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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.

Network47.167.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
47.167.0.0
Broadcast address
47.167.255.255
First usable
47.167.0.1
Last usable
47.167.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 2FA70000 · Integer 799473664 to 799539199
Reverse DNS zone
167.47.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101111.10100111..00000000.0000000047.167.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00101111.10100111..00000000.0000000047.167.0.0
Broadcast00101111.10100111..11111111.1111111147.167.255.255
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

47.167.0.0/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.167.0.0/2847.167.0.1 to 47.167.0.1447.167.0.1514
247.167.0.16/2847.167.0.17 to 47.167.0.3047.167.0.3114
347.167.0.32/2847.167.0.33 to 47.167.0.4647.167.0.4714
447.167.0.48/2847.167.0.49 to 47.167.0.6247.167.0.6314
547.167.0.64/2847.167.0.65 to 47.167.0.7847.167.0.7914
647.167.0.80/2847.167.0.81 to 47.167.0.9447.167.0.9514
747.167.0.96/2847.167.0.97 to 47.167.0.11047.167.0.11114
847.167.0.112/2847.167.0.113 to 47.167.0.12647.167.0.12714
947.167.0.128/2847.167.0.129 to 47.167.0.14247.167.0.14314
1047.167.0.144/2847.167.0.145 to 47.167.0.15847.167.0.15914
1147.167.0.160/2847.167.0.161 to 47.167.0.17447.167.0.17514
1247.167.0.176/2847.167.0.177 to 47.167.0.19047.167.0.19114
1347.167.0.192/2847.167.0.193 to 47.167.0.20647.167.0.20714
1447.167.0.208/2847.167.0.209 to 47.167.0.22247.167.0.22314
1547.167.0.224/2847.167.0.225 to 47.167.0.23847.167.0.23914
1647.167.0.240/2847.167.0.241 to 47.167.0.25447.167.0.25514
1747.167.1.0/2847.167.1.1 to 47.167.1.1447.167.1.1514
1847.167.1.16/2847.167.1.17 to 47.167.1.3047.167.1.3114
1947.167.1.32/2847.167.1.33 to 47.167.1.4647.167.1.4714
2047.167.1.48/2847.167.1.49 to 47.167.1.6247.167.1.6314
2147.167.1.64/2847.167.1.65 to 47.167.1.7847.167.1.7914
2247.167.1.80/2847.167.1.81 to 47.167.1.9447.167.1.9514
2347.167.1.96/2847.167.1.97 to 47.167.1.11047.167.1.11114
2447.167.1.112/2847.167.1.113 to 47.167.1.12647.167.1.12714
2547.167.1.128/2847.167.1.129 to 47.167.1.14247.167.1.14314
2647.167.1.144/2847.167.1.145 to 47.167.1.15847.167.1.15914
2747.167.1.160/2847.167.1.161 to 47.167.1.17447.167.1.17514
2847.167.1.176/2847.167.1.177 to 47.167.1.19047.167.1.19114
2947.167.1.192/2847.167.1.193 to 47.167.1.20647.167.1.20714
3047.167.1.208/2847.167.1.209 to 47.167.1.22247.167.1.22314
3147.167.1.224/2847.167.1.225 to 47.167.1.23847.167.1.23914
3247.167.1.240/2847.167.1.241 to 47.167.1.25447.167.1.25514
3347.167.2.0/2847.167.2.1 to 47.167.2.1447.167.2.1514
3447.167.2.16/2847.167.2.17 to 47.167.2.3047.167.2.3114
3547.167.2.32/2847.167.2.33 to 47.167.2.4647.167.2.4714
3647.167.2.48/2847.167.2.49 to 47.167.2.6247.167.2.6314
3747.167.2.64/2847.167.2.65 to 47.167.2.7847.167.2.7914
3847.167.2.80/2847.167.2.81 to 47.167.2.9447.167.2.9514
3947.167.2.96/2847.167.2.97 to 47.167.2.11047.167.2.11114
4047.167.2.112/2847.167.2.113 to 47.167.2.12647.167.2.12714
4147.167.2.128/2847.167.2.129 to 47.167.2.14247.167.2.14314
4247.167.2.144/2847.167.2.145 to 47.167.2.15847.167.2.15914
4347.167.2.160/2847.167.2.161 to 47.167.2.17447.167.2.17514
4447.167.2.176/2847.167.2.177 to 47.167.2.19047.167.2.19114
4547.167.2.192/2847.167.2.193 to 47.167.2.20647.167.2.20714
4647.167.2.208/2847.167.2.209 to 47.167.2.22247.167.2.22314
4747.167.2.224/2847.167.2.225 to 47.167.2.23847.167.2.23914
4847.167.2.240/2847.167.2.241 to 47.167.2.25447.167.2.25514
4947.167.3.0/2847.167.3.1 to 47.167.3.1447.167.3.1514
5047.167.3.16/2847.167.3.17 to 47.167.3.3047.167.3.3114
5147.167.3.32/2847.167.3.33 to 47.167.3.4647.167.3.4714
5247.167.3.48/2847.167.3.49 to 47.167.3.6247.167.3.6314
5347.167.3.64/2847.167.3.65 to 47.167.3.7847.167.3.7914
5447.167.3.80/2847.167.3.81 to 47.167.3.9447.167.3.9514
5547.167.3.96/2847.167.3.97 to 47.167.3.11047.167.3.11114
5647.167.3.112/2847.167.3.113 to 47.167.3.12647.167.3.12714
5747.167.3.128/2847.167.3.129 to 47.167.3.14247.167.3.14314
5847.167.3.144/2847.167.3.145 to 47.167.3.15847.167.3.15914
5947.167.3.160/2847.167.3.161 to 47.167.3.17447.167.3.17514
6047.167.3.176/2847.167.3.177 to 47.167.3.19047.167.3.19114
6147.167.3.192/2847.167.3.193 to 47.167.3.20647.167.3.20714
6247.167.3.208/2847.167.3.209 to 47.167.3.22247.167.3.22314
6347.167.3.224/2847.167.3.225 to 47.167.3.23847.167.3.23914
6447.167.3.240/2847.167.3.241 to 47.167.3.25447.167.3.25514
6547.167.4.0/2847.167.4.1 to 47.167.4.1447.167.4.1514
6647.167.4.16/2847.167.4.17 to 47.167.4.3047.167.4.3114
6747.167.4.32/2847.167.4.33 to 47.167.4.4647.167.4.4714
6847.167.4.48/2847.167.4.49 to 47.167.4.6247.167.4.6314
6947.167.4.64/2847.167.4.65 to 47.167.4.7847.167.4.7914
7047.167.4.80/2847.167.4.81 to 47.167.4.9447.167.4.9514
7147.167.4.96/2847.167.4.97 to 47.167.4.11047.167.4.11114
7247.167.4.112/2847.167.4.113 to 47.167.4.12647.167.4.12714
7347.167.4.128/2847.167.4.129 to 47.167.4.14247.167.4.14314
7447.167.4.144/2847.167.4.145 to 47.167.4.15847.167.4.15914
7547.167.4.160/2847.167.4.161 to 47.167.4.17447.167.4.17514
7647.167.4.176/2847.167.4.177 to 47.167.4.19047.167.4.19114
7747.167.4.192/2847.167.4.193 to 47.167.4.20647.167.4.20714
7847.167.4.208/2847.167.4.209 to 47.167.4.22247.167.4.22314
7947.167.4.224/2847.167.4.225 to 47.167.4.23847.167.4.23914
8047.167.4.240/2847.167.4.241 to 47.167.4.25447.167.4.25514
8147.167.5.0/2847.167.5.1 to 47.167.5.1447.167.5.1514
8247.167.5.16/2847.167.5.17 to 47.167.5.3047.167.5.3114
8347.167.5.32/2847.167.5.33 to 47.167.5.4647.167.5.4714
8447.167.5.48/2847.167.5.49 to 47.167.5.6247.167.5.6314
8547.167.5.64/2847.167.5.65 to 47.167.5.7847.167.5.7914
8647.167.5.80/2847.167.5.81 to 47.167.5.9447.167.5.9514
8747.167.5.96/2847.167.5.97 to 47.167.5.11047.167.5.11114
8847.167.5.112/2847.167.5.113 to 47.167.5.12647.167.5.12714
8947.167.5.128/2847.167.5.129 to 47.167.5.14247.167.5.14314
9047.167.5.144/2847.167.5.145 to 47.167.5.15847.167.5.15914
9147.167.5.160/2847.167.5.161 to 47.167.5.17447.167.5.17514
9247.167.5.176/2847.167.5.177 to 47.167.5.19047.167.5.19114
9347.167.5.192/2847.167.5.193 to 47.167.5.20647.167.5.20714
9447.167.5.208/2847.167.5.209 to 47.167.5.22247.167.5.22314
9547.167.5.224/2847.167.5.225 to 47.167.5.23847.167.5.23914
9647.167.5.240/2847.167.5.241 to 47.167.5.25447.167.5.25514
9747.167.6.0/2847.167.6.1 to 47.167.6.1447.167.6.1514
9847.167.6.16/2847.167.6.17 to 47.167.6.3047.167.6.3114
9947.167.6.32/2847.167.6.33 to 47.167.6.4647.167.6.4714
10047.167.6.48/2847.167.6.49 to 47.167.6.6247.167.6.6314
10147.167.6.64/2847.167.6.65 to 47.167.6.7847.167.6.7914
10247.167.6.80/2847.167.6.81 to 47.167.6.9447.167.6.9514
10347.167.6.96/2847.167.6.97 to 47.167.6.11047.167.6.11114
10447.167.6.112/2847.167.6.113 to 47.167.6.12647.167.6.12714
10547.167.6.128/2847.167.6.129 to 47.167.6.14247.167.6.14314
10647.167.6.144/2847.167.6.145 to 47.167.6.15847.167.6.15914
10747.167.6.160/2847.167.6.161 to 47.167.6.17447.167.6.17514
10847.167.6.176/2847.167.6.177 to 47.167.6.19047.167.6.19114
10947.167.6.192/2847.167.6.193 to 47.167.6.20647.167.6.20714
11047.167.6.208/2847.167.6.209 to 47.167.6.22247.167.6.22314
11147.167.6.224/2847.167.6.225 to 47.167.6.23847.167.6.23914
11247.167.6.240/2847.167.6.241 to 47.167.6.25447.167.6.25514
11347.167.7.0/2847.167.7.1 to 47.167.7.1447.167.7.1514
11447.167.7.16/2847.167.7.17 to 47.167.7.3047.167.7.3114
11547.167.7.32/2847.167.7.33 to 47.167.7.4647.167.7.4714
11647.167.7.48/2847.167.7.49 to 47.167.7.6247.167.7.6314
11747.167.7.64/2847.167.7.65 to 47.167.7.7847.167.7.7914
11847.167.7.80/2847.167.7.81 to 47.167.7.9447.167.7.9514
11947.167.7.96/2847.167.7.97 to 47.167.7.11047.167.7.11114
12047.167.7.112/2847.167.7.113 to 47.167.7.12647.167.7.12714
12147.167.7.128/2847.167.7.129 to 47.167.7.14247.167.7.14314
12247.167.7.144/2847.167.7.145 to 47.167.7.15847.167.7.15914
12347.167.7.160/2847.167.7.161 to 47.167.7.17447.167.7.17514
12447.167.7.176/2847.167.7.177 to 47.167.7.19047.167.7.19114
12547.167.7.192/2847.167.7.193 to 47.167.7.20647.167.7.20714
12647.167.7.208/2847.167.7.209 to 47.167.7.22247.167.7.22314
12747.167.7.224/2847.167.7.225 to 47.167.7.23847.167.7.23914
12847.167.7.240/2847.167.7.241 to 47.167.7.25447.167.7.25514
12947.167.8.0/2847.167.8.1 to 47.167.8.1447.167.8.1514
13047.167.8.16/2847.167.8.17 to 47.167.8.3047.167.8.3114
13147.167.8.32/2847.167.8.33 to 47.167.8.4647.167.8.4714
13247.167.8.48/2847.167.8.49 to 47.167.8.6247.167.8.6314
13347.167.8.64/2847.167.8.65 to 47.167.8.7847.167.8.7914
13447.167.8.80/2847.167.8.81 to 47.167.8.9447.167.8.9514
13547.167.8.96/2847.167.8.97 to 47.167.8.11047.167.8.11114
13647.167.8.112/2847.167.8.113 to 47.167.8.12647.167.8.12714
13747.167.8.128/2847.167.8.129 to 47.167.8.14247.167.8.14314
13847.167.8.144/2847.167.8.145 to 47.167.8.15847.167.8.15914
13947.167.8.160/2847.167.8.161 to 47.167.8.17447.167.8.17514
14047.167.8.176/2847.167.8.177 to 47.167.8.19047.167.8.19114
14147.167.8.192/2847.167.8.193 to 47.167.8.20647.167.8.20714
14247.167.8.208/2847.167.8.209 to 47.167.8.22247.167.8.22314
14347.167.8.224/2847.167.8.225 to 47.167.8.23847.167.8.23914
14447.167.8.240/2847.167.8.241 to 47.167.8.25447.167.8.25514
14547.167.9.0/2847.167.9.1 to 47.167.9.1447.167.9.1514
14647.167.9.16/2847.167.9.17 to 47.167.9.3047.167.9.3114
14747.167.9.32/2847.167.9.33 to 47.167.9.4647.167.9.4714
14847.167.9.48/2847.167.9.49 to 47.167.9.6247.167.9.6314
14947.167.9.64/2847.167.9.65 to 47.167.9.7847.167.9.7914
15047.167.9.80/2847.167.9.81 to 47.167.9.9447.167.9.9514
15147.167.9.96/2847.167.9.97 to 47.167.9.11047.167.9.11114
15247.167.9.112/2847.167.9.113 to 47.167.9.12647.167.9.12714
15347.167.9.128/2847.167.9.129 to 47.167.9.14247.167.9.14314
15447.167.9.144/2847.167.9.145 to 47.167.9.15847.167.9.15914
15547.167.9.160/2847.167.9.161 to 47.167.9.17447.167.9.17514
15647.167.9.176/2847.167.9.177 to 47.167.9.19047.167.9.19114
15747.167.9.192/2847.167.9.193 to 47.167.9.20647.167.9.20714
15847.167.9.208/2847.167.9.209 to 47.167.9.22247.167.9.22314
15947.167.9.224/2847.167.9.225 to 47.167.9.23847.167.9.23914
16047.167.9.240/2847.167.9.241 to 47.167.9.25447.167.9.25514
16147.167.10.0/2847.167.10.1 to 47.167.10.1447.167.10.1514
16247.167.10.16/2847.167.10.17 to 47.167.10.3047.167.10.3114
16347.167.10.32/2847.167.10.33 to 47.167.10.4647.167.10.4714
16447.167.10.48/2847.167.10.49 to 47.167.10.6247.167.10.6314
16547.167.10.64/2847.167.10.65 to 47.167.10.7847.167.10.7914
16647.167.10.80/2847.167.10.81 to 47.167.10.9447.167.10.9514
16747.167.10.96/2847.167.10.97 to 47.167.10.11047.167.10.11114
16847.167.10.112/2847.167.10.113 to 47.167.10.12647.167.10.12714
16947.167.10.128/2847.167.10.129 to 47.167.10.14247.167.10.14314
17047.167.10.144/2847.167.10.145 to 47.167.10.15847.167.10.15914
17147.167.10.160/2847.167.10.161 to 47.167.10.17447.167.10.17514
17247.167.10.176/2847.167.10.177 to 47.167.10.19047.167.10.19114
17347.167.10.192/2847.167.10.193 to 47.167.10.20647.167.10.20714
17447.167.10.208/2847.167.10.209 to 47.167.10.22247.167.10.22314
17547.167.10.224/2847.167.10.225 to 47.167.10.23847.167.10.23914
17647.167.10.240/2847.167.10.241 to 47.167.10.25447.167.10.25514
17747.167.11.0/2847.167.11.1 to 47.167.11.1447.167.11.1514
17847.167.11.16/2847.167.11.17 to 47.167.11.3047.167.11.3114
17947.167.11.32/2847.167.11.33 to 47.167.11.4647.167.11.4714
18047.167.11.48/2847.167.11.49 to 47.167.11.6247.167.11.6314
18147.167.11.64/2847.167.11.65 to 47.167.11.7847.167.11.7914
18247.167.11.80/2847.167.11.81 to 47.167.11.9447.167.11.9514
18347.167.11.96/2847.167.11.97 to 47.167.11.11047.167.11.11114
18447.167.11.112/2847.167.11.113 to 47.167.11.12647.167.11.12714
18547.167.11.128/2847.167.11.129 to 47.167.11.14247.167.11.14314
18647.167.11.144/2847.167.11.145 to 47.167.11.15847.167.11.15914
18747.167.11.160/2847.167.11.161 to 47.167.11.17447.167.11.17514
18847.167.11.176/2847.167.11.177 to 47.167.11.19047.167.11.19114
18947.167.11.192/2847.167.11.193 to 47.167.11.20647.167.11.20714
19047.167.11.208/2847.167.11.209 to 47.167.11.22247.167.11.22314
19147.167.11.224/2847.167.11.225 to 47.167.11.23847.167.11.23914
19247.167.11.240/2847.167.11.241 to 47.167.11.25447.167.11.25514
19347.167.12.0/2847.167.12.1 to 47.167.12.1447.167.12.1514
19447.167.12.16/2847.167.12.17 to 47.167.12.3047.167.12.3114
19547.167.12.32/2847.167.12.33 to 47.167.12.4647.167.12.4714
19647.167.12.48/2847.167.12.49 to 47.167.12.6247.167.12.6314
19747.167.12.64/2847.167.12.65 to 47.167.12.7847.167.12.7914
19847.167.12.80/2847.167.12.81 to 47.167.12.9447.167.12.9514
19947.167.12.96/2847.167.12.97 to 47.167.12.11047.167.12.11114
20047.167.12.112/2847.167.12.113 to 47.167.12.12647.167.12.12714
20147.167.12.128/2847.167.12.129 to 47.167.12.14247.167.12.14314
20247.167.12.144/2847.167.12.145 to 47.167.12.15847.167.12.15914
20347.167.12.160/2847.167.12.161 to 47.167.12.17447.167.12.17514
20447.167.12.176/2847.167.12.177 to 47.167.12.19047.167.12.19114
20547.167.12.192/2847.167.12.193 to 47.167.12.20647.167.12.20714
20647.167.12.208/2847.167.12.209 to 47.167.12.22247.167.12.22314
20747.167.12.224/2847.167.12.225 to 47.167.12.23847.167.12.23914
20847.167.12.240/2847.167.12.241 to 47.167.12.25447.167.12.25514
20947.167.13.0/2847.167.13.1 to 47.167.13.1447.167.13.1514
21047.167.13.16/2847.167.13.17 to 47.167.13.3047.167.13.3114
21147.167.13.32/2847.167.13.33 to 47.167.13.4647.167.13.4714
21247.167.13.48/2847.167.13.49 to 47.167.13.6247.167.13.6314
21347.167.13.64/2847.167.13.65 to 47.167.13.7847.167.13.7914
21447.167.13.80/2847.167.13.81 to 47.167.13.9447.167.13.9514
21547.167.13.96/2847.167.13.97 to 47.167.13.11047.167.13.11114
21647.167.13.112/2847.167.13.113 to 47.167.13.12647.167.13.12714
21747.167.13.128/2847.167.13.129 to 47.167.13.14247.167.13.14314
21847.167.13.144/2847.167.13.145 to 47.167.13.15847.167.13.15914
21947.167.13.160/2847.167.13.161 to 47.167.13.17447.167.13.17514
22047.167.13.176/2847.167.13.177 to 47.167.13.19047.167.13.19114
22147.167.13.192/2847.167.13.193 to 47.167.13.20647.167.13.20714
22247.167.13.208/2847.167.13.209 to 47.167.13.22247.167.13.22314
22347.167.13.224/2847.167.13.225 to 47.167.13.23847.167.13.23914
22447.167.13.240/2847.167.13.241 to 47.167.13.25447.167.13.25514
22547.167.14.0/2847.167.14.1 to 47.167.14.1447.167.14.1514
22647.167.14.16/2847.167.14.17 to 47.167.14.3047.167.14.3114
22747.167.14.32/2847.167.14.33 to 47.167.14.4647.167.14.4714
22847.167.14.48/2847.167.14.49 to 47.167.14.6247.167.14.6314
22947.167.14.64/2847.167.14.65 to 47.167.14.7847.167.14.7914
23047.167.14.80/2847.167.14.81 to 47.167.14.9447.167.14.9514
23147.167.14.96/2847.167.14.97 to 47.167.14.11047.167.14.11114
23247.167.14.112/2847.167.14.113 to 47.167.14.12647.167.14.12714
23347.167.14.128/2847.167.14.129 to 47.167.14.14247.167.14.14314
23447.167.14.144/2847.167.14.145 to 47.167.14.15847.167.14.15914
23547.167.14.160/2847.167.14.161 to 47.167.14.17447.167.14.17514
23647.167.14.176/2847.167.14.177 to 47.167.14.19047.167.14.19114
23747.167.14.192/2847.167.14.193 to 47.167.14.20647.167.14.20714
23847.167.14.208/2847.167.14.209 to 47.167.14.22247.167.14.22314
23947.167.14.224/2847.167.14.225 to 47.167.14.23847.167.14.23914
24047.167.14.240/2847.167.14.241 to 47.167.14.25447.167.14.25514
24147.167.15.0/2847.167.15.1 to 47.167.15.1447.167.15.1514
24247.167.15.16/2847.167.15.17 to 47.167.15.3047.167.15.3114
24347.167.15.32/2847.167.15.33 to 47.167.15.4647.167.15.4714
24447.167.15.48/2847.167.15.49 to 47.167.15.6247.167.15.6314
24547.167.15.64/2847.167.15.65 to 47.167.15.7847.167.15.7914
24647.167.15.80/2847.167.15.81 to 47.167.15.9447.167.15.9514
24747.167.15.96/2847.167.15.97 to 47.167.15.11047.167.15.11114
24847.167.15.112/2847.167.15.113 to 47.167.15.12647.167.15.12714
24947.167.15.128/2847.167.15.129 to 47.167.15.14247.167.15.14314
25047.167.15.144/2847.167.15.145 to 47.167.15.15847.167.15.15914
25147.167.15.160/2847.167.15.161 to 47.167.15.17447.167.15.17514
25247.167.15.176/2847.167.15.177 to 47.167.15.19047.167.15.19114
25347.167.15.192/2847.167.15.193 to 47.167.15.20647.167.15.20714
25447.167.15.208/2847.167.15.209 to 47.167.15.22247.167.15.22314
25547.167.15.224/2847.167.15.225 to 47.167.15.23847.167.15.23914
25647.167.15.240/2847.167.15.241 to 47.167.15.25447.167.15.25514

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.