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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.

Network85.2.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
85.2.0.0
Broadcast address
85.2.63.255
First usable
85.2.0.1
Last usable
85.2.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 55020000 · Integer 1426194432 to 1426210815
Reverse DNS zones
0.2.85.in-addr.arpa
1.2.85.in-addr.arpa
2.2.85.in-addr.arpa
3.2.85.in-addr.arpa
4.2.85.in-addr.arpa
5.2.85.in-addr.arpa
6.2.85.in-addr.arpa
7.2.85.in-addr.arpa
8.2.85.in-addr.arpa
9.2.85.in-addr.arpa
10.2.85.in-addr.arpa
11.2.85.in-addr.arpa
12.2.85.in-addr.arpa
13.2.85.in-addr.arpa
14.2.85.in-addr.arpa
15.2.85.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010101.00000010.00000000.0000000085.2.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01010101.00000010.00000000.0000000085.2.0.0
Broadcast01010101.00000010.00111111.1111111185.2.63.255
Split into smaller subnets/29

85.2.0.0/18 makes 2,048 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
185.2.0.0/2985.2.0.1 to 85.2.0.685.2.0.76
285.2.0.8/2985.2.0.9 to 85.2.0.1485.2.0.156
385.2.0.16/2985.2.0.17 to 85.2.0.2285.2.0.236
485.2.0.24/2985.2.0.25 to 85.2.0.3085.2.0.316
585.2.0.32/2985.2.0.33 to 85.2.0.3885.2.0.396
685.2.0.40/2985.2.0.41 to 85.2.0.4685.2.0.476
785.2.0.48/2985.2.0.49 to 85.2.0.5485.2.0.556
885.2.0.56/2985.2.0.57 to 85.2.0.6285.2.0.636
985.2.0.64/2985.2.0.65 to 85.2.0.7085.2.0.716
1085.2.0.72/2985.2.0.73 to 85.2.0.7885.2.0.796
1185.2.0.80/2985.2.0.81 to 85.2.0.8685.2.0.876
1285.2.0.88/2985.2.0.89 to 85.2.0.9485.2.0.956
1385.2.0.96/2985.2.0.97 to 85.2.0.10285.2.0.1036
1485.2.0.104/2985.2.0.105 to 85.2.0.11085.2.0.1116
1585.2.0.112/2985.2.0.113 to 85.2.0.11885.2.0.1196
1685.2.0.120/2985.2.0.121 to 85.2.0.12685.2.0.1276
1785.2.0.128/2985.2.0.129 to 85.2.0.13485.2.0.1356
1885.2.0.136/2985.2.0.137 to 85.2.0.14285.2.0.1436
1985.2.0.144/2985.2.0.145 to 85.2.0.15085.2.0.1516
2085.2.0.152/2985.2.0.153 to 85.2.0.15885.2.0.1596
2185.2.0.160/2985.2.0.161 to 85.2.0.16685.2.0.1676
2285.2.0.168/2985.2.0.169 to 85.2.0.17485.2.0.1756
2385.2.0.176/2985.2.0.177 to 85.2.0.18285.2.0.1836
2485.2.0.184/2985.2.0.185 to 85.2.0.19085.2.0.1916
2585.2.0.192/2985.2.0.193 to 85.2.0.19885.2.0.1996
2685.2.0.200/2985.2.0.201 to 85.2.0.20685.2.0.2076
2785.2.0.208/2985.2.0.209 to 85.2.0.21485.2.0.2156
2885.2.0.216/2985.2.0.217 to 85.2.0.22285.2.0.2236
2985.2.0.224/2985.2.0.225 to 85.2.0.23085.2.0.2316
3085.2.0.232/2985.2.0.233 to 85.2.0.23885.2.0.2396
3185.2.0.240/2985.2.0.241 to 85.2.0.24685.2.0.2476
3285.2.0.248/2985.2.0.249 to 85.2.0.25485.2.0.2556
3385.2.1.0/2985.2.1.1 to 85.2.1.685.2.1.76
3485.2.1.8/2985.2.1.9 to 85.2.1.1485.2.1.156
3585.2.1.16/2985.2.1.17 to 85.2.1.2285.2.1.236
3685.2.1.24/2985.2.1.25 to 85.2.1.3085.2.1.316
3785.2.1.32/2985.2.1.33 to 85.2.1.3885.2.1.396
3885.2.1.40/2985.2.1.41 to 85.2.1.4685.2.1.476
3985.2.1.48/2985.2.1.49 to 85.2.1.5485.2.1.556
4085.2.1.56/2985.2.1.57 to 85.2.1.6285.2.1.636
4185.2.1.64/2985.2.1.65 to 85.2.1.7085.2.1.716
4285.2.1.72/2985.2.1.73 to 85.2.1.7885.2.1.796
4385.2.1.80/2985.2.1.81 to 85.2.1.8685.2.1.876
4485.2.1.88/2985.2.1.89 to 85.2.1.9485.2.1.956
4585.2.1.96/2985.2.1.97 to 85.2.1.10285.2.1.1036
4685.2.1.104/2985.2.1.105 to 85.2.1.11085.2.1.1116
4785.2.1.112/2985.2.1.113 to 85.2.1.11885.2.1.1196
4885.2.1.120/2985.2.1.121 to 85.2.1.12685.2.1.1276
4985.2.1.128/2985.2.1.129 to 85.2.1.13485.2.1.1356
5085.2.1.136/2985.2.1.137 to 85.2.1.14285.2.1.1436
5185.2.1.144/2985.2.1.145 to 85.2.1.15085.2.1.1516
5285.2.1.152/2985.2.1.153 to 85.2.1.15885.2.1.1596
5385.2.1.160/2985.2.1.161 to 85.2.1.16685.2.1.1676
5485.2.1.168/2985.2.1.169 to 85.2.1.17485.2.1.1756
5585.2.1.176/2985.2.1.177 to 85.2.1.18285.2.1.1836
5685.2.1.184/2985.2.1.185 to 85.2.1.19085.2.1.1916
5785.2.1.192/2985.2.1.193 to 85.2.1.19885.2.1.1996
5885.2.1.200/2985.2.1.201 to 85.2.1.20685.2.1.2076
5985.2.1.208/2985.2.1.209 to 85.2.1.21485.2.1.2156
6085.2.1.216/2985.2.1.217 to 85.2.1.22285.2.1.2236
6185.2.1.224/2985.2.1.225 to 85.2.1.23085.2.1.2316
6285.2.1.232/2985.2.1.233 to 85.2.1.23885.2.1.2396
6385.2.1.240/2985.2.1.241 to 85.2.1.24685.2.1.2476
6485.2.1.248/2985.2.1.249 to 85.2.1.25485.2.1.2556
6585.2.2.0/2985.2.2.1 to 85.2.2.685.2.2.76
6685.2.2.8/2985.2.2.9 to 85.2.2.1485.2.2.156
6785.2.2.16/2985.2.2.17 to 85.2.2.2285.2.2.236
6885.2.2.24/2985.2.2.25 to 85.2.2.3085.2.2.316
6985.2.2.32/2985.2.2.33 to 85.2.2.3885.2.2.396
7085.2.2.40/2985.2.2.41 to 85.2.2.4685.2.2.476
7185.2.2.48/2985.2.2.49 to 85.2.2.5485.2.2.556
7285.2.2.56/2985.2.2.57 to 85.2.2.6285.2.2.636
7385.2.2.64/2985.2.2.65 to 85.2.2.7085.2.2.716
7485.2.2.72/2985.2.2.73 to 85.2.2.7885.2.2.796
7585.2.2.80/2985.2.2.81 to 85.2.2.8685.2.2.876
7685.2.2.88/2985.2.2.89 to 85.2.2.9485.2.2.956
7785.2.2.96/2985.2.2.97 to 85.2.2.10285.2.2.1036
7885.2.2.104/2985.2.2.105 to 85.2.2.11085.2.2.1116
7985.2.2.112/2985.2.2.113 to 85.2.2.11885.2.2.1196
8085.2.2.120/2985.2.2.121 to 85.2.2.12685.2.2.1276
8185.2.2.128/2985.2.2.129 to 85.2.2.13485.2.2.1356
8285.2.2.136/2985.2.2.137 to 85.2.2.14285.2.2.1436
8385.2.2.144/2985.2.2.145 to 85.2.2.15085.2.2.1516
8485.2.2.152/2985.2.2.153 to 85.2.2.15885.2.2.1596
8585.2.2.160/2985.2.2.161 to 85.2.2.16685.2.2.1676
8685.2.2.168/2985.2.2.169 to 85.2.2.17485.2.2.1756
8785.2.2.176/2985.2.2.177 to 85.2.2.18285.2.2.1836
8885.2.2.184/2985.2.2.185 to 85.2.2.19085.2.2.1916
8985.2.2.192/2985.2.2.193 to 85.2.2.19885.2.2.1996
9085.2.2.200/2985.2.2.201 to 85.2.2.20685.2.2.2076
9185.2.2.208/2985.2.2.209 to 85.2.2.21485.2.2.2156
9285.2.2.216/2985.2.2.217 to 85.2.2.22285.2.2.2236
9385.2.2.224/2985.2.2.225 to 85.2.2.23085.2.2.2316
9485.2.2.232/2985.2.2.233 to 85.2.2.23885.2.2.2396
9585.2.2.240/2985.2.2.241 to 85.2.2.24685.2.2.2476
9685.2.2.248/2985.2.2.249 to 85.2.2.25485.2.2.2556
9785.2.3.0/2985.2.3.1 to 85.2.3.685.2.3.76
9885.2.3.8/2985.2.3.9 to 85.2.3.1485.2.3.156
9985.2.3.16/2985.2.3.17 to 85.2.3.2285.2.3.236
10085.2.3.24/2985.2.3.25 to 85.2.3.3085.2.3.316
10185.2.3.32/2985.2.3.33 to 85.2.3.3885.2.3.396
10285.2.3.40/2985.2.3.41 to 85.2.3.4685.2.3.476
10385.2.3.48/2985.2.3.49 to 85.2.3.5485.2.3.556
10485.2.3.56/2985.2.3.57 to 85.2.3.6285.2.3.636
10585.2.3.64/2985.2.3.65 to 85.2.3.7085.2.3.716
10685.2.3.72/2985.2.3.73 to 85.2.3.7885.2.3.796
10785.2.3.80/2985.2.3.81 to 85.2.3.8685.2.3.876
10885.2.3.88/2985.2.3.89 to 85.2.3.9485.2.3.956
10985.2.3.96/2985.2.3.97 to 85.2.3.10285.2.3.1036
11085.2.3.104/2985.2.3.105 to 85.2.3.11085.2.3.1116
11185.2.3.112/2985.2.3.113 to 85.2.3.11885.2.3.1196
11285.2.3.120/2985.2.3.121 to 85.2.3.12685.2.3.1276
11385.2.3.128/2985.2.3.129 to 85.2.3.13485.2.3.1356
11485.2.3.136/2985.2.3.137 to 85.2.3.14285.2.3.1436
11585.2.3.144/2985.2.3.145 to 85.2.3.15085.2.3.1516
11685.2.3.152/2985.2.3.153 to 85.2.3.15885.2.3.1596
11785.2.3.160/2985.2.3.161 to 85.2.3.16685.2.3.1676
11885.2.3.168/2985.2.3.169 to 85.2.3.17485.2.3.1756
11985.2.3.176/2985.2.3.177 to 85.2.3.18285.2.3.1836
12085.2.3.184/2985.2.3.185 to 85.2.3.19085.2.3.1916
12185.2.3.192/2985.2.3.193 to 85.2.3.19885.2.3.1996
12285.2.3.200/2985.2.3.201 to 85.2.3.20685.2.3.2076
12385.2.3.208/2985.2.3.209 to 85.2.3.21485.2.3.2156
12485.2.3.216/2985.2.3.217 to 85.2.3.22285.2.3.2236
12585.2.3.224/2985.2.3.225 to 85.2.3.23085.2.3.2316
12685.2.3.232/2985.2.3.233 to 85.2.3.23885.2.3.2396
12785.2.3.240/2985.2.3.241 to 85.2.3.24685.2.3.2476
12885.2.3.248/2985.2.3.249 to 85.2.3.25485.2.3.2556
12985.2.4.0/2985.2.4.1 to 85.2.4.685.2.4.76
13085.2.4.8/2985.2.4.9 to 85.2.4.1485.2.4.156
13185.2.4.16/2985.2.4.17 to 85.2.4.2285.2.4.236
13285.2.4.24/2985.2.4.25 to 85.2.4.3085.2.4.316
13385.2.4.32/2985.2.4.33 to 85.2.4.3885.2.4.396
13485.2.4.40/2985.2.4.41 to 85.2.4.4685.2.4.476
13585.2.4.48/2985.2.4.49 to 85.2.4.5485.2.4.556
13685.2.4.56/2985.2.4.57 to 85.2.4.6285.2.4.636
13785.2.4.64/2985.2.4.65 to 85.2.4.7085.2.4.716
13885.2.4.72/2985.2.4.73 to 85.2.4.7885.2.4.796
13985.2.4.80/2985.2.4.81 to 85.2.4.8685.2.4.876
14085.2.4.88/2985.2.4.89 to 85.2.4.9485.2.4.956
14185.2.4.96/2985.2.4.97 to 85.2.4.10285.2.4.1036
14285.2.4.104/2985.2.4.105 to 85.2.4.11085.2.4.1116
14385.2.4.112/2985.2.4.113 to 85.2.4.11885.2.4.1196
14485.2.4.120/2985.2.4.121 to 85.2.4.12685.2.4.1276
14585.2.4.128/2985.2.4.129 to 85.2.4.13485.2.4.1356
14685.2.4.136/2985.2.4.137 to 85.2.4.14285.2.4.1436
14785.2.4.144/2985.2.4.145 to 85.2.4.15085.2.4.1516
14885.2.4.152/2985.2.4.153 to 85.2.4.15885.2.4.1596
14985.2.4.160/2985.2.4.161 to 85.2.4.16685.2.4.1676
15085.2.4.168/2985.2.4.169 to 85.2.4.17485.2.4.1756
15185.2.4.176/2985.2.4.177 to 85.2.4.18285.2.4.1836
15285.2.4.184/2985.2.4.185 to 85.2.4.19085.2.4.1916
15385.2.4.192/2985.2.4.193 to 85.2.4.19885.2.4.1996
15485.2.4.200/2985.2.4.201 to 85.2.4.20685.2.4.2076
15585.2.4.208/2985.2.4.209 to 85.2.4.21485.2.4.2156
15685.2.4.216/2985.2.4.217 to 85.2.4.22285.2.4.2236
15785.2.4.224/2985.2.4.225 to 85.2.4.23085.2.4.2316
15885.2.4.232/2985.2.4.233 to 85.2.4.23885.2.4.2396
15985.2.4.240/2985.2.4.241 to 85.2.4.24685.2.4.2476
16085.2.4.248/2985.2.4.249 to 85.2.4.25485.2.4.2556
16185.2.5.0/2985.2.5.1 to 85.2.5.685.2.5.76
16285.2.5.8/2985.2.5.9 to 85.2.5.1485.2.5.156
16385.2.5.16/2985.2.5.17 to 85.2.5.2285.2.5.236
16485.2.5.24/2985.2.5.25 to 85.2.5.3085.2.5.316
16585.2.5.32/2985.2.5.33 to 85.2.5.3885.2.5.396
16685.2.5.40/2985.2.5.41 to 85.2.5.4685.2.5.476
16785.2.5.48/2985.2.5.49 to 85.2.5.5485.2.5.556
16885.2.5.56/2985.2.5.57 to 85.2.5.6285.2.5.636
16985.2.5.64/2985.2.5.65 to 85.2.5.7085.2.5.716
17085.2.5.72/2985.2.5.73 to 85.2.5.7885.2.5.796
17185.2.5.80/2985.2.5.81 to 85.2.5.8685.2.5.876
17285.2.5.88/2985.2.5.89 to 85.2.5.9485.2.5.956
17385.2.5.96/2985.2.5.97 to 85.2.5.10285.2.5.1036
17485.2.5.104/2985.2.5.105 to 85.2.5.11085.2.5.1116
17585.2.5.112/2985.2.5.113 to 85.2.5.11885.2.5.1196
17685.2.5.120/2985.2.5.121 to 85.2.5.12685.2.5.1276
17785.2.5.128/2985.2.5.129 to 85.2.5.13485.2.5.1356
17885.2.5.136/2985.2.5.137 to 85.2.5.14285.2.5.1436
17985.2.5.144/2985.2.5.145 to 85.2.5.15085.2.5.1516
18085.2.5.152/2985.2.5.153 to 85.2.5.15885.2.5.1596
18185.2.5.160/2985.2.5.161 to 85.2.5.16685.2.5.1676
18285.2.5.168/2985.2.5.169 to 85.2.5.17485.2.5.1756
18385.2.5.176/2985.2.5.177 to 85.2.5.18285.2.5.1836
18485.2.5.184/2985.2.5.185 to 85.2.5.19085.2.5.1916
18585.2.5.192/2985.2.5.193 to 85.2.5.19885.2.5.1996
18685.2.5.200/2985.2.5.201 to 85.2.5.20685.2.5.2076
18785.2.5.208/2985.2.5.209 to 85.2.5.21485.2.5.2156
18885.2.5.216/2985.2.5.217 to 85.2.5.22285.2.5.2236
18985.2.5.224/2985.2.5.225 to 85.2.5.23085.2.5.2316
19085.2.5.232/2985.2.5.233 to 85.2.5.23885.2.5.2396
19185.2.5.240/2985.2.5.241 to 85.2.5.24685.2.5.2476
19285.2.5.248/2985.2.5.249 to 85.2.5.25485.2.5.2556
19385.2.6.0/2985.2.6.1 to 85.2.6.685.2.6.76
19485.2.6.8/2985.2.6.9 to 85.2.6.1485.2.6.156
19585.2.6.16/2985.2.6.17 to 85.2.6.2285.2.6.236
19685.2.6.24/2985.2.6.25 to 85.2.6.3085.2.6.316
19785.2.6.32/2985.2.6.33 to 85.2.6.3885.2.6.396
19885.2.6.40/2985.2.6.41 to 85.2.6.4685.2.6.476
19985.2.6.48/2985.2.6.49 to 85.2.6.5485.2.6.556
20085.2.6.56/2985.2.6.57 to 85.2.6.6285.2.6.636
20185.2.6.64/2985.2.6.65 to 85.2.6.7085.2.6.716
20285.2.6.72/2985.2.6.73 to 85.2.6.7885.2.6.796
20385.2.6.80/2985.2.6.81 to 85.2.6.8685.2.6.876
20485.2.6.88/2985.2.6.89 to 85.2.6.9485.2.6.956
20585.2.6.96/2985.2.6.97 to 85.2.6.10285.2.6.1036
20685.2.6.104/2985.2.6.105 to 85.2.6.11085.2.6.1116
20785.2.6.112/2985.2.6.113 to 85.2.6.11885.2.6.1196
20885.2.6.120/2985.2.6.121 to 85.2.6.12685.2.6.1276
20985.2.6.128/2985.2.6.129 to 85.2.6.13485.2.6.1356
21085.2.6.136/2985.2.6.137 to 85.2.6.14285.2.6.1436
21185.2.6.144/2985.2.6.145 to 85.2.6.15085.2.6.1516
21285.2.6.152/2985.2.6.153 to 85.2.6.15885.2.6.1596
21385.2.6.160/2985.2.6.161 to 85.2.6.16685.2.6.1676
21485.2.6.168/2985.2.6.169 to 85.2.6.17485.2.6.1756
21585.2.6.176/2985.2.6.177 to 85.2.6.18285.2.6.1836
21685.2.6.184/2985.2.6.185 to 85.2.6.19085.2.6.1916
21785.2.6.192/2985.2.6.193 to 85.2.6.19885.2.6.1996
21885.2.6.200/2985.2.6.201 to 85.2.6.20685.2.6.2076
21985.2.6.208/2985.2.6.209 to 85.2.6.21485.2.6.2156
22085.2.6.216/2985.2.6.217 to 85.2.6.22285.2.6.2236
22185.2.6.224/2985.2.6.225 to 85.2.6.23085.2.6.2316
22285.2.6.232/2985.2.6.233 to 85.2.6.23885.2.6.2396
22385.2.6.240/2985.2.6.241 to 85.2.6.24685.2.6.2476
22485.2.6.248/2985.2.6.249 to 85.2.6.25485.2.6.2556
22585.2.7.0/2985.2.7.1 to 85.2.7.685.2.7.76
22685.2.7.8/2985.2.7.9 to 85.2.7.1485.2.7.156
22785.2.7.16/2985.2.7.17 to 85.2.7.2285.2.7.236
22885.2.7.24/2985.2.7.25 to 85.2.7.3085.2.7.316
22985.2.7.32/2985.2.7.33 to 85.2.7.3885.2.7.396
23085.2.7.40/2985.2.7.41 to 85.2.7.4685.2.7.476
23185.2.7.48/2985.2.7.49 to 85.2.7.5485.2.7.556
23285.2.7.56/2985.2.7.57 to 85.2.7.6285.2.7.636
23385.2.7.64/2985.2.7.65 to 85.2.7.7085.2.7.716
23485.2.7.72/2985.2.7.73 to 85.2.7.7885.2.7.796
23585.2.7.80/2985.2.7.81 to 85.2.7.8685.2.7.876
23685.2.7.88/2985.2.7.89 to 85.2.7.9485.2.7.956
23785.2.7.96/2985.2.7.97 to 85.2.7.10285.2.7.1036
23885.2.7.104/2985.2.7.105 to 85.2.7.11085.2.7.1116
23985.2.7.112/2985.2.7.113 to 85.2.7.11885.2.7.1196
24085.2.7.120/2985.2.7.121 to 85.2.7.12685.2.7.1276
24185.2.7.128/2985.2.7.129 to 85.2.7.13485.2.7.1356
24285.2.7.136/2985.2.7.137 to 85.2.7.14285.2.7.1436
24385.2.7.144/2985.2.7.145 to 85.2.7.15085.2.7.1516
24485.2.7.152/2985.2.7.153 to 85.2.7.15885.2.7.1596
24585.2.7.160/2985.2.7.161 to 85.2.7.16685.2.7.1676
24685.2.7.168/2985.2.7.169 to 85.2.7.17485.2.7.1756
24785.2.7.176/2985.2.7.177 to 85.2.7.18285.2.7.1836
24885.2.7.184/2985.2.7.185 to 85.2.7.19085.2.7.1916
24985.2.7.192/2985.2.7.193 to 85.2.7.19885.2.7.1996
25085.2.7.200/2985.2.7.201 to 85.2.7.20685.2.7.2076
25185.2.7.208/2985.2.7.209 to 85.2.7.21485.2.7.2156
25285.2.7.216/2985.2.7.217 to 85.2.7.22285.2.7.2236
25385.2.7.224/2985.2.7.225 to 85.2.7.23085.2.7.2316
25485.2.7.232/2985.2.7.233 to 85.2.7.23885.2.7.2396
25585.2.7.240/2985.2.7.241 to 85.2.7.24685.2.7.2476
25685.2.7.248/2985.2.7.249 to 85.2.7.25485.2.7.2556

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