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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.

Network95.3.192.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
95.3.192.0
Broadcast address
95.3.223.255
First usable
95.3.192.1
Last usable
95.3.223.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 5F03C000 · Integer 1594081280 to 1594089471
Reverse DNS zones
192.3.95.in-addr.arpa
193.3.95.in-addr.arpa
194.3.95.in-addr.arpa
195.3.95.in-addr.arpa
196.3.95.in-addr.arpa
197.3.95.in-addr.arpa
198.3.95.in-addr.arpa
199.3.95.in-addr.arpa
200.3.95.in-addr.arpa
201.3.95.in-addr.arpa
202.3.95.in-addr.arpa
203.3.95.in-addr.arpa
204.3.95.in-addr.arpa
205.3.95.in-addr.arpa
206.3.95.in-addr.arpa
207.3.95.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011111.00000011.11000000.0000000095.3.192.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network01011111.00000011.11000000.0000000095.3.192.0
Broadcast01011111.00000011.11011111.1111111195.3.223.255
Split into smaller subnets/28
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

95.3.192.0/19 makes 512 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
195.3.192.0/2895.3.192.1 to 95.3.192.1495.3.192.1514
295.3.192.16/2895.3.192.17 to 95.3.192.3095.3.192.3114
395.3.192.32/2895.3.192.33 to 95.3.192.4695.3.192.4714
495.3.192.48/2895.3.192.49 to 95.3.192.6295.3.192.6314
595.3.192.64/2895.3.192.65 to 95.3.192.7895.3.192.7914
695.3.192.80/2895.3.192.81 to 95.3.192.9495.3.192.9514
795.3.192.96/2895.3.192.97 to 95.3.192.11095.3.192.11114
895.3.192.112/2895.3.192.113 to 95.3.192.12695.3.192.12714
995.3.192.128/2895.3.192.129 to 95.3.192.14295.3.192.14314
1095.3.192.144/2895.3.192.145 to 95.3.192.15895.3.192.15914
1195.3.192.160/2895.3.192.161 to 95.3.192.17495.3.192.17514
1295.3.192.176/2895.3.192.177 to 95.3.192.19095.3.192.19114
1395.3.192.192/2895.3.192.193 to 95.3.192.20695.3.192.20714
1495.3.192.208/2895.3.192.209 to 95.3.192.22295.3.192.22314
1595.3.192.224/2895.3.192.225 to 95.3.192.23895.3.192.23914
1695.3.192.240/2895.3.192.241 to 95.3.192.25495.3.192.25514
1795.3.193.0/2895.3.193.1 to 95.3.193.1495.3.193.1514
1895.3.193.16/2895.3.193.17 to 95.3.193.3095.3.193.3114
1995.3.193.32/2895.3.193.33 to 95.3.193.4695.3.193.4714
2095.3.193.48/2895.3.193.49 to 95.3.193.6295.3.193.6314
2195.3.193.64/2895.3.193.65 to 95.3.193.7895.3.193.7914
2295.3.193.80/2895.3.193.81 to 95.3.193.9495.3.193.9514
2395.3.193.96/2895.3.193.97 to 95.3.193.11095.3.193.11114
2495.3.193.112/2895.3.193.113 to 95.3.193.12695.3.193.12714
2595.3.193.128/2895.3.193.129 to 95.3.193.14295.3.193.14314
2695.3.193.144/2895.3.193.145 to 95.3.193.15895.3.193.15914
2795.3.193.160/2895.3.193.161 to 95.3.193.17495.3.193.17514
2895.3.193.176/2895.3.193.177 to 95.3.193.19095.3.193.19114
2995.3.193.192/2895.3.193.193 to 95.3.193.20695.3.193.20714
3095.3.193.208/2895.3.193.209 to 95.3.193.22295.3.193.22314
3195.3.193.224/2895.3.193.225 to 95.3.193.23895.3.193.23914
3295.3.193.240/2895.3.193.241 to 95.3.193.25495.3.193.25514
3395.3.194.0/2895.3.194.1 to 95.3.194.1495.3.194.1514
3495.3.194.16/2895.3.194.17 to 95.3.194.3095.3.194.3114
3595.3.194.32/2895.3.194.33 to 95.3.194.4695.3.194.4714
3695.3.194.48/2895.3.194.49 to 95.3.194.6295.3.194.6314
3795.3.194.64/2895.3.194.65 to 95.3.194.7895.3.194.7914
3895.3.194.80/2895.3.194.81 to 95.3.194.9495.3.194.9514
3995.3.194.96/2895.3.194.97 to 95.3.194.11095.3.194.11114
4095.3.194.112/2895.3.194.113 to 95.3.194.12695.3.194.12714
4195.3.194.128/2895.3.194.129 to 95.3.194.14295.3.194.14314
4295.3.194.144/2895.3.194.145 to 95.3.194.15895.3.194.15914
4395.3.194.160/2895.3.194.161 to 95.3.194.17495.3.194.17514
4495.3.194.176/2895.3.194.177 to 95.3.194.19095.3.194.19114
4595.3.194.192/2895.3.194.193 to 95.3.194.20695.3.194.20714
4695.3.194.208/2895.3.194.209 to 95.3.194.22295.3.194.22314
4795.3.194.224/2895.3.194.225 to 95.3.194.23895.3.194.23914
4895.3.194.240/2895.3.194.241 to 95.3.194.25495.3.194.25514
4995.3.195.0/2895.3.195.1 to 95.3.195.1495.3.195.1514
5095.3.195.16/2895.3.195.17 to 95.3.195.3095.3.195.3114
5195.3.195.32/2895.3.195.33 to 95.3.195.4695.3.195.4714
5295.3.195.48/2895.3.195.49 to 95.3.195.6295.3.195.6314
5395.3.195.64/2895.3.195.65 to 95.3.195.7895.3.195.7914
5495.3.195.80/2895.3.195.81 to 95.3.195.9495.3.195.9514
5595.3.195.96/2895.3.195.97 to 95.3.195.11095.3.195.11114
5695.3.195.112/2895.3.195.113 to 95.3.195.12695.3.195.12714
5795.3.195.128/2895.3.195.129 to 95.3.195.14295.3.195.14314
5895.3.195.144/2895.3.195.145 to 95.3.195.15895.3.195.15914
5995.3.195.160/2895.3.195.161 to 95.3.195.17495.3.195.17514
6095.3.195.176/2895.3.195.177 to 95.3.195.19095.3.195.19114
6195.3.195.192/2895.3.195.193 to 95.3.195.20695.3.195.20714
6295.3.195.208/2895.3.195.209 to 95.3.195.22295.3.195.22314
6395.3.195.224/2895.3.195.225 to 95.3.195.23895.3.195.23914
6495.3.195.240/2895.3.195.241 to 95.3.195.25495.3.195.25514
6595.3.196.0/2895.3.196.1 to 95.3.196.1495.3.196.1514
6695.3.196.16/2895.3.196.17 to 95.3.196.3095.3.196.3114
6795.3.196.32/2895.3.196.33 to 95.3.196.4695.3.196.4714
6895.3.196.48/2895.3.196.49 to 95.3.196.6295.3.196.6314
6995.3.196.64/2895.3.196.65 to 95.3.196.7895.3.196.7914
7095.3.196.80/2895.3.196.81 to 95.3.196.9495.3.196.9514
7195.3.196.96/2895.3.196.97 to 95.3.196.11095.3.196.11114
7295.3.196.112/2895.3.196.113 to 95.3.196.12695.3.196.12714
7395.3.196.128/2895.3.196.129 to 95.3.196.14295.3.196.14314
7495.3.196.144/2895.3.196.145 to 95.3.196.15895.3.196.15914
7595.3.196.160/2895.3.196.161 to 95.3.196.17495.3.196.17514
7695.3.196.176/2895.3.196.177 to 95.3.196.19095.3.196.19114
7795.3.196.192/2895.3.196.193 to 95.3.196.20695.3.196.20714
7895.3.196.208/2895.3.196.209 to 95.3.196.22295.3.196.22314
7995.3.196.224/2895.3.196.225 to 95.3.196.23895.3.196.23914
8095.3.196.240/2895.3.196.241 to 95.3.196.25495.3.196.25514
8195.3.197.0/2895.3.197.1 to 95.3.197.1495.3.197.1514
8295.3.197.16/2895.3.197.17 to 95.3.197.3095.3.197.3114
8395.3.197.32/2895.3.197.33 to 95.3.197.4695.3.197.4714
8495.3.197.48/2895.3.197.49 to 95.3.197.6295.3.197.6314
8595.3.197.64/2895.3.197.65 to 95.3.197.7895.3.197.7914
8695.3.197.80/2895.3.197.81 to 95.3.197.9495.3.197.9514
8795.3.197.96/2895.3.197.97 to 95.3.197.11095.3.197.11114
8895.3.197.112/2895.3.197.113 to 95.3.197.12695.3.197.12714
8995.3.197.128/2895.3.197.129 to 95.3.197.14295.3.197.14314
9095.3.197.144/2895.3.197.145 to 95.3.197.15895.3.197.15914
9195.3.197.160/2895.3.197.161 to 95.3.197.17495.3.197.17514
9295.3.197.176/2895.3.197.177 to 95.3.197.19095.3.197.19114
9395.3.197.192/2895.3.197.193 to 95.3.197.20695.3.197.20714
9495.3.197.208/2895.3.197.209 to 95.3.197.22295.3.197.22314
9595.3.197.224/2895.3.197.225 to 95.3.197.23895.3.197.23914
9695.3.197.240/2895.3.197.241 to 95.3.197.25495.3.197.25514
9795.3.198.0/2895.3.198.1 to 95.3.198.1495.3.198.1514
9895.3.198.16/2895.3.198.17 to 95.3.198.3095.3.198.3114
9995.3.198.32/2895.3.198.33 to 95.3.198.4695.3.198.4714
10095.3.198.48/2895.3.198.49 to 95.3.198.6295.3.198.6314
10195.3.198.64/2895.3.198.65 to 95.3.198.7895.3.198.7914
10295.3.198.80/2895.3.198.81 to 95.3.198.9495.3.198.9514
10395.3.198.96/2895.3.198.97 to 95.3.198.11095.3.198.11114
10495.3.198.112/2895.3.198.113 to 95.3.198.12695.3.198.12714
10595.3.198.128/2895.3.198.129 to 95.3.198.14295.3.198.14314
10695.3.198.144/2895.3.198.145 to 95.3.198.15895.3.198.15914
10795.3.198.160/2895.3.198.161 to 95.3.198.17495.3.198.17514
10895.3.198.176/2895.3.198.177 to 95.3.198.19095.3.198.19114
10995.3.198.192/2895.3.198.193 to 95.3.198.20695.3.198.20714
11095.3.198.208/2895.3.198.209 to 95.3.198.22295.3.198.22314
11195.3.198.224/2895.3.198.225 to 95.3.198.23895.3.198.23914
11295.3.198.240/2895.3.198.241 to 95.3.198.25495.3.198.25514
11395.3.199.0/2895.3.199.1 to 95.3.199.1495.3.199.1514
11495.3.199.16/2895.3.199.17 to 95.3.199.3095.3.199.3114
11595.3.199.32/2895.3.199.33 to 95.3.199.4695.3.199.4714
11695.3.199.48/2895.3.199.49 to 95.3.199.6295.3.199.6314
11795.3.199.64/2895.3.199.65 to 95.3.199.7895.3.199.7914
11895.3.199.80/2895.3.199.81 to 95.3.199.9495.3.199.9514
11995.3.199.96/2895.3.199.97 to 95.3.199.11095.3.199.11114
12095.3.199.112/2895.3.199.113 to 95.3.199.12695.3.199.12714
12195.3.199.128/2895.3.199.129 to 95.3.199.14295.3.199.14314
12295.3.199.144/2895.3.199.145 to 95.3.199.15895.3.199.15914
12395.3.199.160/2895.3.199.161 to 95.3.199.17495.3.199.17514
12495.3.199.176/2895.3.199.177 to 95.3.199.19095.3.199.19114
12595.3.199.192/2895.3.199.193 to 95.3.199.20695.3.199.20714
12695.3.199.208/2895.3.199.209 to 95.3.199.22295.3.199.22314
12795.3.199.224/2895.3.199.225 to 95.3.199.23895.3.199.23914
12895.3.199.240/2895.3.199.241 to 95.3.199.25495.3.199.25514
12995.3.200.0/2895.3.200.1 to 95.3.200.1495.3.200.1514
13095.3.200.16/2895.3.200.17 to 95.3.200.3095.3.200.3114
13195.3.200.32/2895.3.200.33 to 95.3.200.4695.3.200.4714
13295.3.200.48/2895.3.200.49 to 95.3.200.6295.3.200.6314
13395.3.200.64/2895.3.200.65 to 95.3.200.7895.3.200.7914
13495.3.200.80/2895.3.200.81 to 95.3.200.9495.3.200.9514
13595.3.200.96/2895.3.200.97 to 95.3.200.11095.3.200.11114
13695.3.200.112/2895.3.200.113 to 95.3.200.12695.3.200.12714
13795.3.200.128/2895.3.200.129 to 95.3.200.14295.3.200.14314
13895.3.200.144/2895.3.200.145 to 95.3.200.15895.3.200.15914
13995.3.200.160/2895.3.200.161 to 95.3.200.17495.3.200.17514
14095.3.200.176/2895.3.200.177 to 95.3.200.19095.3.200.19114
14195.3.200.192/2895.3.200.193 to 95.3.200.20695.3.200.20714
14295.3.200.208/2895.3.200.209 to 95.3.200.22295.3.200.22314
14395.3.200.224/2895.3.200.225 to 95.3.200.23895.3.200.23914
14495.3.200.240/2895.3.200.241 to 95.3.200.25495.3.200.25514
14595.3.201.0/2895.3.201.1 to 95.3.201.1495.3.201.1514
14695.3.201.16/2895.3.201.17 to 95.3.201.3095.3.201.3114
14795.3.201.32/2895.3.201.33 to 95.3.201.4695.3.201.4714
14895.3.201.48/2895.3.201.49 to 95.3.201.6295.3.201.6314
14995.3.201.64/2895.3.201.65 to 95.3.201.7895.3.201.7914
15095.3.201.80/2895.3.201.81 to 95.3.201.9495.3.201.9514
15195.3.201.96/2895.3.201.97 to 95.3.201.11095.3.201.11114
15295.3.201.112/2895.3.201.113 to 95.3.201.12695.3.201.12714
15395.3.201.128/2895.3.201.129 to 95.3.201.14295.3.201.14314
15495.3.201.144/2895.3.201.145 to 95.3.201.15895.3.201.15914
15595.3.201.160/2895.3.201.161 to 95.3.201.17495.3.201.17514
15695.3.201.176/2895.3.201.177 to 95.3.201.19095.3.201.19114
15795.3.201.192/2895.3.201.193 to 95.3.201.20695.3.201.20714
15895.3.201.208/2895.3.201.209 to 95.3.201.22295.3.201.22314
15995.3.201.224/2895.3.201.225 to 95.3.201.23895.3.201.23914
16095.3.201.240/2895.3.201.241 to 95.3.201.25495.3.201.25514
16195.3.202.0/2895.3.202.1 to 95.3.202.1495.3.202.1514
16295.3.202.16/2895.3.202.17 to 95.3.202.3095.3.202.3114
16395.3.202.32/2895.3.202.33 to 95.3.202.4695.3.202.4714
16495.3.202.48/2895.3.202.49 to 95.3.202.6295.3.202.6314
16595.3.202.64/2895.3.202.65 to 95.3.202.7895.3.202.7914
16695.3.202.80/2895.3.202.81 to 95.3.202.9495.3.202.9514
16795.3.202.96/2895.3.202.97 to 95.3.202.11095.3.202.11114
16895.3.202.112/2895.3.202.113 to 95.3.202.12695.3.202.12714
16995.3.202.128/2895.3.202.129 to 95.3.202.14295.3.202.14314
17095.3.202.144/2895.3.202.145 to 95.3.202.15895.3.202.15914
17195.3.202.160/2895.3.202.161 to 95.3.202.17495.3.202.17514
17295.3.202.176/2895.3.202.177 to 95.3.202.19095.3.202.19114
17395.3.202.192/2895.3.202.193 to 95.3.202.20695.3.202.20714
17495.3.202.208/2895.3.202.209 to 95.3.202.22295.3.202.22314
17595.3.202.224/2895.3.202.225 to 95.3.202.23895.3.202.23914
17695.3.202.240/2895.3.202.241 to 95.3.202.25495.3.202.25514
17795.3.203.0/2895.3.203.1 to 95.3.203.1495.3.203.1514
17895.3.203.16/2895.3.203.17 to 95.3.203.3095.3.203.3114
17995.3.203.32/2895.3.203.33 to 95.3.203.4695.3.203.4714
18095.3.203.48/2895.3.203.49 to 95.3.203.6295.3.203.6314
18195.3.203.64/2895.3.203.65 to 95.3.203.7895.3.203.7914
18295.3.203.80/2895.3.203.81 to 95.3.203.9495.3.203.9514
18395.3.203.96/2895.3.203.97 to 95.3.203.11095.3.203.11114
18495.3.203.112/2895.3.203.113 to 95.3.203.12695.3.203.12714
18595.3.203.128/2895.3.203.129 to 95.3.203.14295.3.203.14314
18695.3.203.144/2895.3.203.145 to 95.3.203.15895.3.203.15914
18795.3.203.160/2895.3.203.161 to 95.3.203.17495.3.203.17514
18895.3.203.176/2895.3.203.177 to 95.3.203.19095.3.203.19114
18995.3.203.192/2895.3.203.193 to 95.3.203.20695.3.203.20714
19095.3.203.208/2895.3.203.209 to 95.3.203.22295.3.203.22314
19195.3.203.224/2895.3.203.225 to 95.3.203.23895.3.203.23914
19295.3.203.240/2895.3.203.241 to 95.3.203.25495.3.203.25514
19395.3.204.0/2895.3.204.1 to 95.3.204.1495.3.204.1514
19495.3.204.16/2895.3.204.17 to 95.3.204.3095.3.204.3114
19595.3.204.32/2895.3.204.33 to 95.3.204.4695.3.204.4714
19695.3.204.48/2895.3.204.49 to 95.3.204.6295.3.204.6314
19795.3.204.64/2895.3.204.65 to 95.3.204.7895.3.204.7914
19895.3.204.80/2895.3.204.81 to 95.3.204.9495.3.204.9514
19995.3.204.96/2895.3.204.97 to 95.3.204.11095.3.204.11114
20095.3.204.112/2895.3.204.113 to 95.3.204.12695.3.204.12714
20195.3.204.128/2895.3.204.129 to 95.3.204.14295.3.204.14314
20295.3.204.144/2895.3.204.145 to 95.3.204.15895.3.204.15914
20395.3.204.160/2895.3.204.161 to 95.3.204.17495.3.204.17514
20495.3.204.176/2895.3.204.177 to 95.3.204.19095.3.204.19114
20595.3.204.192/2895.3.204.193 to 95.3.204.20695.3.204.20714
20695.3.204.208/2895.3.204.209 to 95.3.204.22295.3.204.22314
20795.3.204.224/2895.3.204.225 to 95.3.204.23895.3.204.23914
20895.3.204.240/2895.3.204.241 to 95.3.204.25495.3.204.25514
20995.3.205.0/2895.3.205.1 to 95.3.205.1495.3.205.1514
21095.3.205.16/2895.3.205.17 to 95.3.205.3095.3.205.3114
21195.3.205.32/2895.3.205.33 to 95.3.205.4695.3.205.4714
21295.3.205.48/2895.3.205.49 to 95.3.205.6295.3.205.6314
21395.3.205.64/2895.3.205.65 to 95.3.205.7895.3.205.7914
21495.3.205.80/2895.3.205.81 to 95.3.205.9495.3.205.9514
21595.3.205.96/2895.3.205.97 to 95.3.205.11095.3.205.11114
21695.3.205.112/2895.3.205.113 to 95.3.205.12695.3.205.12714
21795.3.205.128/2895.3.205.129 to 95.3.205.14295.3.205.14314
21895.3.205.144/2895.3.205.145 to 95.3.205.15895.3.205.15914
21995.3.205.160/2895.3.205.161 to 95.3.205.17495.3.205.17514
22095.3.205.176/2895.3.205.177 to 95.3.205.19095.3.205.19114
22195.3.205.192/2895.3.205.193 to 95.3.205.20695.3.205.20714
22295.3.205.208/2895.3.205.209 to 95.3.205.22295.3.205.22314
22395.3.205.224/2895.3.205.225 to 95.3.205.23895.3.205.23914
22495.3.205.240/2895.3.205.241 to 95.3.205.25495.3.205.25514
22595.3.206.0/2895.3.206.1 to 95.3.206.1495.3.206.1514
22695.3.206.16/2895.3.206.17 to 95.3.206.3095.3.206.3114
22795.3.206.32/2895.3.206.33 to 95.3.206.4695.3.206.4714
22895.3.206.48/2895.3.206.49 to 95.3.206.6295.3.206.6314
22995.3.206.64/2895.3.206.65 to 95.3.206.7895.3.206.7914
23095.3.206.80/2895.3.206.81 to 95.3.206.9495.3.206.9514
23195.3.206.96/2895.3.206.97 to 95.3.206.11095.3.206.11114
23295.3.206.112/2895.3.206.113 to 95.3.206.12695.3.206.12714
23395.3.206.128/2895.3.206.129 to 95.3.206.14295.3.206.14314
23495.3.206.144/2895.3.206.145 to 95.3.206.15895.3.206.15914
23595.3.206.160/2895.3.206.161 to 95.3.206.17495.3.206.17514
23695.3.206.176/2895.3.206.177 to 95.3.206.19095.3.206.19114
23795.3.206.192/2895.3.206.193 to 95.3.206.20695.3.206.20714
23895.3.206.208/2895.3.206.209 to 95.3.206.22295.3.206.22314
23995.3.206.224/2895.3.206.225 to 95.3.206.23895.3.206.23914
24095.3.206.240/2895.3.206.241 to 95.3.206.25495.3.206.25514
24195.3.207.0/2895.3.207.1 to 95.3.207.1495.3.207.1514
24295.3.207.16/2895.3.207.17 to 95.3.207.3095.3.207.3114
24395.3.207.32/2895.3.207.33 to 95.3.207.4695.3.207.4714
24495.3.207.48/2895.3.207.49 to 95.3.207.6295.3.207.6314
24595.3.207.64/2895.3.207.65 to 95.3.207.7895.3.207.7914
24695.3.207.80/2895.3.207.81 to 95.3.207.9495.3.207.9514
24795.3.207.96/2895.3.207.97 to 95.3.207.11095.3.207.11114
24895.3.207.112/2895.3.207.113 to 95.3.207.12695.3.207.12714
24995.3.207.128/2895.3.207.129 to 95.3.207.14295.3.207.14314
25095.3.207.144/2895.3.207.145 to 95.3.207.15895.3.207.15914
25195.3.207.160/2895.3.207.161 to 95.3.207.17495.3.207.17514
25295.3.207.176/2895.3.207.177 to 95.3.207.19095.3.207.19114
25395.3.207.192/2895.3.207.193 to 95.3.207.20695.3.207.20714
25495.3.207.208/2895.3.207.209 to 95.3.207.22295.3.207.22314
25595.3.207.224/2895.3.207.225 to 95.3.207.23895.3.207.23914
25695.3.207.240/2895.3.207.241 to 95.3.207.25495.3.207.25514

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.