160.0/2070.6.160.1 to 70.6.175.25470.6.175.2554,094
10870.6.176.0/2070.6.176.1 to 70.6.191.25470.6.191.2554,094
10970.6.192.0/2070.6.192.1 to 70.6.207.25470.6.207.2554,094
11070.6.208.0/2070.6.208.1 to 70.6.223.25470.6.223.2554,094
11170.6.224.0/2070.6.224.1 to 70.6.239.25470.6.239.2554,094
11270.6.240.0/2070.6.240.1 to 70.6.255.25470.6.255.2554,094
11370.7.0.0/2070.7.0.1 to 70.7.15.25470.7.15.2554,094
11470.7.16.0/2070.7.16.1 to 70.7.31.25470.7.31.2554,094
11570.7.32.0/2070.7.32.1 to 70.7.47.25470.7.47.2554,094
11670.7.48.0/2070.7.48.1 to 70.7.63.25470.7.63.2554,094
11770.7.64.0/2070.7.64.1 to 70.7.79.25470.7.79.2554,094
11870.7.80.0/2070.7.80.1 to 70.7.95.25470.7.95.2554,094
11970.7.96.0/2070.7.96.1 to 70.7.111.25470.7.111.2554,094
12070.7.112.0/2070.7.112.1 to 70.7.127.25470.7.127.2554,094
12170.7.128.0/2070.7.128.1 to 70.7.143.25470.7.143.2554,094
12270.7.144.0/2070.7.144.1 to 70.7.159.25470.7.159.2554,094
12370.7.160.0/2070.7.160.1 to 70.7.175.25470.7.175.2554,094
12470.7.176.0/2070.7.176.1 to 70.7.191.25470.7.191.2554,094
12570.7.192.0/2070.7.192.1 to 70.7.207.25470.7.207.2554,094
12670.7.208.0/2070.7.208.1 to 70.7.223.25470.7.223.2554,094
12770.7.224.0/2070.7.224.1 to 70.7.239.25470.7.239.2554,094
12870.7.240.0/2070.7.240.1 to 70.7.255.25470.7.255.2554,094
12970.8.0.0/2070.8.0.1 to 70.8.15.25470.8.15.2554,094
13070.8.16.0/2070.8.16.1 to 70.8.31.25470.8.31.2554,094
13170.8.32.0/2070.8.32.1 to 70.8.47.25470.8.47.2554,094
13270.8.48.0/2070.8.48.1 to 70.8.63.25470.8.63.2554,094
13370.8.64.0/2070.8.64.1 to 70.8.79.25470.8.79.2554,094
13470.8.80.0/2070.8.80.1 to 70.8.95.25470.8.95.2554,094
13570.8.96.0/2070.8.96.1 to 70.8.111.25470.8.111.2554,094
13670.8.112.0/2070.8.112.1 to 70.8.127.25470.8.127.2554,094
13770.8.128.0/2070.8.128.1 to 70.8.143.25470.8.143.2554,094
13870.8.144.0/2070.8.144.1 to 70.8.159.25470.8.159.2554,094
13970.8.160.0/2070.8.160.1 to 70.8.175.25470.8.175.2554,094
14070.8.176.0/2070.8.176.1 to 70.8.191.25470.8.191.2554,094
14170.8.192.0/2070.8.192.1 to 70.8.207.25470.8.207.2554,094
14270.8.208.0/2070.8.208.1 to 70.8.223.25470.8.223.2554,094
14370.8.224.0/2070.8.224.1 to 70.8.239.25470.8.239.2554,094
14470.8.240.0/2070.8.240.1 to 70.8.255.25470.8.255.2554,094
14570.9.0.0/2070.9.0.1 to 70.9.15.25470.9.15.2554,094
14670.9.16.0/2070.9.16.1 to 70.9.31.25470.9.31.2554,094
14770.9.32.0/2070.9.32.1 to 70.9.47.25470.9.47.2554,094
14870.9.48.0/2070.9.48.1 to 70.9.63.25470.9.63.2554,094
14970.9.64.0/2070.9.64.1 to 70.9.79.25470.9.79.2554,094
15070.9.80.0/2070.9.80.1 to 70.9.95.25470.9.95.2554,094
15170.9.96.0/2070.9.96.1 to 70.9.111.25470.9.111.2554,094
15270.9.112.0/2070.9.112.1 to 70.9.127.25470.9.127.2554,094
15370.9.128.0/2070.9.128.1 to 70.9.143.25470.9.143.2554,094
15470.9.144.0/2070.9.144.1 to 70.9.159.25470.9.159.2554,094
15570.9.160.0/2070.9.160.1 to 70.9.175.25470.9.175.2554,094
15670.9.176.0/2070.9.176.1 to 70.9.191.25470.9.191.2554,094
15770.9.192.0/2070.9.192.1 to 70.9.207.25470.9.207.2554,094
15870.9.208.0/2070.9.208.1 to 70.9.223.25470.9.223.2554,094
15970.9.224.0/2070.9.224.1 to 70.9.239.25470.9.239.2554,094
16070.9.240.0/2070.9.240.1 to 70.9.255.25470.9.255.2554,094
16170.10.0.0/2070.10.0.1 to 70.10.15.25470.10.15.2554,094
16270.10.16.0/2070.10.16.1 to 70.10.31.25470.10.31.2554,094
16370.10.32.0/2070.10.32.1 to 70.10.47.25470.10.47.2554,094
16470.10.48.0/2070.10.48.1 to 70.10.63.25470.10.63.2554,094
16570.10.64.0/2070.10.64.1 to 70.10.79.25470.10.79.2554,094
16670.10.80.0/2070.10.80.1 to 70.10.95.25470.10.95.2554,094
16770.10.96.0/2070.10.96.1 to 70.10.111.25470.10.111.2554,094
16870.10.112.0/2070.10.112.1 to 70.10.127.25470.10.127.2554,094
16970.10.128.0/2070.10.128.1 to 70.10.143.25470.10.143.2554,094
17070.10.144.0/2070.10.144.1 to 70.10.159.25470.10.159.2554,094
17170.10.160.0/2070.10.160.1 to 70.10.175.25470.10.175.2554,094
17270.10.176.0/2070.10.176.1 to 70.10.191.25470.10.191.2554,094
17370.10.192.0/2070.10.192.1 to 70.10.207.25470.10.207.2554,094
17470.10.208.0/2070.10.208.1 to 70.10.223.25470.10.223.2554,094
17570.10.224.0/2070.10.224.1 to 70.10.239.25470.10.239.2554,094
17670.10.240.0/2070.10.240.1 to 70.10.255.25470.10.255.2554,094
17770.11.0.0/2070.11.0.1 to 70.11.15.25470.11.15.2554,094
17870.11.16.0/2070.11.16.1 to 70.11.31.25470.11.31.2554,094
17970.11.32.0/2070.11.32.1 to 70.11.47.25470.11.47.2554,094
18070.11.48.0/2070.11.48.1 to 70.11.63.25470.11.63.2554,094
18170.11.64.0/2070.11.64.1 to 70.11.79.25470.11.79.2554,094
18270.11.80.0/2070.11.80.1 to 70.11.95.25470.11.95.2554,094
18370.11.96.0/2070.11.96.1 to 70.11.111.25470.11.111.2554,094
18470.11.112.0/2070.11.112.1 to 70.11.127.25470.11.127.2554,094
18570.11.128.0/2070.11.128.1 to 70.11.143.25470.11.143.2554,094
18670.11.144.0/2070.11.144.1 to 70.11.159.25470.11.159.2554,094
18770.11.160.0/2070.11.160.1 to 70.11.175.25470.11.175.2554,094
18870.11.176.0/2070.11.176.1 to 70.11.191.25470.11.191.2554,094
18970.11.192.0/2070.11.192.1 to 70.11.207.25470.11.207.2554,094
19070.11.208.0/2070.11.208.1 to 70.11.223.25470.11.223.2554,094
19170.11.224.0/2070.11.224.1 to 70.11.239.25470.11.239.2554,094
19270.11.240.0/2070.11.240.1 to 70.11.255.25470.11.255.2554,094
19370.12.0.0/2070.12.0.1 to 70.12.15.25470.12.15.2554,094
19470.12.16.0/2070.12.16.1 to 70.12.31.25470.12.31.2554,094
19570.12.32.0/2070.12.32.1 to 70.12.47.25470.12.47.2554,094
19670.12.48.0/2070.12.48.1 to 70.12.63.25470.12.63.2554,094
19770.12.64.0/2070.12.64.1 to 70.12.79.25470.12.79.2554,094
19870.12.80.0/2070.12.80.1 to 70.12.95.25470.12.95.2554,094
19970.12.96.0/2070.12.96.1 to 70.12.111.25470.12.111.2554,094
20070.12.112.0/2070.12.112.1 to 70.12.127.25470.12.127.2554,094
20170.12.128.0/2070.12.128.1 to 70.12.143.25470.12.143.2554,094
20270.12.144.0/2070.12.144.1 to 70.12.159.25470.12.159.2554,094
20370.12.160.0/2070.12.160.1 to 70.12.175.25470.12.175.2554,094
20470.12.176.0/2070.12.176.1 to 70.12.191.25470.12.191.2554,094
20570.12.192.0/2070.12.192.1 to 70.12.207.25470.12.207.2554,094
20670.12.208.0/2070.12.208.1 to 70.12.223.25470.12.223.2554,094
20770.12.224.0/2070.12.224.1 to 70.12.239.25470.12.239.2554,094
20870.12.240.0/2070.12.240.1 to 70.12.255.25470.12.255.2554,094
20970.13.0.0/2070.13.0.1 to 70.13.15.25470.13.15.2554,094
21070.13.16.0/2070.13.16.1 to 70.13.31.25470.13.31.2554,094
21170.13.32.0/2070.13.32.1 to 70.13.47.25470.13.47.2554,094
21270.13.48.0/2070.13.48.1 to 70.13.63.25470.13.63.2554,094
21370.13.64.0/2070.13.64.1 to 70.13.79.25470.13.79.2554,094
21470.13.80.0/2070.13.80.1 to 70.13.95.25470.13.95.2554,094
21570.13.96.0/2070.13.96.1 to 70.13.111.25470.13.111.2554,094
21670.13.112.0/2070.13.112.1 to 70.13.127.25470.13.127.2554,094
21770.13.128.0/2070.13.128.1 to 70.13.143.25470.13.143.2554,094
21870.13.144.0/2070.13.144.1 to 70.13.159.25470.13.159.2554,094
21970.13.160.0/2070.13.160.1 to 70.13.175.25470.13.175.2554,094
22070.13.176.0/2070.13.176.1 to 70.13.191.25470.13.191.2554,094
22170.13.192.0/2070.13.192.1 to 70.13.207.25470.13.207.2554,094
22270.13.208.0/2070.13.208.1 to 70.13.223.25470.13.223.2554,094
22370.13.224.0/2070.13.224.1 to 70.13.239.25470.13.239.2554,094
22470.13.240.0/2070.13.240.1 to 70.13.255.25470.13.255.2554,094
22570.14.0.0/2070.14.0.1 to 70.14.15.25470.14.15.2554,094
22670.14.16.0/2070.14.16.1 to 70.14.31.25470.14.31.2554,094
22770.14.32.0/2070.14.32.1 to 70.14.47.25470.14.47.2554,094
22870.14.48.0/2070.14.48.1 to 70.14.63.25470.14.63.2554,094
22970.14.64.0/2070.14.64.1 to 70.14.79.25470.14.79.2554,094
23070.14.80.0/2070.14.80.1 to 70.14.95.25470.14.95.2554,094
23170.14.96.0/2070.14.96.1 to 70.14.111.25470.14.111.2554,094
23270.14.112.0/2070.14.112.1 to 70.14.127.25470.14.127.2554,094
23370.14.128.0/2070.14.128.1 to 70.14.143.25470.14.143.2554,094
23470.14.144.0/2070.14.144.1 to 70.14.159.25470.14.159.2554,094
23570.14.160.0/2070.14.160.1 to 70.14.175.25470.14.175.2554,094
23670.14.176.0/2070.14.176.1 to 70.14.191.25470.14.191.2554,094
23770.14.192.0/2070.14.192.1 to 70.14.207.25470.14.207.2554,094
23870.14.208.0/2070.14.208.1 to 70.14.223.25470.14.223.2554,094
23970.14.224.0/2070.14.224.1 to 70.14.239.25470.14.239.2554,094
24070.14.240.0/2070.14.240.1 to 70.14.255.25470.14.255.2554,094
24170.15.0.0/2070.15.0.1 to 70.15.15.25470.15.15.2554,094
24270.15.16.0/2070.15.16.1 to 70.15.31.25470.15.31.2554,094
24370.15.32.0/2070.15.32.1 to 70.15.47.25470.15.47.2554,094
24470.15.48.0/2070.15.48.1 to 70.15.63.25470.15.63.2554,094
24570.15.64.0/2070.15.64.1 to 70.15.79.25470.15.79.2554,094
24670.15.80.0/2070.15.80.1 to 70.15.95.25470.15.95.2554,094
24770.15.96.0/2070.15.96.1 to 70.15.111.25470.15.111.2554,094
24870.15.112.0/2070.15.112.1 to 70.15.127.25470.15.127.2554,094
24970.15.128.0/2070.15.128.1 to 70.15.143.25470.15.143.2554,094
25070.15.144.0/2070.15.144.1 to 70.15.159.25470.15.159.2554,094
25170.15.160.0/2070.15.160.1 to 70.15.175.25470.15.175.2554,094
25270.15.176.0/2070.15.176.1 to 70.15.191.25470.15.191.2554,094
25370.15.192.0/2070.15.192.1 to 70.15.207.25470.15.207.2554,094
25470.15.208.0/2070.15.208.1 to 70.15.223.25470.15.223.2554,094
25570.15.224.0/2070.15.224.1 to 70.15.239.25470.15.239.2554,094
25670.15.240.0/2070.15.240.1 to 70.15.255.25470.15.255.2554,094

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.