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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/27
/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 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.167.0.0/2747.167.0.1 to 47.167.0.3047.167.0.3130
247.167.0.32/2747.167.0.33 to 47.167.0.6247.167.0.6330
347.167.0.64/2747.167.0.65 to 47.167.0.9447.167.0.9530
447.167.0.96/2747.167.0.97 to 47.167.0.12647.167.0.12730
547.167.0.128/2747.167.0.129 to 47.167.0.15847.167.0.15930
647.167.0.160/2747.167.0.161 to 47.167.0.19047.167.0.19130
747.167.0.192/2747.167.0.193 to 47.167.0.22247.167.0.22330
847.167.0.224/2747.167.0.225 to 47.167.0.25447.167.0.25530
947.167.1.0/2747.167.1.1 to 47.167.1.3047.167.1.3130
1047.167.1.32/2747.167.1.33 to 47.167.1.6247.167.1.6330
1147.167.1.64/2747.167.1.65 to 47.167.1.9447.167.1.9530
1247.167.1.96/2747.167.1.97 to 47.167.1.12647.167.1.12730
1347.167.1.128/2747.167.1.129 to 47.167.1.15847.167.1.15930
1447.167.1.160/2747.167.1.161 to 47.167.1.19047.167.1.19130
1547.167.1.192/2747.167.1.193 to 47.167.1.22247.167.1.22330
1647.167.1.224/2747.167.1.225 to 47.167.1.25447.167.1.25530
1747.167.2.0/2747.167.2.1 to 47.167.2.3047.167.2.3130
1847.167.2.32/2747.167.2.33 to 47.167.2.6247.167.2.6330
1947.167.2.64/2747.167.2.65 to 47.167.2.9447.167.2.9530
2047.167.2.96/2747.167.2.97 to 47.167.2.12647.167.2.12730
2147.167.2.128/2747.167.2.129 to 47.167.2.15847.167.2.15930
2247.167.2.160/2747.167.2.161 to 47.167.2.19047.167.2.19130
2347.167.2.192/2747.167.2.193 to 47.167.2.22247.167.2.22330
2447.167.2.224/2747.167.2.225 to 47.167.2.25447.167.2.25530
2547.167.3.0/2747.167.3.1 to 47.167.3.3047.167.3.3130
2647.167.3.32/2747.167.3.33 to 47.167.3.6247.167.3.6330
2747.167.3.64/2747.167.3.65 to 47.167.3.9447.167.3.9530
2847.167.3.96/2747.167.3.97 to 47.167.3.12647.167.3.12730
2947.167.3.128/2747.167.3.129 to 47.167.3.15847.167.3.15930
3047.167.3.160/2747.167.3.161 to 47.167.3.19047.167.3.19130
3147.167.3.192/2747.167.3.193 to 47.167.3.22247.167.3.22330
3247.167.3.224/2747.167.3.225 to 47.167.3.25447.167.3.25530
3347.167.4.0/2747.167.4.1 to 47.167.4.3047.167.4.3130
3447.167.4.32/2747.167.4.33 to 47.167.4.6247.167.4.6330
3547.167.4.64/2747.167.4.65 to 47.167.4.9447.167.4.9530
3647.167.4.96/2747.167.4.97 to 47.167.4.12647.167.4.12730
3747.167.4.128/2747.167.4.129 to 47.167.4.15847.167.4.15930
3847.167.4.160/2747.167.4.161 to 47.167.4.19047.167.4.19130
3947.167.4.192/2747.167.4.193 to 47.167.4.22247.167.4.22330
4047.167.4.224/2747.167.4.225 to 47.167.4.25447.167.4.25530
4147.167.5.0/2747.167.5.1 to 47.167.5.3047.167.5.3130
4247.167.5.32/2747.167.5.33 to 47.167.5.6247.167.5.6330
4347.167.5.64/2747.167.5.65 to 47.167.5.9447.167.5.9530
4447.167.5.96/2747.167.5.97 to 47.167.5.12647.167.5.12730
4547.167.5.128/2747.167.5.129 to 47.167.5.15847.167.5.15930
4647.167.5.160/2747.167.5.161 to 47.167.5.19047.167.5.19130
4747.167.5.192/2747.167.5.193 to 47.167.5.22247.167.5.22330
4847.167.5.224/2747.167.5.225 to 47.167.5.25447.167.5.25530
4947.167.6.0/2747.167.6.1 to 47.167.6.3047.167.6.3130
5047.167.6.32/2747.167.6.33 to 47.167.6.6247.167.6.6330
5147.167.6.64/2747.167.6.65 to 47.167.6.9447.167.6.9530
5247.167.6.96/2747.167.6.97 to 47.167.6.12647.167.6.12730
5347.167.6.128/2747.167.6.129 to 47.167.6.15847.167.6.15930
5447.167.6.160/2747.167.6.161 to 47.167.6.19047.167.6.19130
5547.167.6.192/2747.167.6.193 to 47.167.6.22247.167.6.22330
5647.167.6.224/2747.167.6.225 to 47.167.6.25447.167.6.25530
5747.167.7.0/2747.167.7.1 to 47.167.7.3047.167.7.3130
5847.167.7.32/2747.167.7.33 to 47.167.7.6247.167.7.6330
5947.167.7.64/2747.167.7.65 to 47.167.7.9447.167.7.9530
6047.167.7.96/2747.167.7.97 to 47.167.7.12647.167.7.12730
6147.167.7.128/2747.167.7.129 to 47.167.7.15847.167.7.15930
6247.167.7.160/2747.167.7.161 to 47.167.7.19047.167.7.19130
6347.167.7.192/2747.167.7.193 to 47.167.7.22247.167.7.22330
6447.167.7.224/2747.167.7.225 to 47.167.7.25447.167.7.25530
6547.167.8.0/2747.167.8.1 to 47.167.8.3047.167.8.3130
6647.167.8.32/2747.167.8.33 to 47.167.8.6247.167.8.6330
6747.167.8.64/2747.167.8.65 to 47.167.8.9447.167.8.9530
6847.167.8.96/2747.167.8.97 to 47.167.8.12647.167.8.12730
6947.167.8.128/2747.167.8.129 to 47.167.8.15847.167.8.15930
7047.167.8.160/2747.167.8.161 to 47.167.8.19047.167.8.19130
7147.167.8.192/2747.167.8.193 to 47.167.8.22247.167.8.22330
7247.167.8.224/2747.167.8.225 to 47.167.8.25447.167.8.25530
7347.167.9.0/2747.167.9.1 to 47.167.9.3047.167.9.3130
7447.167.9.32/2747.167.9.33 to 47.167.9.6247.167.9.6330
7547.167.9.64/2747.167.9.65 to 47.167.9.9447.167.9.9530
7647.167.9.96/2747.167.9.97 to 47.167.9.12647.167.9.12730
7747.167.9.128/2747.167.9.129 to 47.167.9.15847.167.9.15930
7847.167.9.160/2747.167.9.161 to 47.167.9.19047.167.9.19130
7947.167.9.192/2747.167.9.193 to 47.167.9.22247.167.9.22330
8047.167.9.224/2747.167.9.225 to 47.167.9.25447.167.9.25530
8147.167.10.0/2747.167.10.1 to 47.167.10.3047.167.10.3130
8247.167.10.32/2747.167.10.33 to 47.167.10.6247.167.10.6330
8347.167.10.64/2747.167.10.65 to 47.167.10.9447.167.10.9530
8447.167.10.96/2747.167.10.97 to 47.167.10.12647.167.10.12730
8547.167.10.128/2747.167.10.129 to 47.167.10.15847.167.10.15930
8647.167.10.160/2747.167.10.161 to 47.167.10.19047.167.10.19130
8747.167.10.192/2747.167.10.193 to 47.167.10.22247.167.10.22330
8847.167.10.224/2747.167.10.225 to 47.167.10.25447.167.10.25530
8947.167.11.0/2747.167.11.1 to 47.167.11.3047.167.11.3130
9047.167.11.32/2747.167.11.33 to 47.167.11.6247.167.11.6330
9147.167.11.64/2747.167.11.65 to 47.167.11.9447.167.11.9530
9247.167.11.96/2747.167.11.97 to 47.167.11.12647.167.11.12730
9347.167.11.128/2747.167.11.129 to 47.167.11.15847.167.11.15930
9447.167.11.160/2747.167.11.161 to 47.167.11.19047.167.11.19130
9547.167.11.192/2747.167.11.193 to 47.167.11.22247.167.11.22330
9647.167.11.224/2747.167.11.225 to 47.167.11.25447.167.11.25530
9747.167.12.0/2747.167.12.1 to 47.167.12.3047.167.12.3130
9847.167.12.32/2747.167.12.33 to 47.167.12.6247.167.12.6330
9947.167.12.64/2747.167.12.65 to 47.167.12.9447.167.12.9530
10047.167.12.96/2747.167.12.97 to 47.167.12.12647.167.12.12730
10147.167.12.128/2747.167.12.129 to 47.167.12.15847.167.12.15930
10247.167.12.160/2747.167.12.161 to 47.167.12.19047.167.12.19130
10347.167.12.192/2747.167.12.193 to 47.167.12.22247.167.12.22330
10447.167.12.224/2747.167.12.225 to 47.167.12.25447.167.12.25530
10547.167.13.0/2747.167.13.1 to 47.167.13.3047.167.13.3130
10647.167.13.32/2747.167.13.33 to 47.167.13.6247.167.13.6330
10747.167.13.64/2747.167.13.65 to 47.167.13.9447.167.13.9530
10847.167.13.96/2747.167.13.97 to 47.167.13.12647.167.13.12730
10947.167.13.128/2747.167.13.129 to 47.167.13.15847.167.13.15930
11047.167.13.160/2747.167.13.161 to 47.167.13.19047.167.13.19130
11147.167.13.192/2747.167.13.193 to 47.167.13.22247.167.13.22330
11247.167.13.224/2747.167.13.225 to 47.167.13.25447.167.13.25530
11347.167.14.0/2747.167.14.1 to 47.167.14.3047.167.14.3130
11447.167.14.32/2747.167.14.33 to 47.167.14.6247.167.14.6330
11547.167.14.64/2747.167.14.65 to 47.167.14.9447.167.14.9530
11647.167.14.96/2747.167.14.97 to 47.167.14.12647.167.14.12730
11747.167.14.128/2747.167.14.129 to 47.167.14.15847.167.14.15930
11847.167.14.160/2747.167.14.161 to 47.167.14.19047.167.14.19130
11947.167.14.192/2747.167.14.193 to 47.167.14.22247.167.14.22330
12047.167.14.224/2747.167.14.225 to 47.167.14.25447.167.14.25530
12147.167.15.0/2747.167.15.1 to 47.167.15.3047.167.15.3130
12247.167.15.32/2747.167.15.33 to 47.167.15.6247.167.15.6330
12347.167.15.64/2747.167.15.65 to 47.167.15.9447.167.15.9530
12447.167.15.96/2747.167.15.97 to 47.167.15.12647.167.15.12730
12547.167.15.128/2747.167.15.129 to 47.167.15.15847.167.15.15930
12647.167.15.160/2747.167.15.161 to 47.167.15.19047.167.15.19130
12747.167.15.192/2747.167.15.193 to 47.167.15.22247.167.15.22330
12847.167.15.224/2747.167.15.225 to 47.167.15.25447.167.15.25530
12947.167.16.0/2747.167.16.1 to 47.167.16.3047.167.16.3130
13047.167.16.32/2747.167.16.33 to 47.167.16.6247.167.16.6330
13147.167.16.64/2747.167.16.65 to 47.167.16.9447.167.16.9530
13247.167.16.96/2747.167.16.97 to 47.167.16.12647.167.16.12730
13347.167.16.128/2747.167.16.129 to 47.167.16.15847.167.16.15930
13447.167.16.160/2747.167.16.161 to 47.167.16.19047.167.16.19130
13547.167.16.192/2747.167.16.193 to 47.167.16.22247.167.16.22330
13647.167.16.224/2747.167.16.225 to 47.167.16.25447.167.16.25530
13747.167.17.0/2747.167.17.1 to 47.167.17.3047.167.17.3130
13847.167.17.32/2747.167.17.33 to 47.167.17.6247.167.17.6330
13947.167.17.64/2747.167.17.65 to 47.167.17.9447.167.17.9530
14047.167.17.96/2747.167.17.97 to 47.167.17.12647.167.17.12730
14147.167.17.128/2747.167.17.129 to 47.167.17.15847.167.17.15930
14247.167.17.160/2747.167.17.161 to 47.167.17.19047.167.17.19130
14347.167.17.192/2747.167.17.193 to 47.167.17.22247.167.17.22330
14447.167.17.224/2747.167.17.225 to 47.167.17.25447.167.17.25530
14547.167.18.0/2747.167.18.1 to 47.167.18.3047.167.18.3130
14647.167.18.32/2747.167.18.33 to 47.167.18.6247.167.18.6330
14747.167.18.64/2747.167.18.65 to 47.167.18.9447.167.18.9530
14847.167.18.96/2747.167.18.97 to 47.167.18.12647.167.18.12730
14947.167.18.128/2747.167.18.129 to 47.167.18.15847.167.18.15930
15047.167.18.160/2747.167.18.161 to 47.167.18.19047.167.18.19130
15147.167.18.192/2747.167.18.193 to 47.167.18.22247.167.18.22330
15247.167.18.224/2747.167.18.225 to 47.167.18.25447.167.18.25530
15347.167.19.0/2747.167.19.1 to 47.167.19.3047.167.19.3130
15447.167.19.32/2747.167.19.33 to 47.167.19.6247.167.19.6330
15547.167.19.64/2747.167.19.65 to 47.167.19.9447.167.19.9530
15647.167.19.96/2747.167.19.97 to 47.167.19.12647.167.19.12730
15747.167.19.128/2747.167.19.129 to 47.167.19.15847.167.19.15930
15847.167.19.160/2747.167.19.161 to 47.167.19.19047.167.19.19130
15947.167.19.192/2747.167.19.193 to 47.167.19.22247.167.19.22330
16047.167.19.224/2747.167.19.225 to 47.167.19.25447.167.19.25530
16147.167.20.0/2747.167.20.1 to 47.167.20.3047.167.20.3130
16247.167.20.32/2747.167.20.33 to 47.167.20.6247.167.20.6330
16347.167.20.64/2747.167.20.65 to 47.167.20.9447.167.20.9530
16447.167.20.96/2747.167.20.97 to 47.167.20.12647.167.20.12730
16547.167.20.128/2747.167.20.129 to 47.167.20.15847.167.20.15930
16647.167.20.160/2747.167.20.161 to 47.167.20.19047.167.20.19130
16747.167.20.192/2747.167.20.193 to 47.167.20.22247.167.20.22330
16847.167.20.224/2747.167.20.225 to 47.167.20.25447.167.20.25530
16947.167.21.0/2747.167.21.1 to 47.167.21.3047.167.21.3130
17047.167.21.32/2747.167.21.33 to 47.167.21.6247.167.21.6330
17147.167.21.64/2747.167.21.65 to 47.167.21.9447.167.21.9530
17247.167.21.96/2747.167.21.97 to 47.167.21.12647.167.21.12730
17347.167.21.128/2747.167.21.129 to 47.167.21.15847.167.21.15930
17447.167.21.160/2747.167.21.161 to 47.167.21.19047.167.21.19130
17547.167.21.192/2747.167.21.193 to 47.167.21.22247.167.21.22330
17647.167.21.224/2747.167.21.225 to 47.167.21.25447.167.21.25530
17747.167.22.0/2747.167.22.1 to 47.167.22.3047.167.22.3130
17847.167.22.32/2747.167.22.33 to 47.167.22.6247.167.22.6330
17947.167.22.64/2747.167.22.65 to 47.167.22.9447.167.22.9530
18047.167.22.96/2747.167.22.97 to 47.167.22.12647.167.22.12730
18147.167.22.128/2747.167.22.129 to 47.167.22.15847.167.22.15930
18247.167.22.160/2747.167.22.161 to 47.167.22.19047.167.22.19130
18347.167.22.192/2747.167.22.193 to 47.167.22.22247.167.22.22330
18447.167.22.224/2747.167.22.225 to 47.167.22.25447.167.22.25530
18547.167.23.0/2747.167.23.1 to 47.167.23.3047.167.23.3130
18647.167.23.32/2747.167.23.33 to 47.167.23.6247.167.23.6330
18747.167.23.64/2747.167.23.65 to 47.167.23.9447.167.23.9530
18847.167.23.96/2747.167.23.97 to 47.167.23.12647.167.23.12730
18947.167.23.128/2747.167.23.129 to 47.167.23.15847.167.23.15930
19047.167.23.160/2747.167.23.161 to 47.167.23.19047.167.23.19130
19147.167.23.192/2747.167.23.193 to 47.167.23.22247.167.23.22330
19247.167.23.224/2747.167.23.225 to 47.167.23.25447.167.23.25530
19347.167.24.0/2747.167.24.1 to 47.167.24.3047.167.24.3130
19447.167.24.32/2747.167.24.33 to 47.167.24.6247.167.24.6330
19547.167.24.64/2747.167.24.65 to 47.167.24.9447.167.24.9530
19647.167.24.96/2747.167.24.97 to 47.167.24.12647.167.24.12730
19747.167.24.128/2747.167.24.129 to 47.167.24.15847.167.24.15930
19847.167.24.160/2747.167.24.161 to 47.167.24.19047.167.24.19130
19947.167.24.192/2747.167.24.193 to 47.167.24.22247.167.24.22330
20047.167.24.224/2747.167.24.225 to 47.167.24.25447.167.24.25530
20147.167.25.0/2747.167.25.1 to 47.167.25.3047.167.25.3130
20247.167.25.32/2747.167.25.33 to 47.167.25.6247.167.25.6330
20347.167.25.64/2747.167.25.65 to 47.167.25.9447.167.25.9530
20447.167.25.96/2747.167.25.97 to 47.167.25.12647.167.25.12730
20547.167.25.128/2747.167.25.129 to 47.167.25.15847.167.25.15930
20647.167.25.160/2747.167.25.161 to 47.167.25.19047.167.25.19130
20747.167.25.192/2747.167.25.193 to 47.167.25.22247.167.25.22330
20847.167.25.224/2747.167.25.225 to 47.167.25.25447.167.25.25530
20947.167.26.0/2747.167.26.1 to 47.167.26.3047.167.26.3130
21047.167.26.32/2747.167.26.33 to 47.167.26.6247.167.26.6330
21147.167.26.64/2747.167.26.65 to 47.167.26.9447.167.26.9530
21247.167.26.96/2747.167.26.97 to 47.167.26.12647.167.26.12730
21347.167.26.128/2747.167.26.129 to 47.167.26.15847.167.26.15930
21447.167.26.160/2747.167.26.161 to 47.167.26.19047.167.26.19130
21547.167.26.192/2747.167.26.193 to 47.167.26.22247.167.26.22330
21647.167.26.224/2747.167.26.225 to 47.167.26.25447.167.26.25530
21747.167.27.0/2747.167.27.1 to 47.167.27.3047.167.27.3130
21847.167.27.32/2747.167.27.33 to 47.167.27.6247.167.27.6330
21947.167.27.64/2747.167.27.65 to 47.167.27.9447.167.27.9530
22047.167.27.96/2747.167.27.97 to 47.167.27.12647.167.27.12730
22147.167.27.128/2747.167.27.129 to 47.167.27.15847.167.27.15930
22247.167.27.160/2747.167.27.161 to 47.167.27.19047.167.27.19130
22347.167.27.192/2747.167.27.193 to 47.167.27.22247.167.27.22330
22447.167.27.224/2747.167.27.225 to 47.167.27.25447.167.27.25530
22547.167.28.0/2747.167.28.1 to 47.167.28.3047.167.28.3130
22647.167.28.32/2747.167.28.33 to 47.167.28.6247.167.28.6330
22747.167.28.64/2747.167.28.65 to 47.167.28.9447.167.28.9530
22847.167.28.96/2747.167.28.97 to 47.167.28.12647.167.28.12730
22947.167.28.128/2747.167.28.129 to 47.167.28.15847.167.28.15930
23047.167.28.160/2747.167.28.161 to 47.167.28.19047.167.28.19130
23147.167.28.192/2747.167.28.193 to 47.167.28.22247.167.28.22330
23247.167.28.224/2747.167.28.225 to 47.167.28.25447.167.28.25530
23347.167.29.0/2747.167.29.1 to 47.167.29.3047.167.29.3130
23447.167.29.32/2747.167.29.33 to 47.167.29.6247.167.29.6330
23547.167.29.64/2747.167.29.65 to 47.167.29.9447.167.29.9530
23647.167.29.96/2747.167.29.97 to 47.167.29.12647.167.29.12730
23747.167.29.128/2747.167.29.129 to 47.167.29.15847.167.29.15930
23847.167.29.160/2747.167.29.161 to 47.167.29.19047.167.29.19130
23947.167.29.192/2747.167.29.193 to 47.167.29.22247.167.29.22330
24047.167.29.224/2747.167.29.225 to 47.167.29.25447.167.29.25530
24147.167.30.0/2747.167.30.1 to 47.167.30.3047.167.30.3130
24247.167.30.32/2747.167.30.33 to 47.167.30.6247.167.30.6330
24347.167.30.64/2747.167.30.65 to 47.167.30.9447.167.30.9530
24447.167.30.96/2747.167.30.97 to 47.167.30.12647.167.30.12730
24547.167.30.128/2747.167.30.129 to 47.167.30.15847.167.30.15930
24647.167.30.160/2747.167.30.161 to 47.167.30.19047.167.30.19130
24747.167.30.192/2747.167.30.193 to 47.167.30.22247.167.30.22330
24847.167.30.224/2747.167.30.225 to 47.167.30.25447.167.30.25530
24947.167.31.0/2747.167.31.1 to 47.167.31.3047.167.31.3130
25047.167.31.32/2747.167.31.33 to 47.167.31.6247.167.31.6330
25147.167.31.64/2747.167.31.65 to 47.167.31.9447.167.31.9530
25247.167.31.96/2747.167.31.97 to 47.167.31.12647.167.31.12730
25347.167.31.128/2747.167.31.129 to 47.167.31.15847.167.31.15930
25447.167.31.160/2747.167.31.161 to 47.167.31.19047.167.31.19130
25547.167.31.192/2747.167.31.193 to 47.167.31.22247.167.31.22330
25647.167.31.224/2747.167.31.225 to 47.167.31.25447.167.31.25530

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.