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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.

Network90.0.64.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
90.0.64.0
Broadcast address
90.0.95.255
First usable
90.0.64.1
Last usable
90.0.95.254
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 5A004000 · Integer 1509965824 to 1509974015
Reverse DNS zones
64.0.90.in-addr.arpa
65.0.90.in-addr.arpa
66.0.90.in-addr.arpa
67.0.90.in-addr.arpa
68.0.90.in-addr.arpa
69.0.90.in-addr.arpa
70.0.90.in-addr.arpa
71.0.90.in-addr.arpa
72.0.90.in-addr.arpa
73.0.90.in-addr.arpa
74.0.90.in-addr.arpa
75.0.90.in-addr.arpa
76.0.90.in-addr.arpa
77.0.90.in-addr.arpa
78.0.90.in-addr.arpa
79.0.90.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
Address01011010.00000000.01000000.0000000090.0.64.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01011010.00000000.01000000.0000000090.0.64.0
Broadcast01011010.00000000.01011111.1111111190.0.95.255
Split into smaller subnets/29

90.0.64.0/19 makes 1,024 subnets of /29; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.0.64.0/2990.0.64.1 to 90.0.64.690.0.64.76
290.0.64.8/2990.0.64.9 to 90.0.64.1490.0.64.156
390.0.64.16/2990.0.64.17 to 90.0.64.2290.0.64.236
490.0.64.24/2990.0.64.25 to 90.0.64.3090.0.64.316
590.0.64.32/2990.0.64.33 to 90.0.64.3890.0.64.396
690.0.64.40/2990.0.64.41 to 90.0.64.4690.0.64.476
790.0.64.48/2990.0.64.49 to 90.0.64.5490.0.64.556
890.0.64.56/2990.0.64.57 to 90.0.64.6290.0.64.636
990.0.64.64/2990.0.64.65 to 90.0.64.7090.0.64.716
1090.0.64.72/2990.0.64.73 to 90.0.64.7890.0.64.796
1190.0.64.80/2990.0.64.81 to 90.0.64.8690.0.64.876
1290.0.64.88/2990.0.64.89 to 90.0.64.9490.0.64.956
1390.0.64.96/2990.0.64.97 to 90.0.64.10290.0.64.1036
1490.0.64.104/2990.0.64.105 to 90.0.64.11090.0.64.1116
1590.0.64.112/2990.0.64.113 to 90.0.64.11890.0.64.1196
1690.0.64.120/2990.0.64.121 to 90.0.64.12690.0.64.1276
1790.0.64.128/2990.0.64.129 to 90.0.64.13490.0.64.1356
1890.0.64.136/2990.0.64.137 to 90.0.64.14290.0.64.1436
1990.0.64.144/2990.0.64.145 to 90.0.64.15090.0.64.1516
2090.0.64.152/2990.0.64.153 to 90.0.64.15890.0.64.1596
2190.0.64.160/2990.0.64.161 to 90.0.64.16690.0.64.1676
2290.0.64.168/2990.0.64.169 to 90.0.64.17490.0.64.1756
2390.0.64.176/2990.0.64.177 to 90.0.64.18290.0.64.1836
2490.0.64.184/2990.0.64.185 to 90.0.64.19090.0.64.1916
2590.0.64.192/2990.0.64.193 to 90.0.64.19890.0.64.1996
2690.0.64.200/2990.0.64.201 to 90.0.64.20690.0.64.2076
2790.0.64.208/2990.0.64.209 to 90.0.64.21490.0.64.2156
2890.0.64.216/2990.0.64.217 to 90.0.64.22290.0.64.2236
2990.0.64.224/2990.0.64.225 to 90.0.64.23090.0.64.2316
3090.0.64.232/2990.0.64.233 to 90.0.64.23890.0.64.2396
3190.0.64.240/2990.0.64.241 to 90.0.64.24690.0.64.2476
3290.0.64.248/2990.0.64.249 to 90.0.64.25490.0.64.2556
3390.0.65.0/2990.0.65.1 to 90.0.65.690.0.65.76
3490.0.65.8/2990.0.65.9 to 90.0.65.1490.0.65.156
3590.0.65.16/2990.0.65.17 to 90.0.65.2290.0.65.236
3690.0.65.24/2990.0.65.25 to 90.0.65.3090.0.65.316
3790.0.65.32/2990.0.65.33 to 90.0.65.3890.0.65.396
3890.0.65.40/2990.0.65.41 to 90.0.65.4690.0.65.476
3990.0.65.48/2990.0.65.49 to 90.0.65.5490.0.65.556
4090.0.65.56/2990.0.65.57 to 90.0.65.6290.0.65.636
4190.0.65.64/2990.0.65.65 to 90.0.65.7090.0.65.716
4290.0.65.72/2990.0.65.73 to 90.0.65.7890.0.65.796
4390.0.65.80/2990.0.65.81 to 90.0.65.8690.0.65.876
4490.0.65.88/2990.0.65.89 to 90.0.65.9490.0.65.956
4590.0.65.96/2990.0.65.97 to 90.0.65.10290.0.65.1036
4690.0.65.104/2990.0.65.105 to 90.0.65.11090.0.65.1116
4790.0.65.112/2990.0.65.113 to 90.0.65.11890.0.65.1196
4890.0.65.120/2990.0.65.121 to 90.0.65.12690.0.65.1276
4990.0.65.128/2990.0.65.129 to 90.0.65.13490.0.65.1356
5090.0.65.136/2990.0.65.137 to 90.0.65.14290.0.65.1436
5190.0.65.144/2990.0.65.145 to 90.0.65.15090.0.65.1516
5290.0.65.152/2990.0.65.153 to 90.0.65.15890.0.65.1596
5390.0.65.160/2990.0.65.161 to 90.0.65.16690.0.65.1676
5490.0.65.168/2990.0.65.169 to 90.0.65.17490.0.65.1756
5590.0.65.176/2990.0.65.177 to 90.0.65.18290.0.65.1836
5690.0.65.184/2990.0.65.185 to 90.0.65.19090.0.65.1916
5790.0.65.192/2990.0.65.193 to 90.0.65.19890.0.65.1996
5890.0.65.200/2990.0.65.201 to 90.0.65.20690.0.65.2076
5990.0.65.208/2990.0.65.209 to 90.0.65.21490.0.65.2156
6090.0.65.216/2990.0.65.217 to 90.0.65.22290.0.65.2236
6190.0.65.224/2990.0.65.225 to 90.0.65.23090.0.65.2316
6290.0.65.232/2990.0.65.233 to 90.0.65.23890.0.65.2396
6390.0.65.240/2990.0.65.241 to 90.0.65.24690.0.65.2476
6490.0.65.248/2990.0.65.249 to 90.0.65.25490.0.65.2556
6590.0.66.0/2990.0.66.1 to 90.0.66.690.0.66.76
6690.0.66.8/2990.0.66.9 to 90.0.66.1490.0.66.156
6790.0.66.16/2990.0.66.17 to 90.0.66.2290.0.66.236
6890.0.66.24/2990.0.66.25 to 90.0.66.3090.0.66.316
6990.0.66.32/2990.0.66.33 to 90.0.66.3890.0.66.396
7090.0.66.40/2990.0.66.41 to 90.0.66.4690.0.66.476
7190.0.66.48/2990.0.66.49 to 90.0.66.5490.0.66.556
7290.0.66.56/2990.0.66.57 to 90.0.66.6290.0.66.636
7390.0.66.64/2990.0.66.65 to 90.0.66.7090.0.66.716
7490.0.66.72/2990.0.66.73 to 90.0.66.7890.0.66.796
7590.0.66.80/2990.0.66.81 to 90.0.66.8690.0.66.876
7690.0.66.88/2990.0.66.89 to 90.0.66.9490.0.66.956
7790.0.66.96/2990.0.66.97 to 90.0.66.10290.0.66.1036
7890.0.66.104/2990.0.66.105 to 90.0.66.11090.0.66.1116
7990.0.66.112/2990.0.66.113 to 90.0.66.11890.0.66.1196
8090.0.66.120/2990.0.66.121 to 90.0.66.12690.0.66.1276
8190.0.66.128/2990.0.66.129 to 90.0.66.13490.0.66.1356
8290.0.66.136/2990.0.66.137 to 90.0.66.14290.0.66.1436
8390.0.66.144/2990.0.66.145 to 90.0.66.15090.0.66.1516
8490.0.66.152/2990.0.66.153 to 90.0.66.15890.0.66.1596
8590.0.66.160/2990.0.66.161 to 90.0.66.16690.0.66.1676
8690.0.66.168/2990.0.66.169 to 90.0.66.17490.0.66.1756
8790.0.66.176/2990.0.66.177 to 90.0.66.18290.0.66.1836
8890.0.66.184/2990.0.66.185 to 90.0.66.19090.0.66.1916
8990.0.66.192/2990.0.66.193 to 90.0.66.19890.0.66.1996
9090.0.66.200/2990.0.66.201 to 90.0.66.20690.0.66.2076
9190.0.66.208/2990.0.66.209 to 90.0.66.21490.0.66.2156
9290.0.66.216/2990.0.66.217 to 90.0.66.22290.0.66.2236
9390.0.66.224/2990.0.66.225 to 90.0.66.23090.0.66.2316
9490.0.66.232/2990.0.66.233 to 90.0.66.23890.0.66.2396
9590.0.66.240/2990.0.66.241 to 90.0.66.24690.0.66.2476
9690.0.66.248/2990.0.66.249 to 90.0.66.25490.0.66.2556
9790.0.67.0/2990.0.67.1 to 90.0.67.690.0.67.76
9890.0.67.8/2990.0.67.9 to 90.0.67.1490.0.67.156
9990.0.67.16/2990.0.67.17 to 90.0.67.2290.0.67.236
10090.0.67.24/2990.0.67.25 to 90.0.67.3090.0.67.316
10190.0.67.32/2990.0.67.33 to 90.0.67.3890.0.67.396
10290.0.67.40/2990.0.67.41 to 90.0.67.4690.0.67.476
10390.0.67.48/2990.0.67.49 to 90.0.67.5490.0.67.556
10490.0.67.56/2990.0.67.57 to 90.0.67.6290.0.67.636
10590.0.67.64/2990.0.67.65 to 90.0.67.7090.0.67.716
10690.0.67.72/2990.0.67.73 to 90.0.67.7890.0.67.796
10790.0.67.80/2990.0.67.81 to 90.0.67.8690.0.67.876
10890.0.67.88/2990.0.67.89 to 90.0.67.9490.0.67.956
10990.0.67.96/2990.0.67.97 to 90.0.67.10290.0.67.1036
11090.0.67.104/2990.0.67.105 to 90.0.67.11090.0.67.1116
11190.0.67.112/2990.0.67.113 to 90.0.67.11890.0.67.1196
11290.0.67.120/2990.0.67.121 to 90.0.67.12690.0.67.1276
11390.0.67.128/2990.0.67.129 to 90.0.67.13490.0.67.1356
11490.0.67.136/2990.0.67.137 to 90.0.67.14290.0.67.1436
11590.0.67.144/2990.0.67.145 to 90.0.67.15090.0.67.1516
11690.0.67.152/2990.0.67.153 to 90.0.67.15890.0.67.1596
11790.0.67.160/2990.0.67.161 to 90.0.67.16690.0.67.1676
11890.0.67.168/2990.0.67.169 to 90.0.67.17490.0.67.1756
11990.0.67.176/2990.0.67.177 to 90.0.67.18290.0.67.1836
12090.0.67.184/2990.0.67.185 to 90.0.67.19090.0.67.1916
12190.0.67.192/2990.0.67.193 to 90.0.67.19890.0.67.1996
12290.0.67.200/2990.0.67.201 to 90.0.67.20690.0.67.2076
12390.0.67.208/2990.0.67.209 to 90.0.67.21490.0.67.2156
12490.0.67.216/2990.0.67.217 to 90.0.67.22290.0.67.2236
12590.0.67.224/2990.0.67.225 to 90.0.67.23090.0.67.2316
12690.0.67.232/2990.0.67.233 to 90.0.67.23890.0.67.2396
12790.0.67.240/2990.0.67.241 to 90.0.67.24690.0.67.2476
12890.0.67.248/2990.0.67.249 to 90.0.67.25490.0.67.2556
12990.0.68.0/2990.0.68.1 to 90.0.68.690.0.68.76
13090.0.68.8/2990.0.68.9 to 90.0.68.1490.0.68.156
13190.0.68.16/2990.0.68.17 to 90.0.68.2290.0.68.236
13290.0.68.24/2990.0.68.25 to 90.0.68.3090.0.68.316
13390.0.68.32/2990.0.68.33 to 90.0.68.3890.0.68.396
13490.0.68.40/2990.0.68.41 to 90.0.68.4690.0.68.476
13590.0.68.48/2990.0.68.49 to 90.0.68.5490.0.68.556
13690.0.68.56/2990.0.68.57 to 90.0.68.6290.0.68.636
13790.0.68.64/2990.0.68.65 to 90.0.68.7090.0.68.716
13890.0.68.72/2990.0.68.73 to 90.0.68.7890.0.68.796
13990.0.68.80/2990.0.68.81 to 90.0.68.8690.0.68.876
14090.0.68.88/2990.0.68.89 to 90.0.68.9490.0.68.956
14190.0.68.96/2990.0.68.97 to 90.0.68.10290.0.68.1036
14290.0.68.104/2990.0.68.105 to 90.0.68.11090.0.68.1116
14390.0.68.112/2990.0.68.113 to 90.0.68.11890.0.68.1196
14490.0.68.120/2990.0.68.121 to 90.0.68.12690.0.68.1276
14590.0.68.128/2990.0.68.129 to 90.0.68.13490.0.68.1356
14690.0.68.136/2990.0.68.137 to 90.0.68.14290.0.68.1436
14790.0.68.144/2990.0.68.145 to 90.0.68.15090.0.68.1516
14890.0.68.152/2990.0.68.153 to 90.0.68.15890.0.68.1596
14990.0.68.160/2990.0.68.161 to 90.0.68.16690.0.68.1676
15090.0.68.168/2990.0.68.169 to 90.0.68.17490.0.68.1756
15190.0.68.176/2990.0.68.177 to 90.0.68.18290.0.68.1836
15290.0.68.184/2990.0.68.185 to 90.0.68.19090.0.68.1916
15390.0.68.192/2990.0.68.193 to 90.0.68.19890.0.68.1996
15490.0.68.200/2990.0.68.201 to 90.0.68.20690.0.68.2076
15590.0.68.208/2990.0.68.209 to 90.0.68.21490.0.68.2156
15690.0.68.216/2990.0.68.217 to 90.0.68.22290.0.68.2236
15790.0.68.224/2990.0.68.225 to 90.0.68.23090.0.68.2316
15890.0.68.232/2990.0.68.233 to 90.0.68.23890.0.68.2396
15990.0.68.240/2990.0.68.241 to 90.0.68.24690.0.68.2476
16090.0.68.248/2990.0.68.249 to 90.0.68.25490.0.68.2556
16190.0.69.0/2990.0.69.1 to 90.0.69.690.0.69.76
16290.0.69.8/2990.0.69.9 to 90.0.69.1490.0.69.156
16390.0.69.16/2990.0.69.17 to 90.0.69.2290.0.69.236
16490.0.69.24/2990.0.69.25 to 90.0.69.3090.0.69.316
16590.0.69.32/2990.0.69.33 to 90.0.69.3890.0.69.396
16690.0.69.40/2990.0.69.41 to 90.0.69.4690.0.69.476
16790.0.69.48/2990.0.69.49 to 90.0.69.5490.0.69.556
16890.0.69.56/2990.0.69.57 to 90.0.69.6290.0.69.636
16990.0.69.64/2990.0.69.65 to 90.0.69.7090.0.69.716
17090.0.69.72/2990.0.69.73 to 90.0.69.7890.0.69.796
17190.0.69.80/2990.0.69.81 to 90.0.69.8690.0.69.876
17290.0.69.88/2990.0.69.89 to 90.0.69.9490.0.69.956
17390.0.69.96/2990.0.69.97 to 90.0.69.10290.0.69.1036
17490.0.69.104/2990.0.69.105 to 90.0.69.11090.0.69.1116
17590.0.69.112/2990.0.69.113 to 90.0.69.11890.0.69.1196
17690.0.69.120/2990.0.69.121 to 90.0.69.12690.0.69.1276
17790.0.69.128/2990.0.69.129 to 90.0.69.13490.0.69.1356
17890.0.69.136/2990.0.69.137 to 90.0.69.14290.0.69.1436
17990.0.69.144/2990.0.69.145 to 90.0.69.15090.0.69.1516
18090.0.69.152/2990.0.69.153 to 90.0.69.15890.0.69.1596
18190.0.69.160/2990.0.69.161 to 90.0.69.16690.0.69.1676
18290.0.69.168/2990.0.69.169 to 90.0.69.17490.0.69.1756
18390.0.69.176/2990.0.69.177 to 90.0.69.18290.0.69.1836
18490.0.69.184/2990.0.69.185 to 90.0.69.19090.0.69.1916
18590.0.69.192/2990.0.69.193 to 90.0.69.19890.0.69.1996
18690.0.69.200/2990.0.69.201 to 90.0.69.20690.0.69.2076
18790.0.69.208/2990.0.69.209 to 90.0.69.21490.0.69.2156
18890.0.69.216/2990.0.69.217 to 90.0.69.22290.0.69.2236
18990.0.69.224/2990.0.69.225 to 90.0.69.23090.0.69.2316
19090.0.69.232/2990.0.69.233 to 90.0.69.23890.0.69.2396
19190.0.69.240/2990.0.69.241 to 90.0.69.24690.0.69.2476
19290.0.69.248/2990.0.69.249 to 90.0.69.25490.0.69.2556
19390.0.70.0/2990.0.70.1 to 90.0.70.690.0.70.76
19490.0.70.8/2990.0.70.9 to 90.0.70.1490.0.70.156
19590.0.70.16/2990.0.70.17 to 90.0.70.2290.0.70.236
19690.0.70.24/2990.0.70.25 to 90.0.70.3090.0.70.316
19790.0.70.32/2990.0.70.33 to 90.0.70.3890.0.70.396
19890.0.70.40/2990.0.70.41 to 90.0.70.4690.0.70.476
19990.0.70.48/2990.0.70.49 to 90.0.70.5490.0.70.556
20090.0.70.56/2990.0.70.57 to 90.0.70.6290.0.70.636
20190.0.70.64/2990.0.70.65 to 90.0.70.7090.0.70.716
20290.0.70.72/2990.0.70.73 to 90.0.70.7890.0.70.796
20390.0.70.80/2990.0.70.81 to 90.0.70.8690.0.70.876
20490.0.70.88/2990.0.70.89 to 90.0.70.9490.0.70.956
20590.0.70.96/2990.0.70.97 to 90.0.70.10290.0.70.1036
20690.0.70.104/2990.0.70.105 to 90.0.70.11090.0.70.1116
20790.0.70.112/2990.0.70.113 to 90.0.70.11890.0.70.1196
20890.0.70.120/2990.0.70.121 to 90.0.70.12690.0.70.1276
20990.0.70.128/2990.0.70.129 to 90.0.70.13490.0.70.1356
21090.0.70.136/2990.0.70.137 to 90.0.70.14290.0.70.1436
21190.0.70.144/2990.0.70.145 to 90.0.70.15090.0.70.1516
21290.0.70.152/2990.0.70.153 to 90.0.70.15890.0.70.1596
21390.0.70.160/2990.0.70.161 to 90.0.70.16690.0.70.1676
21490.0.70.168/2990.0.70.169 to 90.0.70.17490.0.70.1756
21590.0.70.176/2990.0.70.177 to 90.0.70.18290.0.70.1836
21690.0.70.184/2990.0.70.185 to 90.0.70.19090.0.70.1916
21790.0.70.192/2990.0.70.193 to 90.0.70.19890.0.70.1996
21890.0.70.200/2990.0.70.201 to 90.0.70.20690.0.70.2076
21990.0.70.208/2990.0.70.209 to 90.0.70.21490.0.70.2156
22090.0.70.216/2990.0.70.217 to 90.0.70.22290.0.70.2236
22190.0.70.224/2990.0.70.225 to 90.0.70.23090.0.70.2316
22290.0.70.232/2990.0.70.233 to 90.0.70.23890.0.70.2396
22390.0.70.240/2990.0.70.241 to 90.0.70.24690.0.70.2476
22490.0.70.248/2990.0.70.249 to 90.0.70.25490.0.70.2556
22590.0.71.0/2990.0.71.1 to 90.0.71.690.0.71.76
22690.0.71.8/2990.0.71.9 to 90.0.71.1490.0.71.156
22790.0.71.16/2990.0.71.17 to 90.0.71.2290.0.71.236
22890.0.71.24/2990.0.71.25 to 90.0.71.3090.0.71.316
22990.0.71.32/2990.0.71.33 to 90.0.71.3890.0.71.396
23090.0.71.40/2990.0.71.41 to 90.0.71.4690.0.71.476
23190.0.71.48/2990.0.71.49 to 90.0.71.5490.0.71.556
23290.0.71.56/2990.0.71.57 to 90.0.71.6290.0.71.636
23390.0.71.64/2990.0.71.65 to 90.0.71.7090.0.71.716
23490.0.71.72/2990.0.71.73 to 90.0.71.7890.0.71.796
23590.0.71.80/2990.0.71.81 to 90.0.71.8690.0.71.876
23690.0.71.88/2990.0.71.89 to 90.0.71.9490.0.71.956
23790.0.71.96/2990.0.71.97 to 90.0.71.10290.0.71.1036
23890.0.71.104/2990.0.71.105 to 90.0.71.11090.0.71.1116
23990.0.71.112/2990.0.71.113 to 90.0.71.11890.0.71.1196
24090.0.71.120/2990.0.71.121 to 90.0.71.12690.0.71.1276
24190.0.71.128/2990.0.71.129 to 90.0.71.13490.0.71.1356
24290.0.71.136/2990.0.71.137 to 90.0.71.14290.0.71.1436
24390.0.71.144/2990.0.71.145 to 90.0.71.15090.0.71.1516
24490.0.71.152/2990.0.71.153 to 90.0.71.15890.0.71.1596
24590.0.71.160/2990.0.71.161 to 90.0.71.16690.0.71.1676
24690.0.71.168/2990.0.71.169 to 90.0.71.17490.0.71.1756
24790.0.71.176/2990.0.71.177 to 90.0.71.18290.0.71.1836
24890.0.71.184/2990.0.71.185 to 90.0.71.19090.0.71.1916
24990.0.71.192/2990.0.71.193 to 90.0.71.19890.0.71.1996
25090.0.71.200/2990.0.71.201 to 90.0.71.20690.0.71.2076
25190.0.71.208/2990.0.71.209 to 90.0.71.21490.0.71.2156
25290.0.71.216/2990.0.71.217 to 90.0.71.22290.0.71.2236
25390.0.71.224/2990.0.71.225 to 90.0.71.23090.0.71.2316
25490.0.71.232/2990.0.71.233 to 90.0.71.23890.0.71.2396
25590.0.71.240/2990.0.71.241 to 90.0.71.24690.0.71.2476
25690.0.71.248/2990.0.71.249 to 90.0.71.25490.0.71.2556

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