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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.

Network27.224.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
27.224.0.0
Broadcast address
27.255.255.255
First usable
27.224.0.1
Last usable
27.255.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
A (default /8)
As numbers
Hex 1BE00000 · Integer 467664896 to 469762047
Reverse DNS zones
224.27.in-addr.arpa
225.27.in-addr.arpa
226.27.in-addr.arpa
227.27.in-addr.arpa
228.27.in-addr.arpa
229.27.in-addr.arpa
230.27.in-addr.arpa
231.27.in-addr.arpa
232.27.in-addr.arpa
233.27.in-addr.arpa
234.27.in-addr.arpa
235.27.in-addr.arpa
236.27.in-addr.arpa
237.27.in-addr.arpa
238.27.in-addr.arpa
239.27.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00011011.11100000.00000000.0000000027.224.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network00011011.11100000.00000000.0000000027.224.0.0
Broadcast00011011.11111111.11111111.1111111127.255.255.255
Split into smaller subnets/19
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

27.224.0.0/11 makes 256 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
127.224.0.0/1927.224.0.1 to 27.224.31.25427.224.31.2558,190
227.224.32.0/1927.224.32.1 to 27.224.63.25427.224.63.2558,190
327.224.64.0/1927.224.64.1 to 27.224.95.25427.224.95.2558,190
427.224.96.0/1927.224.96.1 to 27.224.127.25427.224.127.2558,190
527.224.128.0/1927.224.128.1 to 27.224.159.25427.224.159.2558,190
627.224.160.0/1927.224.160.1 to 27.224.191.25427.224.191.2558,190
727.224.192.0/1927.224.192.1 to 27.224.223.25427.224.223.2558,190
827.224.224.0/1927.224.224.1 to 27.224.255.25427.224.255.2558,190
927.225.0.0/1927.225.0.1 to 27.225.31.25427.225.31.2558,190
1027.225.32.0/1927.225.32.1 to 27.225.63.25427.225.63.2558,190
1127.225.64.0/1927.225.64.1 to 27.225.95.25427.225.95.2558,190
1227.225.96.0/1927.225.96.1 to 27.225.127.25427.225.127.2558,190
1327.225.128.0/1927.225.128.1 to 27.225.159.25427.225.159.2558,190
1427.225.160.0/1927.225.160.1 to 27.225.191.25427.225.191.2558,190
1527.225.192.0/1927.225.192.1 to 27.225.223.25427.225.223.2558,190
1627.225.224.0/1927.225.224.1 to 27.225.255.25427.225.255.2558,190
1727.226.0.0/1927.226.0.1 to 27.226.31.25427.226.31.2558,190
1827.226.32.0/1927.226.32.1 to 27.226.63.25427.226.63.2558,190
1927.226.64.0/1927.226.64.1 to 27.226.95.25427.226.95.2558,190
2027.226.96.0/1927.226.96.1 to 27.226.127.25427.226.127.2558,190
2127.226.128.0/1927.226.128.1 to 27.226.159.25427.226.159.2558,190
2227.226.160.0/1927.226.160.1 to 27.226.191.25427.226.191.2558,190
2327.226.192.0/1927.226.192.1 to 27.226.223.25427.226.223.2558,190
2427.226.224.0/1927.226.224.1 to 27.226.255.25427.226.255.2558,190
2527.227.0.0/1927.227.0.1 to 27.227.31.25427.227.31.2558,190
2627.227.32.0/1927.227.32.1 to 27.227.63.25427.227.63.2558,190
2727.227.64.0/1927.227.64.1 to 27.227.95.25427.227.95.2558,190
2827.227.96.0/1927.227.96.1 to 27.227.127.25427.227.127.2558,190
2927.227.128.0/1927.227.128.1 to 27.227.159.25427.227.159.2558,190
3027.227.160.0/1927.227.160.1 to 27.227.191.25427.227.191.2558,190
3127.227.192.0/1927.227.192.1 to 27.227.223.25427.227.223.2558,190
3227.227.224.0/1927.227.224.1 to 27.227.255.25427.227.255.2558,190
3327.228.0.0/1927.228.0.1 to 27.228.31.25427.228.31.2558,190
3427.228.32.0/1927.228.32.1 to 27.228.63.25427.228.63.2558,190
3527.228.64.0/1927.228.64.1 to 27.228.95.25427.228.95.2558,190
3627.228.96.0/1927.228.96.1 to 27.228.127.25427.228.127.2558,190
3727.228.128.0/1927.228.128.1 to 27.228.159.25427.228.159.2558,190
3827.228.160.0/1927.228.160.1 to 27.228.191.25427.228.191.2558,190
3927.228.192.0/1927.228.192.1 to 27.228.223.25427.228.223.2558,190
4027.228.224.0/1927.228.224.1 to 27.228.255.25427.228.255.2558,190
4127.229.0.0/1927.229.0.1 to 27.229.31.25427.229.31.2558,190
4227.229.32.0/1927.229.32.1 to 27.229.63.25427.229.63.2558,190
4327.229.64.0/1927.229.64.1 to 27.229.95.25427.229.95.2558,190
4427.229.96.0/1927.229.96.1 to 27.229.127.25427.229.127.2558,190
4527.229.128.0/1927.229.128.1 to 27.229.159.25427.229.159.2558,190
4627.229.160.0/1927.229.160.1 to 27.229.191.25427.229.191.2558,190
4727.229.192.0/1927.229.192.1 to 27.229.223.25427.229.223.2558,190
4827.229.224.0/1927.229.224.1 to 27.229.255.25427.229.255.2558,190
4927.230.0.0/1927.230.0.1 to 27.230.31.25427.230.31.2558,190
5027.230.32.0/1927.230.32.1 to 27.230.63.25427.230.63.2558,190
5127.230.64.0/1927.230.64.1 to 27.230.95.25427.230.95.2558,190
5227.230.96.0/1927.230.96.1 to 27.230.127.25427.230.127.2558,190
5327.230.128.0/1927.230.128.1 to 27.230.159.25427.230.159.2558,190
5427.230.160.0/1927.230.160.1 to 27.230.191.25427.230.191.2558,190
5527.230.192.0/1927.230.192.1 to 27.230.223.25427.230.223.2558,190
5627.230.224.0/1927.230.224.1 to 27.230.255.25427.230.255.2558,190
5727.231.0.0/1927.231.0.1 to 27.231.31.25427.231.31.2558,190
5827.231.32.0/1927.231.32.1 to 27.231.63.25427.231.63.2558,190
5927.231.64.0/1927.231.64.1 to 27.231.95.25427.231.95.2558,190
6027.231.96.0/1927.231.96.1 to 27.231.127.25427.231.127.2558,190
6127.231.128.0/1927.231.128.1 to 27.231.159.25427.231.159.2558,190
6227.231.160.0/1927.231.160.1 to 27.231.191.25427.231.191.2558,190
6327.231.192.0/1927.231.192.1 to 27.231.223.25427.231.223.2558,190
6427.231.224.0/1927.231.224.1 to 27.231.255.25427.231.255.2558,190
6527.232.0.0/1927.232.0.1 to 27.232.31.25427.232.31.2558,190
6627.232.32.0/1927.232.32.1 to 27.232.63.25427.232.63.2558,190
6727.232.64.0/1927.232.64.1 to 27.232.95.25427.232.95.2558,190
6827.232.96.0/1927.232.96.1 to 27.232.127.25427.232.127.2558,190
6927.232.128.0/1927.232.128.1 to 27.232.159.25427.232.159.2558,190
7027.232.160.0/1927.232.160.1 to 27.232.191.25427.232.191.2558,190
7127.232.192.0/1927.232.192.1 to 27.232.223.25427.232.223.2558,190
7227.232.224.0/1927.232.224.1 to 27.232.255.25427.232.255.2558,190
7327.233.0.0/1927.233.0.1 to 27.233.31.25427.233.31.2558,190
7427.233.32.0/1927.233.32.1 to 27.233.63.25427.233.63.2558,190
7527.233.64.0/1927.233.64.1 to 27.233.95.25427.233.95.2558,190
7627.233.96.0/1927.233.96.1 to 27.233.127.25427.233.127.2558,190
7727.233.128.0/1927.233.128.1 to 27.233.159.25427.233.159.2558,190
7827.233.160.0/1927.233.160.1 to 27.233.191.25427.233.191.2558,190
7927.233.192.0/1927.233.192.1 to 27.233.223.25427.233.223.2558,190
8027.233.224.0/1927.233.224.1 to 27.233.255.25427.233.255.2558,190
8127.234.0.0/1927.234.0.1 to 27.234.31.25427.234.31.2558,190
8227.234.32.0/1927.234.32.1 to 27.234.63.25427.234.63.2558,190
8327.234.64.0/1927.234.64.1 to 27.234.95.25427.234.95.2558,190
8427.234.96.0/1927.234.96.1 to 27.234.127.25427.234.127.2558,190
8527.234.128.0/1927.234.128.1 to 27.234.159.25427.234.159.2558,190
8627.234.160.0/1927.234.160.1 to 27.234.191.25427.234.191.2558,190
8727.234.192.0/1927.234.192.1 to 27.234.223.25427.234.223.2558,190
8827.234.224.0/1927.234.224.1 to 27.234.255.25427.234.255.2558,190
8927.235.0.0/1927.235.0.1 to 27.235.31.25427.235.31.2558,190
9027.235.32.0/1927.235.32.1 to 27.235.63.25427.235.63.2558,190
9127.235.64.0/1927.235.64.1 to 27.235.95.25427.235.95.2558,190
9227.235.96.0/1927.235.96.1 to 27.235.127.25427.235.127.2558,190
9327.235.128.0/1927.235.128.1 to 27.235.159.25427.235.159.2558,190
9427.235.160.0/1927.235.160.1 to 27.235.191.25427.235.191.2558,190
9527.235.192.0/1927.235.192.1 to 27.235.223.25427.235.223.2558,190
9627.235.224.0/1927.235.224.1 to 27.235.255.25427.235.255.2558,190
9727.236.0.0/1927.236.0.1 to 27.236.31.25427.236.31.2558,190
9827.236.32.0/1927.236.32.1 to 27.236.63.25427.236.63.2558,190
9927.236.64.0/1927.236.64.1 to 27.236.95.25427.236.95.2558,190
10027.236.96.0/1927.236.96.1 to 27.236.127.25427.236.127.2558,190
10127.236.128.0/1927.236.128.1 to 27.236.159.25427.236.159.2558,190
10227.236.160.0/1927.236.160.1 to 27.236.191.25427.236.191.2558,190
10327.236.192.0/1927.236.192.1 to 27.236.223.25427.236.223.2558,190
10427.236.224.0/1927.236.224.1 to 27.236.255.25427.236.255.2558,190
10527.237.0.0/1927.237.0.1 to 27.237.31.25427.237.31.2558,190
10627.237.32.0/1927.237.32.1 to 27.237.63.25427.237.63.2558,190
10727.237.64.0/1927.237.64.1 to 27.237.95.25427.237.95.2558,190
10827.237.96.0/1927.237.96.1 to 27.237.127.25427.237.127.2558,190
10927.237.128.0/1927.237.128.1 to 27.237.159.25427.237.159.2558,190
11027.237.160.0/1927.237.160.1 to 27.237.191.25427.237.191.2558,190
11127.237.192.0/1927.237.192.1 to 27.237.223.25427.237.223.2558,190
11227.237.224.0/1927.237.224.1 to 27.237.255.25427.237.255.2558,190
11327.238.0.0/1927.238.0.1 to 27.238.31.25427.238.31.2558,190
11427.238.32.0/1927.238.32.1 to 27.238.63.25427.238.63.2558,190
11527.238.64.0/1927.238.64.1 to 27.238.95.25427.238.95.2558,190
11627.238.96.0/1927.238.96.1 to 27.238.127.25427.238.127.2558,190
11727.238.128.0/1927.238.128.1 to 27.238.159.25427.238.159.2558,190
11827.238.160.0/1927.238.160.1 to 27.238.191.25427.238.191.2558,190
11927.238.192.0/1927.238.192.1 to 27.238.223.25427.238.223.2558,190
12027.238.224.0/1927.238.224.1 to 27.238.255.25427.238.255.2558,190
12127.239.0.0/1927.239.0.1 to 27.239.31.25427.239.31.2558,190
12227.239.32.0/1927.239.32.1 to 27.239.63.25427.239.63.2558,190
12327.239.64.0/1927.239.64.1 to 27.239.95.25427.239.95.2558,190
12427.239.96.0/1927.239.96.1 to 27.239.127.25427.239.127.2558,190
12527.239.128.0/1927.239.128.1 to 27.239.159.25427.239.159.2558,190
12627.239.160.0/1927.239.160.1 to 27.239.191.25427.239.191.2558,190
12727.239.192.0/1927.239.192.1 to 27.239.223.25427.239.223.2558,190
12827.239.224.0/1927.239.224.1 to 27.239.255.25427.239.255.2558,190
12927.240.0.0/1927.240.0.1 to 27.240.31.25427.240.31.2558,190
13027.240.32.0/1927.240.32.1 to 27.240.63.25427.240.63.2558,190
13127.240.64.0/1927.240.64.1 to 27.240.95.25427.240.95.2558,190
13227.240.96.0/1927.240.96.1 to 27.240.127.25427.240.127.2558,190
13327.240.128.0/1927.240.128.1 to 27.240.159.25427.240.159.2558,190
13427.240.160.0/1927.240.160.1 to 27.240.191.25427.240.191.2558,190
13527.240.192.0/1927.240.192.1 to 27.240.223.25427.240.223.2558,190
13627.240.224.0/1927.240.224.1 to 27.240.255.25427.240.255.2558,190
13727.241.0.0/1927.241.0.1 to 27.241.31.25427.241.31.2558,190
13827.241.32.0/1927.241.32.1 to 27.241.63.25427.241.63.2558,190
13927.241.64.0/1927.241.64.1 to 27.241.95.25427.241.95.2558,190
14027.241.96.0/1927.241.96.1 to 27.241.127.25427.241.127.2558,190
14127.241.128.0/1927.241.128.1 to 27.241.159.25427.241.159.2558,190
14227.241.160.0/1927.241.160.1 to 27.241.191.25427.241.191.2558,190
14327.241.192.0/1927.241.192.1 to 27.241.223.25427.241.223.2558,190
14427.241.224.0/1927.241.224.1 to 27.241.255.25427.241.255.2558,190
14527.242.0.0/1927.242.0.1 to 27.242.31.25427.242.31.2558,190
14627.242.32.0/1927.242.32.1 to 27.242.63.25427.242.63.2558,190
14727.242.64.0/1927.242.64.1 to 27.242.95.25427.242.95.2558,190
14827.242.96.0/1927.242.96.1 to 27.242.127.25427.242.127.2558,190
14927.242.128.0/1927.242.128.1 to 27.242.159.25427.242.159.2558,190
15027.242.160.0/1927.242.160.1 to 27.242.191.25427.242.191.2558,190
15127.242.192.0/1927.242.192.1 to 27.242.223.25427.242.223.2558,190
15227.242.224.0/1927.242.224.1 to 27.242.255.25427.242.255.2558,190
15327.243.0.0/1927.243.0.1 to 27.243.31.25427.243.31.2558,190
15427.243.32.0/1927.243.32.1 to 27.243.63.25427.243.63.2558,190
15527.243.64.0/1927.243.64.1 to 27.243.95.25427.243.95.2558,190
15627.243.96.0/1927.243.96.1 to 27.243.127.25427.243.127.2558,190
15727.243.128.0/1927.243.128.1 to 27.243.159.25427.243.159.2558,190
15827.243.160.0/1927.243.160.1 to 27.243.191.25427.243.191.2558,190
15927.243.192.0/1927.243.192.1 to 27.243.223.25427.243.223.2558,190
16027.243.224.0/1927.243.224.1 to 27.243.255.25427.243.255.2558,190
16127.244.0.0/1927.244.0.1 to 27.244.31.25427.244.31.2558,190
16227.244.32.0/1927.244.32.1 to 27.244.63.25427.244.63.2558,190
16327.244.64.0/1927.244.64.1 to 27.244.95.25427.244.95.2558,190
16427.244.96.0/1927.244.96.1 to 27.244.127.25427.244.127.2558,190
16527.244.128.0/1927.244.128.1 to 27.244.159.25427.244.159.2558,190
16627.244.160.0/1927.244.160.1 to 27.244.191.25427.244.191.2558,190
16727.244.192.0/1927.244.192.1 to 27.244.223.25427.244.223.2558,190
16827.244.224.0/1927.244.224.1 to 27.244.255.25427.244.255.2558,190
16927.245.0.0/1927.245.0.1 to 27.245.31.25427.245.31.2558,190
17027.245.32.0/1927.245.32.1 to 27.245.63.25427.245.63.2558,190
17127.245.64.0/1927.245.64.1 to 27.245.95.25427.245.95.2558,190
17227.245.96.0/1927.245.96.1 to 27.245.127.25427.245.127.2558,190
17327.245.128.0/1927.245.128.1 to 27.245.159.25427.245.159.2558,190
17427.245.160.0/1927.245.160.1 to 27.245.191.25427.245.191.2558,190
17527.245.192.0/1927.245.192.1 to 27.245.223.25427.245.223.2558,190
17627.245.224.0/1927.245.224.1 to 27.245.255.25427.245.255.2558,190
17727.246.0.0/1927.246.0.1 to 27.246.31.25427.246.31.2558,190
17827.246.32.0/1927.246.32.1 to 27.246.63.25427.246.63.2558,190
17927.246.64.0/1927.246.64.1 to 27.246.95.25427.246.95.2558,190
18027.246.96.0/1927.246.96.1 to 27.246.127.25427.246.127.2558,190
18127.246.128.0/1927.246.128.1 to 27.246.159.25427.246.159.2558,190
18227.246.160.0/1927.246.160.1 to 27.246.191.25427.246.191.2558,190
18327.246.192.0/1927.246.192.1 to 27.246.223.25427.246.223.2558,190
18427.246.224.0/1927.246.224.1 to 27.246.255.25427.246.255.2558,190
18527.247.0.0/1927.247.0.1 to 27.247.31.25427.247.31.2558,190
18627.247.32.0/1927.247.32.1 to 27.247.63.25427.247.63.2558,190
18727.247.64.0/1927.247.64.1 to 27.247.95.25427.247.95.2558,190
18827.247.96.0/1927.247.96.1 to 27.247.127.25427.247.127.2558,190
18927.247.128.0/1927.247.128.1 to 27.247.159.25427.247.159.2558,190
19027.247.160.0/1927.247.160.1 to 27.247.191.25427.247.191.2558,190
19127.247.192.0/1927.247.192.1 to 27.247.223.25427.247.223.2558,190
19227.247.224.0/1927.247.224.1 to 27.247.255.25427.247.255.2558,190
19327.248.0.0/1927.248.0.1 to 27.248.31.25427.248.31.2558,190
19427.248.32.0/1927.248.32.1 to 27.248.63.25427.248.63.2558,190
19527.248.64.0/1927.248.64.1 to 27.248.95.25427.248.95.2558,190
19627.248.96.0/1927.248.96.1 to 27.248.127.25427.248.127.2558,190
19727.248.128.0/1927.248.128.1 to 27.248.159.25427.248.159.2558,190
19827.248.160.0/1927.248.160.1 to 27.248.191.25427.248.191.2558,190
19927.248.192.0/1927.248.192.1 to 27.248.223.25427.248.223.2558,190
20027.248.224.0/1927.248.224.1 to 27.248.255.25427.248.255.2558,190
20127.249.0.0/1927.249.0.1 to 27.249.31.25427.249.31.2558,190
20227.249.32.0/1927.249.32.1 to 27.249.63.25427.249.63.2558,190
20327.249.64.0/1927.249.64.1 to 27.249.95.25427.249.95.2558,190
20427.249.96.0/1927.249.96.1 to 27.249.127.25427.249.127.2558,190
20527.249.128.0/1927.249.128.1 to 27.249.159.25427.249.159.2558,190
20627.249.160.0/1927.249.160.1 to 27.249.191.25427.249.191.2558,190
20727.249.192.0/1927.249.192.1 to 27.249.223.25427.249.223.2558,190
20827.249.224.0/1927.249.224.1 to 27.249.255.25427.249.255.2558,190
20927.250.0.0/1927.250.0.1 to 27.250.31.25427.250.31.2558,190
21027.250.32.0/1927.250.32.1 to 27.250.63.25427.250.63.2558,190
21127.250.64.0/1927.250.64.1 to 27.250.95.25427.250.95.2558,190
21227.250.96.0/1927.250.96.1 to 27.250.127.25427.250.127.2558,190
21327.250.128.0/1927.250.128.1 to 27.250.159.25427.250.159.2558,190
21427.250.160.0/1927.250.160.1 to 27.250.191.25427.250.191.2558,190
21527.250.192.0/1927.250.192.1 to 27.250.223.25427.250.223.2558,190
21627.250.224.0/1927.250.224.1 to 27.250.255.25427.250.255.2558,190
21727.251.0.0/1927.251.0.1 to 27.251.31.25427.251.31.2558,190
21827.251.32.0/1927.251.32.1 to 27.251.63.25427.251.63.2558,190
21927.251.64.0/1927.251.64.1 to 27.251.95.25427.251.95.2558,190
22027.251.96.0/1927.251.96.1 to 27.251.127.25427.251.127.2558,190
22127.251.128.0/1927.251.128.1 to 27.251.159.25427.251.159.2558,190
22227.251.160.0/1927.251.160.1 to 27.251.191.25427.251.191.2558,190
22327.251.192.0/1927.251.192.1 to 27.251.223.25427.251.223.2558,190
22427.251.224.0/1927.251.224.1 to 27.251.255.25427.251.255.2558,190
22527.252.0.0/1927.252.0.1 to 27.252.31.25427.252.31.2558,190
22627.252.32.0/1927.252.32.1 to 27.252.63.25427.252.63.2558,190
22727.252.64.0/1927.252.64.1 to 27.252.95.25427.252.95.2558,190
22827.252.96.0/1927.252.96.1 to 27.252.127.25427.252.127.2558,190
22927.252.128.0/1927.252.128.1 to 27.252.159.25427.252.159.2558,190
23027.252.160.0/1927.252.160.1 to 27.252.191.25427.252.191.2558,190
23127.252.192.0/1927.252.192.1 to 27.252.223.25427.252.223.2558,190
23227.252.224.0/1927.252.224.1 to 27.252.255.25427.252.255.2558,190
23327.253.0.0/1927.253.0.1 to 27.253.31.25427.253.31.2558,190
23427.253.32.0/1927.253.32.1 to 27.253.63.25427.253.63.2558,190
23527.253.64.0/1927.253.64.1 to 27.253.95.25427.253.95.2558,190
23627.253.96.0/1927.253.96.1 to 27.253.127.25427.253.127.2558,190
23727.253.128.0/1927.253.128.1 to 27.253.159.25427.253.159.2558,190
23827.253.160.0/1927.253.160.1 to 27.253.191.25427.253.191.2558,190
23927.253.192.0/1927.253.192.1 to 27.253.223.25427.253.223.2558,190
24027.253.224.0/1927.253.224.1 to 27.253.255.25427.253.255.2558,190
24127.254.0.0/1927.254.0.1 to 27.254.31.25427.254.31.2558,190
24227.254.32.0/1927.254.32.1 to 27.254.63.25427.254.63.2558,190
24327.254.64.0/1927.254.64.1 to 27.254.95.25427.254.95.2558,190
24427.254.96.0/1927.254.96.1 to 27.254.127.25427.254.127.2558,190
24527.254.128.0/1927.254.128.1 to 27.254.159.25427.254.159.2558,190
24627.254.160.0/1927.254.160.1 to 27.254.191.25427.254.191.2558,190
24727.254.192.0/1927.254.192.1 to 27.254.223.25427.254.223.2558,190
24827.254.224.0/1927.254.224.1 to 27.254.255.25427.254.255.2558,190
24927.255.0.0/1927.255.0.1 to 27.255.31.25427.255.31.2558,190
25027.255.32.0/1927.255.32.1 to 27.255.63.25427.255.63.2558,190
25127.255.64.0/1927.255.64.1 to 27.255.95.25427.255.95.2558,190
25227.255.96.0/1927.255.96.1 to 27.255.127.25427.255.127.2558,190
25327.255.128.0/1927.255.128.1 to 27.255.159.25427.255.159.2558,190
25427.255.160.0/1927.255.160.1 to 27.255.191.25427.255.191.2558,190
25527.255.192.0/1927.255.192.1 to 27.255.223.25427.255.223.2558,190
25627.255.224.0/1927.255.224.1 to 27.255.255.25427.255.255.2558,190

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.