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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.

Network54.128.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
54.128.0.0
Broadcast address
54.191.255.255
First usable
54.128.0.1
Last usable
54.191.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
A (default /8)
As numbers
Hex 36800000 · Integer 914358272 to 918552575
Reverse DNS zones
128.54.in-addr.arpa
129.54.in-addr.arpa
130.54.in-addr.arpa
131.54.in-addr.arpa
132.54.in-addr.arpa
133.54.in-addr.arpa
134.54.in-addr.arpa
135.54.in-addr.arpa
136.54.in-addr.arpa
137.54.in-addr.arpa
138.54.in-addr.arpa
139.54.in-addr.arpa
140.54.in-addr.arpa
141.54.in-addr.arpa
142.54.in-addr.arpa
143.54.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110110.10000000.00000000.0000000054.128.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network00110110.10000000.00000000.0000000054.128.0.0
Broadcast00110110.10111111.11111111.1111111154.191.255.255
Split into smaller subnets/19
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

54.128.0.0/10 makes 512 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
154.128.0.0/1954.128.0.1 to 54.128.31.25454.128.31.2558,190
254.128.32.0/1954.128.32.1 to 54.128.63.25454.128.63.2558,190
354.128.64.0/1954.128.64.1 to 54.128.95.25454.128.95.2558,190
454.128.96.0/1954.128.96.1 to 54.128.127.25454.128.127.2558,190
554.128.128.0/1954.128.128.1 to 54.128.159.25454.128.159.2558,190
654.128.160.0/1954.128.160.1 to 54.128.191.25454.128.191.2558,190
754.128.192.0/1954.128.192.1 to 54.128.223.25454.128.223.2558,190
854.128.224.0/1954.128.224.1 to 54.128.255.25454.128.255.2558,190
954.129.0.0/1954.129.0.1 to 54.129.31.25454.129.31.2558,190
1054.129.32.0/1954.129.32.1 to 54.129.63.25454.129.63.2558,190
1154.129.64.0/1954.129.64.1 to 54.129.95.25454.129.95.2558,190
1254.129.96.0/1954.129.96.1 to 54.129.127.25454.129.127.2558,190
1354.129.128.0/1954.129.128.1 to 54.129.159.25454.129.159.2558,190
1454.129.160.0/1954.129.160.1 to 54.129.191.25454.129.191.2558,190
1554.129.192.0/1954.129.192.1 to 54.129.223.25454.129.223.2558,190
1654.129.224.0/1954.129.224.1 to 54.129.255.25454.129.255.2558,190
1754.130.0.0/1954.130.0.1 to 54.130.31.25454.130.31.2558,190
1854.130.32.0/1954.130.32.1 to 54.130.63.25454.130.63.2558,190
1954.130.64.0/1954.130.64.1 to 54.130.95.25454.130.95.2558,190
2054.130.96.0/1954.130.96.1 to 54.130.127.25454.130.127.2558,190
2154.130.128.0/1954.130.128.1 to 54.130.159.25454.130.159.2558,190
2254.130.160.0/1954.130.160.1 to 54.130.191.25454.130.191.2558,190
2354.130.192.0/1954.130.192.1 to 54.130.223.25454.130.223.2558,190
2454.130.224.0/1954.130.224.1 to 54.130.255.25454.130.255.2558,190
2554.131.0.0/1954.131.0.1 to 54.131.31.25454.131.31.2558,190
2654.131.32.0/1954.131.32.1 to 54.131.63.25454.131.63.2558,190
2754.131.64.0/1954.131.64.1 to 54.131.95.25454.131.95.2558,190
2854.131.96.0/1954.131.96.1 to 54.131.127.25454.131.127.2558,190
2954.131.128.0/1954.131.128.1 to 54.131.159.25454.131.159.2558,190
3054.131.160.0/1954.131.160.1 to 54.131.191.25454.131.191.2558,190
3154.131.192.0/1954.131.192.1 to 54.131.223.25454.131.223.2558,190
3254.131.224.0/1954.131.224.1 to 54.131.255.25454.131.255.2558,190
3354.132.0.0/1954.132.0.1 to 54.132.31.25454.132.31.2558,190
3454.132.32.0/1954.132.32.1 to 54.132.63.25454.132.63.2558,190
3554.132.64.0/1954.132.64.1 to 54.132.95.25454.132.95.2558,190
3654.132.96.0/1954.132.96.1 to 54.132.127.25454.132.127.2558,190
3754.132.128.0/1954.132.128.1 to 54.132.159.25454.132.159.2558,190
3854.132.160.0/1954.132.160.1 to 54.132.191.25454.132.191.2558,190
3954.132.192.0/1954.132.192.1 to 54.132.223.25454.132.223.2558,190
4054.132.224.0/1954.132.224.1 to 54.132.255.25454.132.255.2558,190
4154.133.0.0/1954.133.0.1 to 54.133.31.25454.133.31.2558,190
4254.133.32.0/1954.133.32.1 to 54.133.63.25454.133.63.2558,190
4354.133.64.0/1954.133.64.1 to 54.133.95.25454.133.95.2558,190
4454.133.96.0/1954.133.96.1 to 54.133.127.25454.133.127.2558,190
4554.133.128.0/1954.133.128.1 to 54.133.159.25454.133.159.2558,190
4654.133.160.0/1954.133.160.1 to 54.133.191.25454.133.191.2558,190
4754.133.192.0/1954.133.192.1 to 54.133.223.25454.133.223.2558,190
4854.133.224.0/1954.133.224.1 to 54.133.255.25454.133.255.2558,190
4954.134.0.0/1954.134.0.1 to 54.134.31.25454.134.31.2558,190
5054.134.32.0/1954.134.32.1 to 54.134.63.25454.134.63.2558,190
5154.134.64.0/1954.134.64.1 to 54.134.95.25454.134.95.2558,190
5254.134.96.0/1954.134.96.1 to 54.134.127.25454.134.127.2558,190
5354.134.128.0/1954.134.128.1 to 54.134.159.25454.134.159.2558,190
5454.134.160.0/1954.134.160.1 to 54.134.191.25454.134.191.2558,190
5554.134.192.0/1954.134.192.1 to 54.134.223.25454.134.223.2558,190
5654.134.224.0/1954.134.224.1 to 54.134.255.25454.134.255.2558,190
5754.135.0.0/1954.135.0.1 to 54.135.31.25454.135.31.2558,190
5854.135.32.0/1954.135.32.1 to 54.135.63.25454.135.63.2558,190
5954.135.64.0/1954.135.64.1 to 54.135.95.25454.135.95.2558,190
6054.135.96.0/1954.135.96.1 to 54.135.127.25454.135.127.2558,190
6154.135.128.0/1954.135.128.1 to 54.135.159.25454.135.159.2558,190
6254.135.160.0/1954.135.160.1 to 54.135.191.25454.135.191.2558,190
6354.135.192.0/1954.135.192.1 to 54.135.223.25454.135.223.2558,190
6454.135.224.0/1954.135.224.1 to 54.135.255.25454.135.255.2558,190
6554.136.0.0/1954.136.0.1 to 54.136.31.25454.136.31.2558,190
6654.136.32.0/1954.136.32.1 to 54.136.63.25454.136.63.2558,190
6754.136.64.0/1954.136.64.1 to 54.136.95.25454.136.95.2558,190
6854.136.96.0/1954.136.96.1 to 54.136.127.25454.136.127.2558,190
6954.136.128.0/1954.136.128.1 to 54.136.159.25454.136.159.2558,190
7054.136.160.0/1954.136.160.1 to 54.136.191.25454.136.191.2558,190
7154.136.192.0/1954.136.192.1 to 54.136.223.25454.136.223.2558,190
7254.136.224.0/1954.136.224.1 to 54.136.255.25454.136.255.2558,190
7354.137.0.0/1954.137.0.1 to 54.137.31.25454.137.31.2558,190
7454.137.32.0/1954.137.32.1 to 54.137.63.25454.137.63.2558,190
7554.137.64.0/1954.137.64.1 to 54.137.95.25454.137.95.2558,190
7654.137.96.0/1954.137.96.1 to 54.137.127.25454.137.127.2558,190
7754.137.128.0/1954.137.128.1 to 54.137.159.25454.137.159.2558,190
7854.137.160.0/1954.137.160.1 to 54.137.191.25454.137.191.2558,190
7954.137.192.0/1954.137.192.1 to 54.137.223.25454.137.223.2558,190
8054.137.224.0/1954.137.224.1 to 54.137.255.25454.137.255.2558,190
8154.138.0.0/1954.138.0.1 to 54.138.31.25454.138.31.2558,190
8254.138.32.0/1954.138.32.1 to 54.138.63.25454.138.63.2558,190
8354.138.64.0/1954.138.64.1 to 54.138.95.25454.138.95.2558,190
8454.138.96.0/1954.138.96.1 to 54.138.127.25454.138.127.2558,190
8554.138.128.0/1954.138.128.1 to 54.138.159.25454.138.159.2558,190
8654.138.160.0/1954.138.160.1 to 54.138.191.25454.138.191.2558,190
8754.138.192.0/1954.138.192.1 to 54.138.223.25454.138.223.2558,190
8854.138.224.0/1954.138.224.1 to 54.138.255.25454.138.255.2558,190
8954.139.0.0/1954.139.0.1 to 54.139.31.25454.139.31.2558,190
9054.139.32.0/1954.139.32.1 to 54.139.63.25454.139.63.2558,190
9154.139.64.0/1954.139.64.1 to 54.139.95.25454.139.95.2558,190
9254.139.96.0/1954.139.96.1 to 54.139.127.25454.139.127.2558,190
9354.139.128.0/1954.139.128.1 to 54.139.159.25454.139.159.2558,190
9454.139.160.0/1954.139.160.1 to 54.139.191.25454.139.191.2558,190
9554.139.192.0/1954.139.192.1 to 54.139.223.25454.139.223.2558,190
9654.139.224.0/1954.139.224.1 to 54.139.255.25454.139.255.2558,190
9754.140.0.0/1954.140.0.1 to 54.140.31.25454.140.31.2558,190
9854.140.32.0/1954.140.32.1 to 54.140.63.25454.140.63.2558,190
9954.140.64.0/1954.140.64.1 to 54.140.95.25454.140.95.2558,190
10054.140.96.0/1954.140.96.1 to 54.140.127.25454.140.127.2558,190
10154.140.128.0/1954.140.128.1 to 54.140.159.25454.140.159.2558,190
10254.140.160.0/1954.140.160.1 to 54.140.191.25454.140.191.2558,190
10354.140.192.0/1954.140.192.1 to 54.140.223.25454.140.223.2558,190
10454.140.224.0/1954.140.224.1 to 54.140.255.25454.140.255.2558,190
10554.141.0.0/1954.141.0.1 to 54.141.31.25454.141.31.2558,190
10654.141.32.0/1954.141.32.1 to 54.141.63.25454.141.63.2558,190
10754.141.64.0/1954.141.64.1 to 54.141.95.25454.141.95.2558,190
10854.141.96.0/1954.141.96.1 to 54.141.127.25454.141.127.2558,190
10954.141.128.0/1954.141.128.1 to 54.141.159.25454.141.159.2558,190
11054.141.160.0/1954.141.160.1 to 54.141.191.25454.141.191.2558,190
11154.141.192.0/1954.141.192.1 to 54.141.223.25454.141.223.2558,190
11254.141.224.0/1954.141.224.1 to 54.141.255.25454.141.255.2558,190
11354.142.0.0/1954.142.0.1 to 54.142.31.25454.142.31.2558,190
11454.142.32.0/1954.142.32.1 to 54.142.63.25454.142.63.2558,190
11554.142.64.0/1954.142.64.1 to 54.142.95.25454.142.95.2558,190
11654.142.96.0/1954.142.96.1 to 54.142.127.25454.142.127.2558,190
11754.142.128.0/1954.142.128.1 to 54.142.159.25454.142.159.2558,190
11854.142.160.0/1954.142.160.1 to 54.142.191.25454.142.191.2558,190
11954.142.192.0/1954.142.192.1 to 54.142.223.25454.142.223.2558,190
12054.142.224.0/1954.142.224.1 to 54.142.255.25454.142.255.2558,190
12154.143.0.0/1954.143.0.1 to 54.143.31.25454.143.31.2558,190
12254.143.32.0/1954.143.32.1 to 54.143.63.25454.143.63.2558,190
12354.143.64.0/1954.143.64.1 to 54.143.95.25454.143.95.2558,190
12454.143.96.0/1954.143.96.1 to 54.143.127.25454.143.127.2558,190
12554.143.128.0/1954.143.128.1 to 54.143.159.25454.143.159.2558,190
12654.143.160.0/1954.143.160.1 to 54.143.191.25454.143.191.2558,190
12754.143.192.0/1954.143.192.1 to 54.143.223.25454.143.223.2558,190
12854.143.224.0/1954.143.224.1 to 54.143.255.25454.143.255.2558,190
12954.144.0.0/1954.144.0.1 to 54.144.31.25454.144.31.2558,190
13054.144.32.0/1954.144.32.1 to 54.144.63.25454.144.63.2558,190
13154.144.64.0/1954.144.64.1 to 54.144.95.25454.144.95.2558,190
13254.144.96.0/1954.144.96.1 to 54.144.127.25454.144.127.2558,190
13354.144.128.0/1954.144.128.1 to 54.144.159.25454.144.159.2558,190
13454.144.160.0/1954.144.160.1 to 54.144.191.25454.144.191.2558,190
13554.144.192.0/1954.144.192.1 to 54.144.223.25454.144.223.2558,190
13654.144.224.0/1954.144.224.1 to 54.144.255.25454.144.255.2558,190
13754.145.0.0/1954.145.0.1 to 54.145.31.25454.145.31.2558,190
13854.145.32.0/1954.145.32.1 to 54.145.63.25454.145.63.2558,190
13954.145.64.0/1954.145.64.1 to 54.145.95.25454.145.95.2558,190
14054.145.96.0/1954.145.96.1 to 54.145.127.25454.145.127.2558,190
14154.145.128.0/1954.145.128.1 to 54.145.159.25454.145.159.2558,190
14254.145.160.0/1954.145.160.1 to 54.145.191.25454.145.191.2558,190
14354.145.192.0/1954.145.192.1 to 54.145.223.25454.145.223.2558,190
14454.145.224.0/1954.145.224.1 to 54.145.255.25454.145.255.2558,190
14554.146.0.0/1954.146.0.1 to 54.146.31.25454.146.31.2558,190
14654.146.32.0/1954.146.32.1 to 54.146.63.25454.146.63.2558,190
14754.146.64.0/1954.146.64.1 to 54.146.95.25454.146.95.2558,190
14854.146.96.0/1954.146.96.1 to 54.146.127.25454.146.127.2558,190
14954.146.128.0/1954.146.128.1 to 54.146.159.25454.146.159.2558,190
15054.146.160.0/1954.146.160.1 to 54.146.191.25454.146.191.2558,190
15154.146.192.0/1954.146.192.1 to 54.146.223.25454.146.223.2558,190
15254.146.224.0/1954.146.224.1 to 54.146.255.25454.146.255.2558,190
15354.147.0.0/1954.147.0.1 to 54.147.31.25454.147.31.2558,190
15454.147.32.0/1954.147.32.1 to 54.147.63.25454.147.63.2558,190
15554.147.64.0/1954.147.64.1 to 54.147.95.25454.147.95.2558,190
15654.147.96.0/1954.147.96.1 to 54.147.127.25454.147.127.2558,190
15754.147.128.0/1954.147.128.1 to 54.147.159.25454.147.159.2558,190
15854.147.160.0/1954.147.160.1 to 54.147.191.25454.147.191.2558,190
15954.147.192.0/1954.147.192.1 to 54.147.223.25454.147.223.2558,190
16054.147.224.0/1954.147.224.1 to 54.147.255.25454.147.255.2558,190
16154.148.0.0/1954.148.0.1 to 54.148.31.25454.148.31.2558,190
16254.148.32.0/1954.148.32.1 to 54.148.63.25454.148.63.2558,190
16354.148.64.0/1954.148.64.1 to 54.148.95.25454.148.95.2558,190
16454.148.96.0/1954.148.96.1 to 54.148.127.25454.148.127.2558,190
16554.148.128.0/1954.148.128.1 to 54.148.159.25454.148.159.2558,190
16654.148.160.0/1954.148.160.1 to 54.148.191.25454.148.191.2558,190
16754.148.192.0/1954.148.192.1 to 54.148.223.25454.148.223.2558,190
16854.148.224.0/1954.148.224.1 to 54.148.255.25454.148.255.2558,190
16954.149.0.0/1954.149.0.1 to 54.149.31.25454.149.31.2558,190
17054.149.32.0/1954.149.32.1 to 54.149.63.25454.149.63.2558,190
17154.149.64.0/1954.149.64.1 to 54.149.95.25454.149.95.2558,190
17254.149.96.0/1954.149.96.1 to 54.149.127.25454.149.127.2558,190
17354.149.128.0/1954.149.128.1 to 54.149.159.25454.149.159.2558,190
17454.149.160.0/1954.149.160.1 to 54.149.191.25454.149.191.2558,190
17554.149.192.0/1954.149.192.1 to 54.149.223.25454.149.223.2558,190
17654.149.224.0/1954.149.224.1 to 54.149.255.25454.149.255.2558,190
17754.150.0.0/1954.150.0.1 to 54.150.31.25454.150.31.2558,190
17854.150.32.0/1954.150.32.1 to 54.150.63.25454.150.63.2558,190
17954.150.64.0/1954.150.64.1 to 54.150.95.25454.150.95.2558,190
18054.150.96.0/1954.150.96.1 to 54.150.127.25454.150.127.2558,190
18154.150.128.0/1954.150.128.1 to 54.150.159.25454.150.159.2558,190
18254.150.160.0/1954.150.160.1 to 54.150.191.25454.150.191.2558,190
18354.150.192.0/1954.150.192.1 to 54.150.223.25454.150.223.2558,190
18454.150.224.0/1954.150.224.1 to 54.150.255.25454.150.255.2558,190
18554.151.0.0/1954.151.0.1 to 54.151.31.25454.151.31.2558,190
18654.151.32.0/1954.151.32.1 to 54.151.63.25454.151.63.2558,190
18754.151.64.0/1954.151.64.1 to 54.151.95.25454.151.95.2558,190
18854.151.96.0/1954.151.96.1 to 54.151.127.25454.151.127.2558,190
18954.151.128.0/1954.151.128.1 to 54.151.159.25454.151.159.2558,190
19054.151.160.0/1954.151.160.1 to 54.151.191.25454.151.191.2558,190
19154.151.192.0/1954.151.192.1 to 54.151.223.25454.151.223.2558,190
19254.151.224.0/1954.151.224.1 to 54.151.255.25454.151.255.2558,190
19354.152.0.0/1954.152.0.1 to 54.152.31.25454.152.31.2558,190
19454.152.32.0/1954.152.32.1 to 54.152.63.25454.152.63.2558,190
19554.152.64.0/1954.152.64.1 to 54.152.95.25454.152.95.2558,190
19654.152.96.0/1954.152.96.1 to 54.152.127.25454.152.127.2558,190
19754.152.128.0/1954.152.128.1 to 54.152.159.25454.152.159.2558,190
19854.152.160.0/1954.152.160.1 to 54.152.191.25454.152.191.2558,190
19954.152.192.0/1954.152.192.1 to 54.152.223.25454.152.223.2558,190
20054.152.224.0/1954.152.224.1 to 54.152.255.25454.152.255.2558,190
20154.153.0.0/1954.153.0.1 to 54.153.31.25454.153.31.2558,190
20254.153.32.0/1954.153.32.1 to 54.153.63.25454.153.63.2558,190
20354.153.64.0/1954.153.64.1 to 54.153.95.25454.153.95.2558,190
20454.153.96.0/1954.153.96.1 to 54.153.127.25454.153.127.2558,190
20554.153.128.0/1954.153.128.1 to 54.153.159.25454.153.159.2558,190
20654.153.160.0/1954.153.160.1 to 54.153.191.25454.153.191.2558,190
20754.153.192.0/1954.153.192.1 to 54.153.223.25454.153.223.2558,190
20854.153.224.0/1954.153.224.1 to 54.153.255.25454.153.255.2558,190
20954.154.0.0/1954.154.0.1 to 54.154.31.25454.154.31.2558,190
21054.154.32.0/1954.154.32.1 to 54.154.63.25454.154.63.2558,190
21154.154.64.0/1954.154.64.1 to 54.154.95.25454.154.95.2558,190
21254.154.96.0/1954.154.96.1 to 54.154.127.25454.154.127.2558,190
21354.154.128.0/1954.154.128.1 to 54.154.159.25454.154.159.2558,190
21454.154.160.0/1954.154.160.1 to 54.154.191.25454.154.191.2558,190
21554.154.192.0/1954.154.192.1 to 54.154.223.25454.154.223.2558,190
21654.154.224.0/1954.154.224.1 to 54.154.255.25454.154.255.2558,190
21754.155.0.0/1954.155.0.1 to 54.155.31.25454.155.31.2558,190
21854.155.32.0/1954.155.32.1 to 54.155.63.25454.155.63.2558,190
21954.155.64.0/1954.155.64.1 to 54.155.95.25454.155.95.2558,190
22054.155.96.0/1954.155.96.1 to 54.155.127.25454.155.127.2558,190
22154.155.128.0/1954.155.128.1 to 54.155.159.25454.155.159.2558,190
22254.155.160.0/1954.155.160.1 to 54.155.191.25454.155.191.2558,190
22354.155.192.0/1954.155.192.1 to 54.155.223.25454.155.223.2558,190
22454.155.224.0/1954.155.224.1 to 54.155.255.25454.155.255.2558,190
22554.156.0.0/1954.156.0.1 to 54.156.31.25454.156.31.2558,190
22654.156.32.0/1954.156.32.1 to 54.156.63.25454.156.63.2558,190
22754.156.64.0/1954.156.64.1 to 54.156.95.25454.156.95.2558,190
22854.156.96.0/1954.156.96.1 to 54.156.127.25454.156.127.2558,190
22954.156.128.0/1954.156.128.1 to 54.156.159.25454.156.159.2558,190
23054.156.160.0/1954.156.160.1 to 54.156.191.25454.156.191.2558,190
23154.156.192.0/1954.156.192.1 to 54.156.223.25454.156.223.2558,190
23254.156.224.0/1954.156.224.1 to 54.156.255.25454.156.255.2558,190
23354.157.0.0/1954.157.0.1 to 54.157.31.25454.157.31.2558,190
23454.157.32.0/1954.157.32.1 to 54.157.63.25454.157.63.2558,190
23554.157.64.0/1954.157.64.1 to 54.157.95.25454.157.95.2558,190
23654.157.96.0/1954.157.96.1 to 54.157.127.25454.157.127.2558,190
23754.157.128.0/1954.157.128.1 to 54.157.159.25454.157.159.2558,190
23854.157.160.0/1954.157.160.1 to 54.157.191.25454.157.191.2558,190
23954.157.192.0/1954.157.192.1 to 54.157.223.25454.157.223.2558,190
24054.157.224.0/1954.157.224.1 to 54.157.255.25454.157.255.2558,190
24154.158.0.0/1954.158.0.1 to 54.158.31.25454.158.31.2558,190
24254.158.32.0/1954.158.32.1 to 54.158.63.25454.158.63.2558,190
24354.158.64.0/1954.158.64.1 to 54.158.95.25454.158.95.2558,190
24454.158.96.0/1954.158.96.1 to 54.158.127.25454.158.127.2558,190
24554.158.128.0/1954.158.128.1 to 54.158.159.25454.158.159.2558,190
24654.158.160.0/1954.158.160.1 to 54.158.191.25454.158.191.2558,190
24754.158.192.0/1954.158.192.1 to 54.158.223.25454.158.223.2558,190
24854.158.224.0/1954.158.224.1 to 54.158.255.25454.158.255.2558,190
24954.159.0.0/1954.159.0.1 to 54.159.31.25454.159.31.2558,190
25054.159.32.0/1954.159.32.1 to 54.159.63.25454.159.63.2558,190
25154.159.64.0/1954.159.64.1 to 54.159.95.25454.159.95.2558,190
25254.159.96.0/1954.159.96.1 to 54.159.127.25454.159.127.2558,190
25354.159.128.0/1954.159.128.1 to 54.159.159.25454.159.159.2558,190
25454.159.160.0/1954.159.160.1 to 54.159.191.25454.159.191.2558,190
25554.159.192.0/1954.159.192.1 to 54.159.223.25454.159.223.2558,190
25654.159.224.0/1954.159.224.1 to 54.159.255.25454.159.255.2558,190

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.