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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.

Network16.60.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
16.60.0.0
Broadcast address
16.60.255.255
First usable
16.60.0.1
Last usable
16.60.255.254
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 103C0000 · Integer 272367616 to 272433151
Reverse DNS zone
60.16.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00010000.00111100..00000000.0000000016.60.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00010000.00111100..00000000.0000000016.60.0.0
Broadcast00010000.00111100..11111111.1111111116.60.255.255
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)

16.60.0.0/16 makes 2,048 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
116.60.0.0/2716.60.0.1 to 16.60.0.3016.60.0.3130
216.60.0.32/2716.60.0.33 to 16.60.0.6216.60.0.6330
316.60.0.64/2716.60.0.65 to 16.60.0.9416.60.0.9530
416.60.0.96/2716.60.0.97 to 16.60.0.12616.60.0.12730
516.60.0.128/2716.60.0.129 to 16.60.0.15816.60.0.15930
616.60.0.160/2716.60.0.161 to 16.60.0.19016.60.0.19130
716.60.0.192/2716.60.0.193 to 16.60.0.22216.60.0.22330
816.60.0.224/2716.60.0.225 to 16.60.0.25416.60.0.25530
916.60.1.0/2716.60.1.1 to 16.60.1.3016.60.1.3130
1016.60.1.32/2716.60.1.33 to 16.60.1.6216.60.1.6330
1116.60.1.64/2716.60.1.65 to 16.60.1.9416.60.1.9530
1216.60.1.96/2716.60.1.97 to 16.60.1.12616.60.1.12730
1316.60.1.128/2716.60.1.129 to 16.60.1.15816.60.1.15930
1416.60.1.160/2716.60.1.161 to 16.60.1.19016.60.1.19130
1516.60.1.192/2716.60.1.193 to 16.60.1.22216.60.1.22330
1616.60.1.224/2716.60.1.225 to 16.60.1.25416.60.1.25530
1716.60.2.0/2716.60.2.1 to 16.60.2.3016.60.2.3130
1816.60.2.32/2716.60.2.33 to 16.60.2.6216.60.2.6330
1916.60.2.64/2716.60.2.65 to 16.60.2.9416.60.2.9530
2016.60.2.96/2716.60.2.97 to 16.60.2.12616.60.2.12730
2116.60.2.128/2716.60.2.129 to 16.60.2.15816.60.2.15930
2216.60.2.160/2716.60.2.161 to 16.60.2.19016.60.2.19130
2316.60.2.192/2716.60.2.193 to 16.60.2.22216.60.2.22330
2416.60.2.224/2716.60.2.225 to 16.60.2.25416.60.2.25530
2516.60.3.0/2716.60.3.1 to 16.60.3.3016.60.3.3130
2616.60.3.32/2716.60.3.33 to 16.60.3.6216.60.3.6330
2716.60.3.64/2716.60.3.65 to 16.60.3.9416.60.3.9530
2816.60.3.96/2716.60.3.97 to 16.60.3.12616.60.3.12730
2916.60.3.128/2716.60.3.129 to 16.60.3.15816.60.3.15930
3016.60.3.160/2716.60.3.161 to 16.60.3.19016.60.3.19130
3116.60.3.192/2716.60.3.193 to 16.60.3.22216.60.3.22330
3216.60.3.224/2716.60.3.225 to 16.60.3.25416.60.3.25530
3316.60.4.0/2716.60.4.1 to 16.60.4.3016.60.4.3130
3416.60.4.32/2716.60.4.33 to 16.60.4.6216.60.4.6330
3516.60.4.64/2716.60.4.65 to 16.60.4.9416.60.4.9530
3616.60.4.96/2716.60.4.97 to 16.60.4.12616.60.4.12730
3716.60.4.128/2716.60.4.129 to 16.60.4.15816.60.4.15930
3816.60.4.160/2716.60.4.161 to 16.60.4.19016.60.4.19130
3916.60.4.192/2716.60.4.193 to 16.60.4.22216.60.4.22330
4016.60.4.224/2716.60.4.225 to 16.60.4.25416.60.4.25530
4116.60.5.0/2716.60.5.1 to 16.60.5.3016.60.5.3130
4216.60.5.32/2716.60.5.33 to 16.60.5.6216.60.5.6330
4316.60.5.64/2716.60.5.65 to 16.60.5.9416.60.5.9530
4416.60.5.96/2716.60.5.97 to 16.60.5.12616.60.5.12730
4516.60.5.128/2716.60.5.129 to 16.60.5.15816.60.5.15930
4616.60.5.160/2716.60.5.161 to 16.60.5.19016.60.5.19130
4716.60.5.192/2716.60.5.193 to 16.60.5.22216.60.5.22330
4816.60.5.224/2716.60.5.225 to 16.60.5.25416.60.5.25530
4916.60.6.0/2716.60.6.1 to 16.60.6.3016.60.6.3130
5016.60.6.32/2716.60.6.33 to 16.60.6.6216.60.6.6330
5116.60.6.64/2716.60.6.65 to 16.60.6.9416.60.6.9530
5216.60.6.96/2716.60.6.97 to 16.60.6.12616.60.6.12730
5316.60.6.128/2716.60.6.129 to 16.60.6.15816.60.6.15930
5416.60.6.160/2716.60.6.161 to 16.60.6.19016.60.6.19130
5516.60.6.192/2716.60.6.193 to 16.60.6.22216.60.6.22330
5616.60.6.224/2716.60.6.225 to 16.60.6.25416.60.6.25530
5716.60.7.0/2716.60.7.1 to 16.60.7.3016.60.7.3130
5816.60.7.32/2716.60.7.33 to 16.60.7.6216.60.7.6330
5916.60.7.64/2716.60.7.65 to 16.60.7.9416.60.7.9530
6016.60.7.96/2716.60.7.97 to 16.60.7.12616.60.7.12730
6116.60.7.128/2716.60.7.129 to 16.60.7.15816.60.7.15930
6216.60.7.160/2716.60.7.161 to 16.60.7.19016.60.7.19130
6316.60.7.192/2716.60.7.193 to 16.60.7.22216.60.7.22330
6416.60.7.224/2716.60.7.225 to 16.60.7.25416.60.7.25530
6516.60.8.0/2716.60.8.1 to 16.60.8.3016.60.8.3130
6616.60.8.32/2716.60.8.33 to 16.60.8.6216.60.8.6330
6716.60.8.64/2716.60.8.65 to 16.60.8.9416.60.8.9530
6816.60.8.96/2716.60.8.97 to 16.60.8.12616.60.8.12730
6916.60.8.128/2716.60.8.129 to 16.60.8.15816.60.8.15930
7016.60.8.160/2716.60.8.161 to 16.60.8.19016.60.8.19130
7116.60.8.192/2716.60.8.193 to 16.60.8.22216.60.8.22330
7216.60.8.224/2716.60.8.225 to 16.60.8.25416.60.8.25530
7316.60.9.0/2716.60.9.1 to 16.60.9.3016.60.9.3130
7416.60.9.32/2716.60.9.33 to 16.60.9.6216.60.9.6330
7516.60.9.64/2716.60.9.65 to 16.60.9.9416.60.9.9530
7616.60.9.96/2716.60.9.97 to 16.60.9.12616.60.9.12730
7716.60.9.128/2716.60.9.129 to 16.60.9.15816.60.9.15930
7816.60.9.160/2716.60.9.161 to 16.60.9.19016.60.9.19130
7916.60.9.192/2716.60.9.193 to 16.60.9.22216.60.9.22330
8016.60.9.224/2716.60.9.225 to 16.60.9.25416.60.9.25530
8116.60.10.0/2716.60.10.1 to 16.60.10.3016.60.10.3130
8216.60.10.32/2716.60.10.33 to 16.60.10.6216.60.10.6330
8316.60.10.64/2716.60.10.65 to 16.60.10.9416.60.10.9530
8416.60.10.96/2716.60.10.97 to 16.60.10.12616.60.10.12730
8516.60.10.128/2716.60.10.129 to 16.60.10.15816.60.10.15930
8616.60.10.160/2716.60.10.161 to 16.60.10.19016.60.10.19130
8716.60.10.192/2716.60.10.193 to 16.60.10.22216.60.10.22330
8816.60.10.224/2716.60.10.225 to 16.60.10.25416.60.10.25530
8916.60.11.0/2716.60.11.1 to 16.60.11.3016.60.11.3130
9016.60.11.32/2716.60.11.33 to 16.60.11.6216.60.11.6330
9116.60.11.64/2716.60.11.65 to 16.60.11.9416.60.11.9530
9216.60.11.96/2716.60.11.97 to 16.60.11.12616.60.11.12730
9316.60.11.128/2716.60.11.129 to 16.60.11.15816.60.11.15930
9416.60.11.160/2716.60.11.161 to 16.60.11.19016.60.11.19130
9516.60.11.192/2716.60.11.193 to 16.60.11.22216.60.11.22330
9616.60.11.224/2716.60.11.225 to 16.60.11.25416.60.11.25530
9716.60.12.0/2716.60.12.1 to 16.60.12.3016.60.12.3130
9816.60.12.32/2716.60.12.33 to 16.60.12.6216.60.12.6330
9916.60.12.64/2716.60.12.65 to 16.60.12.9416.60.12.9530
10016.60.12.96/2716.60.12.97 to 16.60.12.12616.60.12.12730
10116.60.12.128/2716.60.12.129 to 16.60.12.15816.60.12.15930
10216.60.12.160/2716.60.12.161 to 16.60.12.19016.60.12.19130
10316.60.12.192/2716.60.12.193 to 16.60.12.22216.60.12.22330
10416.60.12.224/2716.60.12.225 to 16.60.12.25416.60.12.25530
10516.60.13.0/2716.60.13.1 to 16.60.13.3016.60.13.3130
10616.60.13.32/2716.60.13.33 to 16.60.13.6216.60.13.6330
10716.60.13.64/2716.60.13.65 to 16.60.13.9416.60.13.9530
10816.60.13.96/2716.60.13.97 to 16.60.13.12616.60.13.12730
10916.60.13.128/2716.60.13.129 to 16.60.13.15816.60.13.15930
11016.60.13.160/2716.60.13.161 to 16.60.13.19016.60.13.19130
11116.60.13.192/2716.60.13.193 to 16.60.13.22216.60.13.22330
11216.60.13.224/2716.60.13.225 to 16.60.13.25416.60.13.25530
11316.60.14.0/2716.60.14.1 to 16.60.14.3016.60.14.3130
11416.60.14.32/2716.60.14.33 to 16.60.14.6216.60.14.6330
11516.60.14.64/2716.60.14.65 to 16.60.14.9416.60.14.9530
11616.60.14.96/2716.60.14.97 to 16.60.14.12616.60.14.12730
11716.60.14.128/2716.60.14.129 to 16.60.14.15816.60.14.15930
11816.60.14.160/2716.60.14.161 to 16.60.14.19016.60.14.19130
11916.60.14.192/2716.60.14.193 to 16.60.14.22216.60.14.22330
12016.60.14.224/2716.60.14.225 to 16.60.14.25416.60.14.25530
12116.60.15.0/2716.60.15.1 to 16.60.15.3016.60.15.3130
12216.60.15.32/2716.60.15.33 to 16.60.15.6216.60.15.6330
12316.60.15.64/2716.60.15.65 to 16.60.15.9416.60.15.9530
12416.60.15.96/2716.60.15.97 to 16.60.15.12616.60.15.12730
12516.60.15.128/2716.60.15.129 to 16.60.15.15816.60.15.15930
12616.60.15.160/2716.60.15.161 to 16.60.15.19016.60.15.19130
12716.60.15.192/2716.60.15.193 to 16.60.15.22216.60.15.22330
12816.60.15.224/2716.60.15.225 to 16.60.15.25416.60.15.25530
12916.60.16.0/2716.60.16.1 to 16.60.16.3016.60.16.3130
13016.60.16.32/2716.60.16.33 to 16.60.16.6216.60.16.6330
13116.60.16.64/2716.60.16.65 to 16.60.16.9416.60.16.9530
13216.60.16.96/2716.60.16.97 to 16.60.16.12616.60.16.12730
13316.60.16.128/2716.60.16.129 to 16.60.16.15816.60.16.15930
13416.60.16.160/2716.60.16.161 to 16.60.16.19016.60.16.19130
13516.60.16.192/2716.60.16.193 to 16.60.16.22216.60.16.22330
13616.60.16.224/2716.60.16.225 to 16.60.16.25416.60.16.25530
13716.60.17.0/2716.60.17.1 to 16.60.17.3016.60.17.3130
13816.60.17.32/2716.60.17.33 to 16.60.17.6216.60.17.6330
13916.60.17.64/2716.60.17.65 to 16.60.17.9416.60.17.9530
14016.60.17.96/2716.60.17.97 to 16.60.17.12616.60.17.12730
14116.60.17.128/2716.60.17.129 to 16.60.17.15816.60.17.15930
14216.60.17.160/2716.60.17.161 to 16.60.17.19016.60.17.19130
14316.60.17.192/2716.60.17.193 to 16.60.17.22216.60.17.22330
14416.60.17.224/2716.60.17.225 to 16.60.17.25416.60.17.25530
14516.60.18.0/2716.60.18.1 to 16.60.18.3016.60.18.3130
14616.60.18.32/2716.60.18.33 to 16.60.18.6216.60.18.6330
14716.60.18.64/2716.60.18.65 to 16.60.18.9416.60.18.9530
14816.60.18.96/2716.60.18.97 to 16.60.18.12616.60.18.12730
14916.60.18.128/2716.60.18.129 to 16.60.18.15816.60.18.15930
15016.60.18.160/2716.60.18.161 to 16.60.18.19016.60.18.19130
15116.60.18.192/2716.60.18.193 to 16.60.18.22216.60.18.22330
15216.60.18.224/2716.60.18.225 to 16.60.18.25416.60.18.25530
15316.60.19.0/2716.60.19.1 to 16.60.19.3016.60.19.3130
15416.60.19.32/2716.60.19.33 to 16.60.19.6216.60.19.6330
15516.60.19.64/2716.60.19.65 to 16.60.19.9416.60.19.9530
15616.60.19.96/2716.60.19.97 to 16.60.19.12616.60.19.12730
15716.60.19.128/2716.60.19.129 to 16.60.19.15816.60.19.15930
15816.60.19.160/2716.60.19.161 to 16.60.19.19016.60.19.19130
15916.60.19.192/2716.60.19.193 to 16.60.19.22216.60.19.22330
16016.60.19.224/2716.60.19.225 to 16.60.19.25416.60.19.25530
16116.60.20.0/2716.60.20.1 to 16.60.20.3016.60.20.3130
16216.60.20.32/2716.60.20.33 to 16.60.20.6216.60.20.6330
16316.60.20.64/2716.60.20.65 to 16.60.20.9416.60.20.9530
16416.60.20.96/2716.60.20.97 to 16.60.20.12616.60.20.12730
16516.60.20.128/2716.60.20.129 to 16.60.20.15816.60.20.15930
16616.60.20.160/2716.60.20.161 to 16.60.20.19016.60.20.19130
16716.60.20.192/2716.60.20.193 to 16.60.20.22216.60.20.22330
16816.60.20.224/2716.60.20.225 to 16.60.20.25416.60.20.25530
16916.60.21.0/2716.60.21.1 to 16.60.21.3016.60.21.3130
17016.60.21.32/2716.60.21.33 to 16.60.21.6216.60.21.6330
17116.60.21.64/2716.60.21.65 to 16.60.21.9416.60.21.9530
17216.60.21.96/2716.60.21.97 to 16.60.21.12616.60.21.12730
17316.60.21.128/2716.60.21.129 to 16.60.21.15816.60.21.15930
17416.60.21.160/2716.60.21.161 to 16.60.21.19016.60.21.19130
17516.60.21.192/2716.60.21.193 to 16.60.21.22216.60.21.22330
17616.60.21.224/2716.60.21.225 to 16.60.21.25416.60.21.25530
17716.60.22.0/2716.60.22.1 to 16.60.22.3016.60.22.3130
17816.60.22.32/2716.60.22.33 to 16.60.22.6216.60.22.6330
17916.60.22.64/2716.60.22.65 to 16.60.22.9416.60.22.9530
18016.60.22.96/2716.60.22.97 to 16.60.22.12616.60.22.12730
18116.60.22.128/2716.60.22.129 to 16.60.22.15816.60.22.15930
18216.60.22.160/2716.60.22.161 to 16.60.22.19016.60.22.19130
18316.60.22.192/2716.60.22.193 to 16.60.22.22216.60.22.22330
18416.60.22.224/2716.60.22.225 to 16.60.22.25416.60.22.25530
18516.60.23.0/2716.60.23.1 to 16.60.23.3016.60.23.3130
18616.60.23.32/2716.60.23.33 to 16.60.23.6216.60.23.6330
18716.60.23.64/2716.60.23.65 to 16.60.23.9416.60.23.9530
18816.60.23.96/2716.60.23.97 to 16.60.23.12616.60.23.12730
18916.60.23.128/2716.60.23.129 to 16.60.23.15816.60.23.15930
19016.60.23.160/2716.60.23.161 to 16.60.23.19016.60.23.19130
19116.60.23.192/2716.60.23.193 to 16.60.23.22216.60.23.22330
19216.60.23.224/2716.60.23.225 to 16.60.23.25416.60.23.25530
19316.60.24.0/2716.60.24.1 to 16.60.24.3016.60.24.3130
19416.60.24.32/2716.60.24.33 to 16.60.24.6216.60.24.6330
19516.60.24.64/2716.60.24.65 to 16.60.24.9416.60.24.9530
19616.60.24.96/2716.60.24.97 to 16.60.24.12616.60.24.12730
19716.60.24.128/2716.60.24.129 to 16.60.24.15816.60.24.15930
19816.60.24.160/2716.60.24.161 to 16.60.24.19016.60.24.19130
19916.60.24.192/2716.60.24.193 to 16.60.24.22216.60.24.22330
20016.60.24.224/2716.60.24.225 to 16.60.24.25416.60.24.25530
20116.60.25.0/2716.60.25.1 to 16.60.25.3016.60.25.3130
20216.60.25.32/2716.60.25.33 to 16.60.25.6216.60.25.6330
20316.60.25.64/2716.60.25.65 to 16.60.25.9416.60.25.9530
20416.60.25.96/2716.60.25.97 to 16.60.25.12616.60.25.12730
20516.60.25.128/2716.60.25.129 to 16.60.25.15816.60.25.15930
20616.60.25.160/2716.60.25.161 to 16.60.25.19016.60.25.19130
20716.60.25.192/2716.60.25.193 to 16.60.25.22216.60.25.22330
20816.60.25.224/2716.60.25.225 to 16.60.25.25416.60.25.25530
20916.60.26.0/2716.60.26.1 to 16.60.26.3016.60.26.3130
21016.60.26.32/2716.60.26.33 to 16.60.26.6216.60.26.6330
21116.60.26.64/2716.60.26.65 to 16.60.26.9416.60.26.9530
21216.60.26.96/2716.60.26.97 to 16.60.26.12616.60.26.12730
21316.60.26.128/2716.60.26.129 to 16.60.26.15816.60.26.15930
21416.60.26.160/2716.60.26.161 to 16.60.26.19016.60.26.19130
21516.60.26.192/2716.60.26.193 to 16.60.26.22216.60.26.22330
21616.60.26.224/2716.60.26.225 to 16.60.26.25416.60.26.25530
21716.60.27.0/2716.60.27.1 to 16.60.27.3016.60.27.3130
21816.60.27.32/2716.60.27.33 to 16.60.27.6216.60.27.6330
21916.60.27.64/2716.60.27.65 to 16.60.27.9416.60.27.9530
22016.60.27.96/2716.60.27.97 to 16.60.27.12616.60.27.12730
22116.60.27.128/2716.60.27.129 to 16.60.27.15816.60.27.15930
22216.60.27.160/2716.60.27.161 to 16.60.27.19016.60.27.19130
22316.60.27.192/2716.60.27.193 to 16.60.27.22216.60.27.22330
22416.60.27.224/2716.60.27.225 to 16.60.27.25416.60.27.25530
22516.60.28.0/2716.60.28.1 to 16.60.28.3016.60.28.3130
22616.60.28.32/2716.60.28.33 to 16.60.28.6216.60.28.6330
22716.60.28.64/2716.60.28.65 to 16.60.28.9416.60.28.9530
22816.60.28.96/2716.60.28.97 to 16.60.28.12616.60.28.12730
22916.60.28.128/2716.60.28.129 to 16.60.28.15816.60.28.15930
23016.60.28.160/2716.60.28.161 to 16.60.28.19016.60.28.19130
23116.60.28.192/2716.60.28.193 to 16.60.28.22216.60.28.22330
23216.60.28.224/2716.60.28.225 to 16.60.28.25416.60.28.25530
23316.60.29.0/2716.60.29.1 to 16.60.29.3016.60.29.3130
23416.60.29.32/2716.60.29.33 to 16.60.29.6216.60.29.6330
23516.60.29.64/2716.60.29.65 to 16.60.29.9416.60.29.9530
23616.60.29.96/2716.60.29.97 to 16.60.29.12616.60.29.12730
23716.60.29.128/2716.60.29.129 to 16.60.29.15816.60.29.15930
23816.60.29.160/2716.60.29.161 to 16.60.29.19016.60.29.19130
23916.60.29.192/2716.60.29.193 to 16.60.29.22216.60.29.22330
24016.60.29.224/2716.60.29.225 to 16.60.29.25416.60.29.25530
24116.60.30.0/2716.60.30.1 to 16.60.30.3016.60.30.3130
24216.60.30.32/2716.60.30.33 to 16.60.30.6216.60.30.6330
24316.60.30.64/2716.60.30.65 to 16.60.30.9416.60.30.9530
24416.60.30.96/2716.60.30.97 to 16.60.30.12616.60.30.12730
24516.60.30.128/2716.60.30.129 to 16.60.30.15816.60.30.15930
24616.60.30.160/2716.60.30.161 to 16.60.30.19016.60.30.19130
24716.60.30.192/2716.60.30.193 to 16.60.30.22216.60.30.22330
24816.60.30.224/2716.60.30.225 to 16.60.30.25416.60.30.25530
24916.60.31.0/2716.60.31.1 to 16.60.31.3016.60.31.3130
25016.60.31.32/2716.60.31.33 to 16.60.31.6216.60.31.6330
25116.60.31.64/2716.60.31.65 to 16.60.31.9416.60.31.9530
25216.60.31.96/2716.60.31.97 to 16.60.31.12616.60.31.12730
25316.60.31.128/2716.60.31.129 to 16.60.31.15816.60.31.15930
25416.60.31.160/2716.60.31.161 to 16.60.31.19016.60.31.19130
25516.60.31.192/2716.60.31.193 to 16.60.31.22216.60.31.22330
25616.60.31.224/2716.60.31.225 to 16.60.31.25416.60.31.25530

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.