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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.

Network47.2.52.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
47.2.52.0
Broadcast address
47.2.55.255
First usable
47.2.52.1
Last usable
47.2.55.254
Usable hosts
1,022 (1,024 less the network and broadcast addresses)
Subnet mask
255.255.252.0
Wildcard mask
0.0.3.255 (Cisco ACLs, OSPF)
Prefix length
/22
Type
Public public
Old class
A (default /8)
As numbers
Hex 2F023400 · Integer 788673536 to 788674559
Reverse DNS zones
52.2.47.in-addr.arpa
53.2.47.in-addr.arpa
54.2.47.in-addr.arpa
55.2.47.in-addr.arpa
/22 is not on a 8-bit boundary, so it takes 4 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101111.00000010.00110100.0000000047.2.52.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00101111.00000010.00110100.0000000047.2.52.0
Broadcast00101111.00000010.00110111.1111111147.2.55.255
Split into smaller subnets/30
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

47.2.52.0/22 makes 256 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.2.52.0/3047.2.52.1 to 47.2.52.247.2.52.32
247.2.52.4/3047.2.52.5 to 47.2.52.647.2.52.72
347.2.52.8/3047.2.52.9 to 47.2.52.1047.2.52.112
447.2.52.12/3047.2.52.13 to 47.2.52.1447.2.52.152
547.2.52.16/3047.2.52.17 to 47.2.52.1847.2.52.192
647.2.52.20/3047.2.52.21 to 47.2.52.2247.2.52.232
747.2.52.24/3047.2.52.25 to 47.2.52.2647.2.52.272
847.2.52.28/3047.2.52.29 to 47.2.52.3047.2.52.312
947.2.52.32/3047.2.52.33 to 47.2.52.3447.2.52.352
1047.2.52.36/3047.2.52.37 to 47.2.52.3847.2.52.392
1147.2.52.40/3047.2.52.41 to 47.2.52.4247.2.52.432
1247.2.52.44/3047.2.52.45 to 47.2.52.4647.2.52.472
1347.2.52.48/3047.2.52.49 to 47.2.52.5047.2.52.512
1447.2.52.52/3047.2.52.53 to 47.2.52.5447.2.52.552
1547.2.52.56/3047.2.52.57 to 47.2.52.5847.2.52.592
1647.2.52.60/3047.2.52.61 to 47.2.52.6247.2.52.632
1747.2.52.64/3047.2.52.65 to 47.2.52.6647.2.52.672
1847.2.52.68/3047.2.52.69 to 47.2.52.7047.2.52.712
1947.2.52.72/3047.2.52.73 to 47.2.52.7447.2.52.752
2047.2.52.76/3047.2.52.77 to 47.2.52.7847.2.52.792
2147.2.52.80/3047.2.52.81 to 47.2.52.8247.2.52.832
2247.2.52.84/3047.2.52.85 to 47.2.52.8647.2.52.872
2347.2.52.88/3047.2.52.89 to 47.2.52.9047.2.52.912
2447.2.52.92/3047.2.52.93 to 47.2.52.9447.2.52.952
2547.2.52.96/3047.2.52.97 to 47.2.52.9847.2.52.992
2647.2.52.100/3047.2.52.101 to 47.2.52.10247.2.52.1032
2747.2.52.104/3047.2.52.105 to 47.2.52.10647.2.52.1072
2847.2.52.108/3047.2.52.109 to 47.2.52.11047.2.52.1112
2947.2.52.112/3047.2.52.113 to 47.2.52.11447.2.52.1152
3047.2.52.116/3047.2.52.117 to 47.2.52.11847.2.52.1192
3147.2.52.120/3047.2.52.121 to 47.2.52.12247.2.52.1232
3247.2.52.124/3047.2.52.125 to 47.2.52.12647.2.52.1272
3347.2.52.128/3047.2.52.129 to 47.2.52.13047.2.52.1312
3447.2.52.132/3047.2.52.133 to 47.2.52.13447.2.52.1352
3547.2.52.136/3047.2.52.137 to 47.2.52.13847.2.52.1392
3647.2.52.140/3047.2.52.141 to 47.2.52.14247.2.52.1432
3747.2.52.144/3047.2.52.145 to 47.2.52.14647.2.52.1472
3847.2.52.148/3047.2.52.149 to 47.2.52.15047.2.52.1512
3947.2.52.152/3047.2.52.153 to 47.2.52.15447.2.52.1552
4047.2.52.156/3047.2.52.157 to 47.2.52.15847.2.52.1592
4147.2.52.160/3047.2.52.161 to 47.2.52.16247.2.52.1632
4247.2.52.164/3047.2.52.165 to 47.2.52.16647.2.52.1672
4347.2.52.168/3047.2.52.169 to 47.2.52.17047.2.52.1712
4447.2.52.172/3047.2.52.173 to 47.2.52.17447.2.52.1752
4547.2.52.176/3047.2.52.177 to 47.2.52.17847.2.52.1792
4647.2.52.180/3047.2.52.181 to 47.2.52.18247.2.52.1832
4747.2.52.184/3047.2.52.185 to 47.2.52.18647.2.52.1872
4847.2.52.188/3047.2.52.189 to 47.2.52.19047.2.52.1912
4947.2.52.192/3047.2.52.193 to 47.2.52.19447.2.52.1952
5047.2.52.196/3047.2.52.197 to 47.2.52.19847.2.52.1992
5147.2.52.200/3047.2.52.201 to 47.2.52.20247.2.52.2032
5247.2.52.204/3047.2.52.205 to 47.2.52.20647.2.52.2072
5347.2.52.208/3047.2.52.209 to 47.2.52.21047.2.52.2112
5447.2.52.212/3047.2.52.213 to 47.2.52.21447.2.52.2152
5547.2.52.216/3047.2.52.217 to 47.2.52.21847.2.52.2192
5647.2.52.220/3047.2.52.221 to 47.2.52.22247.2.52.2232
5747.2.52.224/3047.2.52.225 to 47.2.52.22647.2.52.2272
5847.2.52.228/3047.2.52.229 to 47.2.52.23047.2.52.2312
5947.2.52.232/3047.2.52.233 to 47.2.52.23447.2.52.2352
6047.2.52.236/3047.2.52.237 to 47.2.52.23847.2.52.2392
6147.2.52.240/3047.2.52.241 to 47.2.52.24247.2.52.2432
6247.2.52.244/3047.2.52.245 to 47.2.52.24647.2.52.2472
6347.2.52.248/3047.2.52.249 to 47.2.52.25047.2.52.2512
6447.2.52.252/3047.2.52.253 to 47.2.52.25447.2.52.2552
6547.2.53.0/3047.2.53.1 to 47.2.53.247.2.53.32
6647.2.53.4/3047.2.53.5 to 47.2.53.647.2.53.72
6747.2.53.8/3047.2.53.9 to 47.2.53.1047.2.53.112
6847.2.53.12/3047.2.53.13 to 47.2.53.1447.2.53.152
6947.2.53.16/3047.2.53.17 to 47.2.53.1847.2.53.192
7047.2.53.20/3047.2.53.21 to 47.2.53.2247.2.53.232
7147.2.53.24/3047.2.53.25 to 47.2.53.2647.2.53.272
7247.2.53.28/3047.2.53.29 to 47.2.53.3047.2.53.312
7347.2.53.32/3047.2.53.33 to 47.2.53.3447.2.53.352
7447.2.53.36/3047.2.53.37 to 47.2.53.3847.2.53.392
7547.2.53.40/3047.2.53.41 to 47.2.53.4247.2.53.432
7647.2.53.44/3047.2.53.45 to 47.2.53.4647.2.53.472
7747.2.53.48/3047.2.53.49 to 47.2.53.5047.2.53.512
7847.2.53.52/3047.2.53.53 to 47.2.53.5447.2.53.552
7947.2.53.56/3047.2.53.57 to 47.2.53.5847.2.53.592
8047.2.53.60/3047.2.53.61 to 47.2.53.6247.2.53.632
8147.2.53.64/3047.2.53.65 to 47.2.53.6647.2.53.672
8247.2.53.68/3047.2.53.69 to 47.2.53.7047.2.53.712
8347.2.53.72/3047.2.53.73 to 47.2.53.7447.2.53.752
8447.2.53.76/3047.2.53.77 to 47.2.53.7847.2.53.792
8547.2.53.80/3047.2.53.81 to 47.2.53.8247.2.53.832
8647.2.53.84/3047.2.53.85 to 47.2.53.8647.2.53.872
8747.2.53.88/3047.2.53.89 to 47.2.53.9047.2.53.912
8847.2.53.92/3047.2.53.93 to 47.2.53.9447.2.53.952
8947.2.53.96/3047.2.53.97 to 47.2.53.9847.2.53.992
9047.2.53.100/3047.2.53.101 to 47.2.53.10247.2.53.1032
9147.2.53.104/3047.2.53.105 to 47.2.53.10647.2.53.1072
9247.2.53.108/3047.2.53.109 to 47.2.53.11047.2.53.1112
9347.2.53.112/3047.2.53.113 to 47.2.53.11447.2.53.1152
9447.2.53.116/3047.2.53.117 to 47.2.53.11847.2.53.1192
9547.2.53.120/3047.2.53.121 to 47.2.53.12247.2.53.1232
9647.2.53.124/3047.2.53.125 to 47.2.53.12647.2.53.1272
9747.2.53.128/3047.2.53.129 to 47.2.53.13047.2.53.1312
9847.2.53.132/3047.2.53.133 to 47.2.53.13447.2.53.1352
9947.2.53.136/3047.2.53.137 to 47.2.53.13847.2.53.1392
10047.2.53.140/3047.2.53.141 to 47.2.53.14247.2.53.1432
10147.2.53.144/3047.2.53.145 to 47.2.53.14647.2.53.1472
10247.2.53.148/3047.2.53.149 to 47.2.53.15047.2.53.1512
10347.2.53.152/3047.2.53.153 to 47.2.53.15447.2.53.1552
10447.2.53.156/3047.2.53.157 to 47.2.53.15847.2.53.1592
10547.2.53.160/3047.2.53.161 to 47.2.53.16247.2.53.1632
10647.2.53.164/3047.2.53.165 to 47.2.53.16647.2.53.1672
10747.2.53.168/3047.2.53.169 to 47.2.53.17047.2.53.1712
10847.2.53.172/3047.2.53.173 to 47.2.53.17447.2.53.1752
10947.2.53.176/3047.2.53.177 to 47.2.53.17847.2.53.1792
11047.2.53.180/3047.2.53.181 to 47.2.53.18247.2.53.1832
11147.2.53.184/3047.2.53.185 to 47.2.53.18647.2.53.1872
11247.2.53.188/3047.2.53.189 to 47.2.53.19047.2.53.1912
11347.2.53.192/3047.2.53.193 to 47.2.53.19447.2.53.1952
11447.2.53.196/3047.2.53.197 to 47.2.53.19847.2.53.1992
11547.2.53.200/3047.2.53.201 to 47.2.53.20247.2.53.2032
11647.2.53.204/3047.2.53.205 to 47.2.53.20647.2.53.2072
11747.2.53.208/3047.2.53.209 to 47.2.53.21047.2.53.2112
11847.2.53.212/3047.2.53.213 to 47.2.53.21447.2.53.2152
11947.2.53.216/3047.2.53.217 to 47.2.53.21847.2.53.2192
12047.2.53.220/3047.2.53.221 to 47.2.53.22247.2.53.2232
12147.2.53.224/3047.2.53.225 to 47.2.53.22647.2.53.2272
12247.2.53.228/3047.2.53.229 to 47.2.53.23047.2.53.2312
12347.2.53.232/3047.2.53.233 to 47.2.53.23447.2.53.2352
12447.2.53.236/3047.2.53.237 to 47.2.53.23847.2.53.2392
12547.2.53.240/3047.2.53.241 to 47.2.53.24247.2.53.2432
12647.2.53.244/3047.2.53.245 to 47.2.53.24647.2.53.2472
12747.2.53.248/3047.2.53.249 to 47.2.53.25047.2.53.2512
12847.2.53.252/3047.2.53.253 to 47.2.53.25447.2.53.2552
12947.2.54.0/3047.2.54.1 to 47.2.54.247.2.54.32
13047.2.54.4/3047.2.54.5 to 47.2.54.647.2.54.72
13147.2.54.8/3047.2.54.9 to 47.2.54.1047.2.54.112
13247.2.54.12/3047.2.54.13 to 47.2.54.1447.2.54.152
13347.2.54.16/3047.2.54.17 to 47.2.54.1847.2.54.192
13447.2.54.20/3047.2.54.21 to 47.2.54.2247.2.54.232
13547.2.54.24/3047.2.54.25 to 47.2.54.2647.2.54.272
13647.2.54.28/3047.2.54.29 to 47.2.54.3047.2.54.312
13747.2.54.32/3047.2.54.33 to 47.2.54.3447.2.54.352
13847.2.54.36/3047.2.54.37 to 47.2.54.3847.2.54.392
13947.2.54.40/3047.2.54.41 to 47.2.54.4247.2.54.432
14047.2.54.44/3047.2.54.45 to 47.2.54.4647.2.54.472
14147.2.54.48/3047.2.54.49 to 47.2.54.5047.2.54.512
14247.2.54.52/3047.2.54.53 to 47.2.54.5447.2.54.552
14347.2.54.56/3047.2.54.57 to 47.2.54.5847.2.54.592
14447.2.54.60/3047.2.54.61 to 47.2.54.6247.2.54.632
14547.2.54.64/3047.2.54.65 to 47.2.54.6647.2.54.672
14647.2.54.68/3047.2.54.69 to 47.2.54.7047.2.54.712
14747.2.54.72/3047.2.54.73 to 47.2.54.7447.2.54.752
14847.2.54.76/3047.2.54.77 to 47.2.54.7847.2.54.792
14947.2.54.80/3047.2.54.81 to 47.2.54.8247.2.54.832
15047.2.54.84/3047.2.54.85 to 47.2.54.8647.2.54.872
15147.2.54.88/3047.2.54.89 to 47.2.54.9047.2.54.912
15247.2.54.92/3047.2.54.93 to 47.2.54.9447.2.54.952
15347.2.54.96/3047.2.54.97 to 47.2.54.9847.2.54.992
15447.2.54.100/3047.2.54.101 to 47.2.54.10247.2.54.1032
15547.2.54.104/3047.2.54.105 to 47.2.54.10647.2.54.1072
15647.2.54.108/3047.2.54.109 to 47.2.54.11047.2.54.1112
15747.2.54.112/3047.2.54.113 to 47.2.54.11447.2.54.1152
15847.2.54.116/3047.2.54.117 to 47.2.54.11847.2.54.1192
15947.2.54.120/3047.2.54.121 to 47.2.54.12247.2.54.1232
16047.2.54.124/3047.2.54.125 to 47.2.54.12647.2.54.1272
16147.2.54.128/3047.2.54.129 to 47.2.54.13047.2.54.1312
16247.2.54.132/3047.2.54.133 to 47.2.54.13447.2.54.1352
16347.2.54.136/3047.2.54.137 to 47.2.54.13847.2.54.1392
16447.2.54.140/3047.2.54.141 to 47.2.54.14247.2.54.1432
16547.2.54.144/3047.2.54.145 to 47.2.54.14647.2.54.1472
16647.2.54.148/3047.2.54.149 to 47.2.54.15047.2.54.1512
16747.2.54.152/3047.2.54.153 to 47.2.54.15447.2.54.1552
16847.2.54.156/3047.2.54.157 to 47.2.54.15847.2.54.1592
16947.2.54.160/3047.2.54.161 to 47.2.54.16247.2.54.1632
17047.2.54.164/3047.2.54.165 to 47.2.54.16647.2.54.1672
17147.2.54.168/3047.2.54.169 to 47.2.54.17047.2.54.1712
17247.2.54.172/3047.2.54.173 to 47.2.54.17447.2.54.1752
17347.2.54.176/3047.2.54.177 to 47.2.54.17847.2.54.1792
17447.2.54.180/3047.2.54.181 to 47.2.54.18247.2.54.1832
17547.2.54.184/3047.2.54.185 to 47.2.54.18647.2.54.1872
17647.2.54.188/3047.2.54.189 to 47.2.54.19047.2.54.1912
17747.2.54.192/3047.2.54.193 to 47.2.54.19447.2.54.1952
17847.2.54.196/3047.2.54.197 to 47.2.54.19847.2.54.1992
17947.2.54.200/3047.2.54.201 to 47.2.54.20247.2.54.2032
18047.2.54.204/3047.2.54.205 to 47.2.54.20647.2.54.2072
18147.2.54.208/3047.2.54.209 to 47.2.54.21047.2.54.2112
18247.2.54.212/3047.2.54.213 to 47.2.54.21447.2.54.2152
18347.2.54.216/3047.2.54.217 to 47.2.54.21847.2.54.2192
18447.2.54.220/3047.2.54.221 to 47.2.54.22247.2.54.2232
18547.2.54.224/3047.2.54.225 to 47.2.54.22647.2.54.2272
18647.2.54.228/3047.2.54.229 to 47.2.54.23047.2.54.2312
18747.2.54.232/3047.2.54.233 to 47.2.54.23447.2.54.2352
18847.2.54.236/3047.2.54.237 to 47.2.54.23847.2.54.2392
18947.2.54.240/3047.2.54.241 to 47.2.54.24247.2.54.2432
19047.2.54.244/3047.2.54.245 to 47.2.54.24647.2.54.2472
19147.2.54.248/3047.2.54.249 to 47.2.54.25047.2.54.2512
19247.2.54.252/3047.2.54.253 to 47.2.54.25447.2.54.2552
19347.2.55.0/3047.2.55.1 to 47.2.55.247.2.55.32
19447.2.55.4/3047.2.55.5 to 47.2.55.647.2.55.72
19547.2.55.8/3047.2.55.9 to 47.2.55.1047.2.55.112
19647.2.55.12/3047.2.55.13 to 47.2.55.1447.2.55.152
19747.2.55.16/3047.2.55.17 to 47.2.55.1847.2.55.192
19847.2.55.20/3047.2.55.21 to 47.2.55.2247.2.55.232
19947.2.55.24/3047.2.55.25 to 47.2.55.2647.2.55.272
20047.2.55.28/3047.2.55.29 to 47.2.55.3047.2.55.312
20147.2.55.32/3047.2.55.33 to 47.2.55.3447.2.55.352
20247.2.55.36/3047.2.55.37 to 47.2.55.3847.2.55.392
20347.2.55.40/3047.2.55.41 to 47.2.55.4247.2.55.432
20447.2.55.44/3047.2.55.45 to 47.2.55.4647.2.55.472
20547.2.55.48/3047.2.55.49 to 47.2.55.5047.2.55.512
20647.2.55.52/3047.2.55.53 to 47.2.55.5447.2.55.552
20747.2.55.56/3047.2.55.57 to 47.2.55.5847.2.55.592
20847.2.55.60/3047.2.55.61 to 47.2.55.6247.2.55.632
20947.2.55.64/3047.2.55.65 to 47.2.55.6647.2.55.672
21047.2.55.68/3047.2.55.69 to 47.2.55.7047.2.55.712
21147.2.55.72/3047.2.55.73 to 47.2.55.7447.2.55.752
21247.2.55.76/3047.2.55.77 to 47.2.55.7847.2.55.792
21347.2.55.80/3047.2.55.81 to 47.2.55.8247.2.55.832
21447.2.55.84/3047.2.55.85 to 47.2.55.8647.2.55.872
21547.2.55.88/3047.2.55.89 to 47.2.55.9047.2.55.912
21647.2.55.92/3047.2.55.93 to 47.2.55.9447.2.55.952
21747.2.55.96/3047.2.55.97 to 47.2.55.9847.2.55.992
21847.2.55.100/3047.2.55.101 to 47.2.55.10247.2.55.1032
21947.2.55.104/3047.2.55.105 to 47.2.55.10647.2.55.1072
22047.2.55.108/3047.2.55.109 to 47.2.55.11047.2.55.1112
22147.2.55.112/3047.2.55.113 to 47.2.55.11447.2.55.1152
22247.2.55.116/3047.2.55.117 to 47.2.55.11847.2.55.1192
22347.2.55.120/3047.2.55.121 to 47.2.55.12247.2.55.1232
22447.2.55.124/3047.2.55.125 to 47.2.55.12647.2.55.1272
22547.2.55.128/3047.2.55.129 to 47.2.55.13047.2.55.1312
22647.2.55.132/3047.2.55.133 to 47.2.55.13447.2.55.1352
22747.2.55.136/3047.2.55.137 to 47.2.55.13847.2.55.1392
22847.2.55.140/3047.2.55.141 to 47.2.55.14247.2.55.1432
22947.2.55.144/3047.2.55.145 to 47.2.55.14647.2.55.1472
23047.2.55.148/3047.2.55.149 to 47.2.55.15047.2.55.1512
23147.2.55.152/3047.2.55.153 to 47.2.55.15447.2.55.1552
23247.2.55.156/3047.2.55.157 to 47.2.55.15847.2.55.1592
23347.2.55.160/3047.2.55.161 to 47.2.55.16247.2.55.1632
23447.2.55.164/3047.2.55.165 to 47.2.55.16647.2.55.1672
23547.2.55.168/3047.2.55.169 to 47.2.55.17047.2.55.1712
23647.2.55.172/3047.2.55.173 to 47.2.55.17447.2.55.1752
23747.2.55.176/3047.2.55.177 to 47.2.55.17847.2.55.1792
23847.2.55.180/3047.2.55.181 to 47.2.55.18247.2.55.1832
23947.2.55.184/3047.2.55.185 to 47.2.55.18647.2.55.1872
24047.2.55.188/3047.2.55.189 to 47.2.55.19047.2.55.1912
24147.2.55.192/3047.2.55.193 to 47.2.55.19447.2.55.1952
24247.2.55.196/3047.2.55.197 to 47.2.55.19847.2.55.1992
24347.2.55.200/3047.2.55.201 to 47.2.55.20247.2.55.2032
24447.2.55.204/3047.2.55.205 to 47.2.55.20647.2.55.2072
24547.2.55.208/3047.2.55.209 to 47.2.55.21047.2.55.2112
24647.2.55.212/3047.2.55.213 to 47.2.55.21447.2.55.2152
24747.2.55.216/3047.2.55.217 to 47.2.55.21847.2.55.2192
24847.2.55.220/3047.2.55.221 to 47.2.55.22247.2.55.2232
24947.2.55.224/3047.2.55.225 to 47.2.55.22647.2.55.2272
25047.2.55.228/3047.2.55.229 to 47.2.55.23047.2.55.2312
25147.2.55.232/3047.2.55.233 to 47.2.55.23447.2.55.2352
25247.2.55.236/3047.2.55.237 to 47.2.55.23847.2.55.2392
25347.2.55.240/3047.2.55.241 to 47.2.55.24247.2.55.2432
25447.2.55.244/3047.2.55.245 to 47.2.55.24647.2.55.2472
25547.2.55.248/3047.2.55.249 to 47.2.55.25047.2.55.2512
25647.2.55.252/3047.2.55.253 to 47.2.55.25447.2.55.2552

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.