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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.

Network60.2.64.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
60.2.64.0
Broadcast address
60.2.95.255
First usable
60.2.64.1
Last usable
60.2.95.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C024000 · Integer 1006780416 to 1006788607
Reverse DNS zones
64.2.60.in-addr.arpa
65.2.60.in-addr.arpa
66.2.60.in-addr.arpa
67.2.60.in-addr.arpa
68.2.60.in-addr.arpa
69.2.60.in-addr.arpa
70.2.60.in-addr.arpa
71.2.60.in-addr.arpa
72.2.60.in-addr.arpa
73.2.60.in-addr.arpa
74.2.60.in-addr.arpa
75.2.60.in-addr.arpa
76.2.60.in-addr.arpa
77.2.60.in-addr.arpa
78.2.60.in-addr.arpa
79.2.60.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100.00000010.01000000.0000000060.2.64.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00111100.00000010.01000000.0000000060.2.64.0
Broadcast00111100.00000010.01011111.1111111160.2.95.255
Split into smaller subnets/30
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

60.2.64.0/19 makes 2,048 subnets of /30; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.2.64.0/3060.2.64.1 to 60.2.64.260.2.64.32
260.2.64.4/3060.2.64.5 to 60.2.64.660.2.64.72
360.2.64.8/3060.2.64.9 to 60.2.64.1060.2.64.112
460.2.64.12/3060.2.64.13 to 60.2.64.1460.2.64.152
560.2.64.16/3060.2.64.17 to 60.2.64.1860.2.64.192
660.2.64.20/3060.2.64.21 to 60.2.64.2260.2.64.232
760.2.64.24/3060.2.64.25 to 60.2.64.2660.2.64.272
860.2.64.28/3060.2.64.29 to 60.2.64.3060.2.64.312
960.2.64.32/3060.2.64.33 to 60.2.64.3460.2.64.352
1060.2.64.36/3060.2.64.37 to 60.2.64.3860.2.64.392
1160.2.64.40/3060.2.64.41 to 60.2.64.4260.2.64.432
1260.2.64.44/3060.2.64.45 to 60.2.64.4660.2.64.472
1360.2.64.48/3060.2.64.49 to 60.2.64.5060.2.64.512
1460.2.64.52/3060.2.64.53 to 60.2.64.5460.2.64.552
1560.2.64.56/3060.2.64.57 to 60.2.64.5860.2.64.592
1660.2.64.60/3060.2.64.61 to 60.2.64.6260.2.64.632
1760.2.64.64/3060.2.64.65 to 60.2.64.6660.2.64.672
1860.2.64.68/3060.2.64.69 to 60.2.64.7060.2.64.712
1960.2.64.72/3060.2.64.73 to 60.2.64.7460.2.64.752
2060.2.64.76/3060.2.64.77 to 60.2.64.7860.2.64.792
2160.2.64.80/3060.2.64.81 to 60.2.64.8260.2.64.832
2260.2.64.84/3060.2.64.85 to 60.2.64.8660.2.64.872
2360.2.64.88/3060.2.64.89 to 60.2.64.9060.2.64.912
2460.2.64.92/3060.2.64.93 to 60.2.64.9460.2.64.952
2560.2.64.96/3060.2.64.97 to 60.2.64.9860.2.64.992
2660.2.64.100/3060.2.64.101 to 60.2.64.10260.2.64.1032
2760.2.64.104/3060.2.64.105 to 60.2.64.10660.2.64.1072
2860.2.64.108/3060.2.64.109 to 60.2.64.11060.2.64.1112
2960.2.64.112/3060.2.64.113 to 60.2.64.11460.2.64.1152
3060.2.64.116/3060.2.64.117 to 60.2.64.11860.2.64.1192
3160.2.64.120/3060.2.64.121 to 60.2.64.12260.2.64.1232
3260.2.64.124/3060.2.64.125 to 60.2.64.12660.2.64.1272
3360.2.64.128/3060.2.64.129 to 60.2.64.13060.2.64.1312
3460.2.64.132/3060.2.64.133 to 60.2.64.13460.2.64.1352
3560.2.64.136/3060.2.64.137 to 60.2.64.13860.2.64.1392
3660.2.64.140/3060.2.64.141 to 60.2.64.14260.2.64.1432
3760.2.64.144/3060.2.64.145 to 60.2.64.14660.2.64.1472
3860.2.64.148/3060.2.64.149 to 60.2.64.15060.2.64.1512
3960.2.64.152/3060.2.64.153 to 60.2.64.15460.2.64.1552
4060.2.64.156/3060.2.64.157 to 60.2.64.15860.2.64.1592
4160.2.64.160/3060.2.64.161 to 60.2.64.16260.2.64.1632
4260.2.64.164/3060.2.64.165 to 60.2.64.16660.2.64.1672
4360.2.64.168/3060.2.64.169 to 60.2.64.17060.2.64.1712
4460.2.64.172/3060.2.64.173 to 60.2.64.17460.2.64.1752
4560.2.64.176/3060.2.64.177 to 60.2.64.17860.2.64.1792
4660.2.64.180/3060.2.64.181 to 60.2.64.18260.2.64.1832
4760.2.64.184/3060.2.64.185 to 60.2.64.18660.2.64.1872
4860.2.64.188/3060.2.64.189 to 60.2.64.19060.2.64.1912
4960.2.64.192/3060.2.64.193 to 60.2.64.19460.2.64.1952
5060.2.64.196/3060.2.64.197 to 60.2.64.19860.2.64.1992
5160.2.64.200/3060.2.64.201 to 60.2.64.20260.2.64.2032
5260.2.64.204/3060.2.64.205 to 60.2.64.20660.2.64.2072
5360.2.64.208/3060.2.64.209 to 60.2.64.21060.2.64.2112
5460.2.64.212/3060.2.64.213 to 60.2.64.21460.2.64.2152
5560.2.64.216/3060.2.64.217 to 60.2.64.21860.2.64.2192
5660.2.64.220/3060.2.64.221 to 60.2.64.22260.2.64.2232
5760.2.64.224/3060.2.64.225 to 60.2.64.22660.2.64.2272
5860.2.64.228/3060.2.64.229 to 60.2.64.23060.2.64.2312
5960.2.64.232/3060.2.64.233 to 60.2.64.23460.2.64.2352
6060.2.64.236/3060.2.64.237 to 60.2.64.23860.2.64.2392
6160.2.64.240/3060.2.64.241 to 60.2.64.24260.2.64.2432
6260.2.64.244/3060.2.64.245 to 60.2.64.24660.2.64.2472
6360.2.64.248/3060.2.64.249 to 60.2.64.25060.2.64.2512
6460.2.64.252/3060.2.64.253 to 60.2.64.25460.2.64.2552
6560.2.65.0/3060.2.65.1 to 60.2.65.260.2.65.32
6660.2.65.4/3060.2.65.5 to 60.2.65.660.2.65.72
6760.2.65.8/3060.2.65.9 to 60.2.65.1060.2.65.112
6860.2.65.12/3060.2.65.13 to 60.2.65.1460.2.65.152
6960.2.65.16/3060.2.65.17 to 60.2.65.1860.2.65.192
7060.2.65.20/3060.2.65.21 to 60.2.65.2260.2.65.232
7160.2.65.24/3060.2.65.25 to 60.2.65.2660.2.65.272
7260.2.65.28/3060.2.65.29 to 60.2.65.3060.2.65.312
7360.2.65.32/3060.2.65.33 to 60.2.65.3460.2.65.352
7460.2.65.36/3060.2.65.37 to 60.2.65.3860.2.65.392
7560.2.65.40/3060.2.65.41 to 60.2.65.4260.2.65.432
7660.2.65.44/3060.2.65.45 to 60.2.65.4660.2.65.472
7760.2.65.48/3060.2.65.49 to 60.2.65.5060.2.65.512
7860.2.65.52/3060.2.65.53 to 60.2.65.5460.2.65.552
7960.2.65.56/3060.2.65.57 to 60.2.65.5860.2.65.592
8060.2.65.60/3060.2.65.61 to 60.2.65.6260.2.65.632
8160.2.65.64/3060.2.65.65 to 60.2.65.6660.2.65.672
8260.2.65.68/3060.2.65.69 to 60.2.65.7060.2.65.712
8360.2.65.72/3060.2.65.73 to 60.2.65.7460.2.65.752
8460.2.65.76/3060.2.65.77 to 60.2.65.7860.2.65.792
8560.2.65.80/3060.2.65.81 to 60.2.65.8260.2.65.832
8660.2.65.84/3060.2.65.85 to 60.2.65.8660.2.65.872
8760.2.65.88/3060.2.65.89 to 60.2.65.9060.2.65.912
8860.2.65.92/3060.2.65.93 to 60.2.65.9460.2.65.952
8960.2.65.96/3060.2.65.97 to 60.2.65.9860.2.65.992
9060.2.65.100/3060.2.65.101 to 60.2.65.10260.2.65.1032
9160.2.65.104/3060.2.65.105 to 60.2.65.10660.2.65.1072
9260.2.65.108/3060.2.65.109 to 60.2.65.11060.2.65.1112
9360.2.65.112/3060.2.65.113 to 60.2.65.11460.2.65.1152
9460.2.65.116/3060.2.65.117 to 60.2.65.11860.2.65.1192
9560.2.65.120/3060.2.65.121 to 60.2.65.12260.2.65.1232
9660.2.65.124/3060.2.65.125 to 60.2.65.12660.2.65.1272
9760.2.65.128/3060.2.65.129 to 60.2.65.13060.2.65.1312
9860.2.65.132/3060.2.65.133 to 60.2.65.13460.2.65.1352
9960.2.65.136/3060.2.65.137 to 60.2.65.13860.2.65.1392
10060.2.65.140/3060.2.65.141 to 60.2.65.14260.2.65.1432
10160.2.65.144/3060.2.65.145 to 60.2.65.14660.2.65.1472
10260.2.65.148/3060.2.65.149 to 60.2.65.15060.2.65.1512
10360.2.65.152/3060.2.65.153 to 60.2.65.15460.2.65.1552
10460.2.65.156/3060.2.65.157 to 60.2.65.15860.2.65.1592
10560.2.65.160/3060.2.65.161 to 60.2.65.16260.2.65.1632
10660.2.65.164/3060.2.65.165 to 60.2.65.16660.2.65.1672
10760.2.65.168/3060.2.65.169 to 60.2.65.17060.2.65.1712
10860.2.65.172/3060.2.65.173 to 60.2.65.17460.2.65.1752
10960.2.65.176/3060.2.65.177 to 60.2.65.17860.2.65.1792
11060.2.65.180/3060.2.65.181 to 60.2.65.18260.2.65.1832
11160.2.65.184/3060.2.65.185 to 60.2.65.18660.2.65.1872
11260.2.65.188/3060.2.65.189 to 60.2.65.19060.2.65.1912
11360.2.65.192/3060.2.65.193 to 60.2.65.19460.2.65.1952
11460.2.65.196/3060.2.65.197 to 60.2.65.19860.2.65.1992
11560.2.65.200/3060.2.65.201 to 60.2.65.20260.2.65.2032
11660.2.65.204/3060.2.65.205 to 60.2.65.20660.2.65.2072
11760.2.65.208/3060.2.65.209 to 60.2.65.21060.2.65.2112
11860.2.65.212/3060.2.65.213 to 60.2.65.21460.2.65.2152
11960.2.65.216/3060.2.65.217 to 60.2.65.21860.2.65.2192
12060.2.65.220/3060.2.65.221 to 60.2.65.22260.2.65.2232
12160.2.65.224/3060.2.65.225 to 60.2.65.22660.2.65.2272
12260.2.65.228/3060.2.65.229 to 60.2.65.23060.2.65.2312
12360.2.65.232/3060.2.65.233 to 60.2.65.23460.2.65.2352
12460.2.65.236/3060.2.65.237 to 60.2.65.23860.2.65.2392
12560.2.65.240/3060.2.65.241 to 60.2.65.24260.2.65.2432
12660.2.65.244/3060.2.65.245 to 60.2.65.24660.2.65.2472
12760.2.65.248/3060.2.65.249 to 60.2.65.25060.2.65.2512
12860.2.65.252/3060.2.65.253 to 60.2.65.25460.2.65.2552
12960.2.66.0/3060.2.66.1 to 60.2.66.260.2.66.32
13060.2.66.4/3060.2.66.5 to 60.2.66.660.2.66.72
13160.2.66.8/3060.2.66.9 to 60.2.66.1060.2.66.112
13260.2.66.12/3060.2.66.13 to 60.2.66.1460.2.66.152
13360.2.66.16/3060.2.66.17 to 60.2.66.1860.2.66.192
13460.2.66.20/3060.2.66.21 to 60.2.66.2260.2.66.232
13560.2.66.24/3060.2.66.25 to 60.2.66.2660.2.66.272
13660.2.66.28/3060.2.66.29 to 60.2.66.3060.2.66.312
13760.2.66.32/3060.2.66.33 to 60.2.66.3460.2.66.352
13860.2.66.36/3060.2.66.37 to 60.2.66.3860.2.66.392
13960.2.66.40/3060.2.66.41 to 60.2.66.4260.2.66.432
14060.2.66.44/3060.2.66.45 to 60.2.66.4660.2.66.472
14160.2.66.48/3060.2.66.49 to 60.2.66.5060.2.66.512
14260.2.66.52/3060.2.66.53 to 60.2.66.5460.2.66.552
14360.2.66.56/3060.2.66.57 to 60.2.66.5860.2.66.592
14460.2.66.60/3060.2.66.61 to 60.2.66.6260.2.66.632
14560.2.66.64/3060.2.66.65 to 60.2.66.6660.2.66.672
14660.2.66.68/3060.2.66.69 to 60.2.66.7060.2.66.712
14760.2.66.72/3060.2.66.73 to 60.2.66.7460.2.66.752
14860.2.66.76/3060.2.66.77 to 60.2.66.7860.2.66.792
14960.2.66.80/3060.2.66.81 to 60.2.66.8260.2.66.832
15060.2.66.84/3060.2.66.85 to 60.2.66.8660.2.66.872
15160.2.66.88/3060.2.66.89 to 60.2.66.9060.2.66.912
15260.2.66.92/3060.2.66.93 to 60.2.66.9460.2.66.952
15360.2.66.96/3060.2.66.97 to 60.2.66.9860.2.66.992
15460.2.66.100/3060.2.66.101 to 60.2.66.10260.2.66.1032
15560.2.66.104/3060.2.66.105 to 60.2.66.10660.2.66.1072
15660.2.66.108/3060.2.66.109 to 60.2.66.11060.2.66.1112
15760.2.66.112/3060.2.66.113 to 60.2.66.11460.2.66.1152
15860.2.66.116/3060.2.66.117 to 60.2.66.11860.2.66.1192
15960.2.66.120/3060.2.66.121 to 60.2.66.12260.2.66.1232
16060.2.66.124/3060.2.66.125 to 60.2.66.12660.2.66.1272
16160.2.66.128/3060.2.66.129 to 60.2.66.13060.2.66.1312
16260.2.66.132/3060.2.66.133 to 60.2.66.13460.2.66.1352
16360.2.66.136/3060.2.66.137 to 60.2.66.13860.2.66.1392
16460.2.66.140/3060.2.66.141 to 60.2.66.14260.2.66.1432
16560.2.66.144/3060.2.66.145 to 60.2.66.14660.2.66.1472
16660.2.66.148/3060.2.66.149 to 60.2.66.15060.2.66.1512
16760.2.66.152/3060.2.66.153 to 60.2.66.15460.2.66.1552
16860.2.66.156/3060.2.66.157 to 60.2.66.15860.2.66.1592
16960.2.66.160/3060.2.66.161 to 60.2.66.16260.2.66.1632
17060.2.66.164/3060.2.66.165 to 60.2.66.16660.2.66.1672
17160.2.66.168/3060.2.66.169 to 60.2.66.17060.2.66.1712
17260.2.66.172/3060.2.66.173 to 60.2.66.17460.2.66.1752
17360.2.66.176/3060.2.66.177 to 60.2.66.17860.2.66.1792
17460.2.66.180/3060.2.66.181 to 60.2.66.18260.2.66.1832
17560.2.66.184/3060.2.66.185 to 60.2.66.18660.2.66.1872
17660.2.66.188/3060.2.66.189 to 60.2.66.19060.2.66.1912
17760.2.66.192/3060.2.66.193 to 60.2.66.19460.2.66.1952
17860.2.66.196/3060.2.66.197 to 60.2.66.19860.2.66.1992
17960.2.66.200/3060.2.66.201 to 60.2.66.20260.2.66.2032
18060.2.66.204/3060.2.66.205 to 60.2.66.20660.2.66.2072
18160.2.66.208/3060.2.66.209 to 60.2.66.21060.2.66.2112
18260.2.66.212/3060.2.66.213 to 60.2.66.21460.2.66.2152
18360.2.66.216/3060.2.66.217 to 60.2.66.21860.2.66.2192
18460.2.66.220/3060.2.66.221 to 60.2.66.22260.2.66.2232
18560.2.66.224/3060.2.66.225 to 60.2.66.22660.2.66.2272
18660.2.66.228/3060.2.66.229 to 60.2.66.23060.2.66.2312
18760.2.66.232/3060.2.66.233 to 60.2.66.23460.2.66.2352
18860.2.66.236/3060.2.66.237 to 60.2.66.23860.2.66.2392
18960.2.66.240/3060.2.66.241 to 60.2.66.24260.2.66.2432
19060.2.66.244/3060.2.66.245 to 60.2.66.24660.2.66.2472
19160.2.66.248/3060.2.66.249 to 60.2.66.25060.2.66.2512
19260.2.66.252/3060.2.66.253 to 60.2.66.25460.2.66.2552
19360.2.67.0/3060.2.67.1 to 60.2.67.260.2.67.32
19460.2.67.4/3060.2.67.5 to 60.2.67.660.2.67.72
19560.2.67.8/3060.2.67.9 to 60.2.67.1060.2.67.112
19660.2.67.12/3060.2.67.13 to 60.2.67.1460.2.67.152
19760.2.67.16/3060.2.67.17 to 60.2.67.1860.2.67.192
19860.2.67.20/3060.2.67.21 to 60.2.67.2260.2.67.232
19960.2.67.24/3060.2.67.25 to 60.2.67.2660.2.67.272
20060.2.67.28/3060.2.67.29 to 60.2.67.3060.2.67.312
20160.2.67.32/3060.2.67.33 to 60.2.67.3460.2.67.352
20260.2.67.36/3060.2.67.37 to 60.2.67.3860.2.67.392
20360.2.67.40/3060.2.67.41 to 60.2.67.4260.2.67.432
20460.2.67.44/3060.2.67.45 to 60.2.67.4660.2.67.472
20560.2.67.48/3060.2.67.49 to 60.2.67.5060.2.67.512
20660.2.67.52/3060.2.67.53 to 60.2.67.5460.2.67.552
20760.2.67.56/3060.2.67.57 to 60.2.67.5860.2.67.592
20860.2.67.60/3060.2.67.61 to 60.2.67.6260.2.67.632
20960.2.67.64/3060.2.67.65 to 60.2.67.6660.2.67.672
21060.2.67.68/3060.2.67.69 to 60.2.67.7060.2.67.712
21160.2.67.72/3060.2.67.73 to 60.2.67.7460.2.67.752
21260.2.67.76/3060.2.67.77 to 60.2.67.7860.2.67.792
21360.2.67.80/3060.2.67.81 to 60.2.67.8260.2.67.832
21460.2.67.84/3060.2.67.85 to 60.2.67.8660.2.67.872
21560.2.67.88/3060.2.67.89 to 60.2.67.9060.2.67.912
21660.2.67.92/3060.2.67.93 to 60.2.67.9460.2.67.952
21760.2.67.96/3060.2.67.97 to 60.2.67.9860.2.67.992
21860.2.67.100/3060.2.67.101 to 60.2.67.10260.2.67.1032
21960.2.67.104/3060.2.67.105 to 60.2.67.10660.2.67.1072
22060.2.67.108/3060.2.67.109 to 60.2.67.11060.2.67.1112
22160.2.67.112/3060.2.67.113 to 60.2.67.11460.2.67.1152
22260.2.67.116/3060.2.67.117 to 60.2.67.11860.2.67.1192
22360.2.67.120/3060.2.67.121 to 60.2.67.12260.2.67.1232
22460.2.67.124/3060.2.67.125 to 60.2.67.12660.2.67.1272
22560.2.67.128/3060.2.67.129 to 60.2.67.13060.2.67.1312
22660.2.67.132/3060.2.67.133 to 60.2.67.13460.2.67.1352
22760.2.67.136/3060.2.67.137 to 60.2.67.13860.2.67.1392
22860.2.67.140/3060.2.67.141 to 60.2.67.14260.2.67.1432
22960.2.67.144/3060.2.67.145 to 60.2.67.14660.2.67.1472
23060.2.67.148/3060.2.67.149 to 60.2.67.15060.2.67.1512
23160.2.67.152/3060.2.67.153 to 60.2.67.15460.2.67.1552
23260.2.67.156/3060.2.67.157 to 60.2.67.15860.2.67.1592
23360.2.67.160/3060.2.67.161 to 60.2.67.16260.2.67.1632
23460.2.67.164/3060.2.67.165 to 60.2.67.16660.2.67.1672
23560.2.67.168/3060.2.67.169 to 60.2.67.17060.2.67.1712
23660.2.67.172/3060.2.67.173 to 60.2.67.17460.2.67.1752
23760.2.67.176/3060.2.67.177 to 60.2.67.17860.2.67.1792
23860.2.67.180/3060.2.67.181 to 60.2.67.18260.2.67.1832
23960.2.67.184/3060.2.67.185 to 60.2.67.18660.2.67.1872
24060.2.67.188/3060.2.67.189 to 60.2.67.19060.2.67.1912
24160.2.67.192/3060.2.67.193 to 60.2.67.19460.2.67.1952
24260.2.67.196/3060.2.67.197 to 60.2.67.19860.2.67.1992
24360.2.67.200/3060.2.67.201 to 60.2.67.20260.2.67.2032
24460.2.67.204/3060.2.67.205 to 60.2.67.20660.2.67.2072
24560.2.67.208/3060.2.67.209 to 60.2.67.21060.2.67.2112
24660.2.67.212/3060.2.67.213 to 60.2.67.21460.2.67.2152
24760.2.67.216/3060.2.67.217 to 60.2.67.21860.2.67.2192
24860.2.67.220/3060.2.67.221 to 60.2.67.22260.2.67.2232
24960.2.67.224/3060.2.67.225 to 60.2.67.22660.2.67.2272
25060.2.67.228/3060.2.67.229 to 60.2.67.23060.2.67.2312
25160.2.67.232/3060.2.67.233 to 60.2.67.23460.2.67.2352
25260.2.67.236/3060.2.67.237 to 60.2.67.23860.2.67.2392
25360.2.67.240/3060.2.67.241 to 60.2.67.24260.2.67.2432
25460.2.67.244/3060.2.67.245 to 60.2.67.24660.2.67.2472
25560.2.67.248/3060.2.67.249 to 60.2.67.25060.2.67.2512
25660.2.67.252/3060.2.67.253 to 60.2.67.25460.2.67.2552

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.