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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.

Network69.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
69.0.0.0
Broadcast address
69.255.255.255
First usable
69.0.0.1
Last usable
69.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 45000000 · Integer 1157627904 to 1174405119
Reverse DNS zone
69.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000101..00000000.00000000.0000000069.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01000101..00000000.00000000.0000000069.0.0.0
Broadcast01000101..11111111.11111111.1111111169.255.255.255
Split into smaller subnets/19
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

69.0.0.0/8 makes 2,048 subnets of /19; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
169.0.0.0/1969.0.0.1 to 69.0.31.25469.0.31.2558,190
269.0.32.0/1969.0.32.1 to 69.0.63.25469.0.63.2558,190
369.0.64.0/1969.0.64.1 to 69.0.95.25469.0.95.2558,190
469.0.96.0/1969.0.96.1 to 69.0.127.25469.0.127.2558,190
569.0.128.0/1969.0.128.1 to 69.0.159.25469.0.159.2558,190
669.0.160.0/1969.0.160.1 to 69.0.191.25469.0.191.2558,190
769.0.192.0/1969.0.192.1 to 69.0.223.25469.0.223.2558,190
869.0.224.0/1969.0.224.1 to 69.0.255.25469.0.255.2558,190
969.1.0.0/1969.1.0.1 to 69.1.31.25469.1.31.2558,190
1069.1.32.0/1969.1.32.1 to 69.1.63.25469.1.63.2558,190
1169.1.64.0/1969.1.64.1 to 69.1.95.25469.1.95.2558,190
1269.1.96.0/1969.1.96.1 to 69.1.127.25469.1.127.2558,190
1369.1.128.0/1969.1.128.1 to 69.1.159.25469.1.159.2558,190
1469.1.160.0/1969.1.160.1 to 69.1.191.25469.1.191.2558,190
1569.1.192.0/1969.1.192.1 to 69.1.223.25469.1.223.2558,190
1669.1.224.0/1969.1.224.1 to 69.1.255.25469.1.255.2558,190
1769.2.0.0/1969.2.0.1 to 69.2.31.25469.2.31.2558,190
1869.2.32.0/1969.2.32.1 to 69.2.63.25469.2.63.2558,190
1969.2.64.0/1969.2.64.1 to 69.2.95.25469.2.95.2558,190
2069.2.96.0/1969.2.96.1 to 69.2.127.25469.2.127.2558,190
2169.2.128.0/1969.2.128.1 to 69.2.159.25469.2.159.2558,190
2269.2.160.0/1969.2.160.1 to 69.2.191.25469.2.191.2558,190
2369.2.192.0/1969.2.192.1 to 69.2.223.25469.2.223.2558,190
2469.2.224.0/1969.2.224.1 to 69.2.255.25469.2.255.2558,190
2569.3.0.0/1969.3.0.1 to 69.3.31.25469.3.31.2558,190
2669.3.32.0/1969.3.32.1 to 69.3.63.25469.3.63.2558,190
2769.3.64.0/1969.3.64.1 to 69.3.95.25469.3.95.2558,190
2869.3.96.0/1969.3.96.1 to 69.3.127.25469.3.127.2558,190
2969.3.128.0/1969.3.128.1 to 69.3.159.25469.3.159.2558,190
3069.3.160.0/1969.3.160.1 to 69.3.191.25469.3.191.2558,190
3169.3.192.0/1969.3.192.1 to 69.3.223.25469.3.223.2558,190
3269.3.224.0/1969.3.224.1 to 69.3.255.25469.3.255.2558,190
3369.4.0.0/1969.4.0.1 to 69.4.31.25469.4.31.2558,190
3469.4.32.0/1969.4.32.1 to 69.4.63.25469.4.63.2558,190
3569.4.64.0/1969.4.64.1 to 69.4.95.25469.4.95.2558,190
3669.4.96.0/1969.4.96.1 to 69.4.127.25469.4.127.2558,190
3769.4.128.0/1969.4.128.1 to 69.4.159.25469.4.159.2558,190
3869.4.160.0/1969.4.160.1 to 69.4.191.25469.4.191.2558,190
3969.4.192.0/1969.4.192.1 to 69.4.223.25469.4.223.2558,190
4069.4.224.0/1969.4.224.1 to 69.4.255.25469.4.255.2558,190
4169.5.0.0/1969.5.0.1 to 69.5.31.25469.5.31.2558,190
4269.5.32.0/1969.5.32.1 to 69.5.63.25469.5.63.2558,190
4369.5.64.0/1969.5.64.1 to 69.5.95.25469.5.95.2558,190
4469.5.96.0/1969.5.96.1 to 69.5.127.25469.5.127.2558,190
4569.5.128.0/1969.5.128.1 to 69.5.159.25469.5.159.2558,190
4669.5.160.0/1969.5.160.1 to 69.5.191.25469.5.191.2558,190
4769.5.192.0/1969.5.192.1 to 69.5.223.25469.5.223.2558,190
4869.5.224.0/1969.5.224.1 to 69.5.255.25469.5.255.2558,190
4969.6.0.0/1969.6.0.1 to 69.6.31.25469.6.31.2558,190
5069.6.32.0/1969.6.32.1 to 69.6.63.25469.6.63.2558,190
5169.6.64.0/1969.6.64.1 to 69.6.95.25469.6.95.2558,190
5269.6.96.0/1969.6.96.1 to 69.6.127.25469.6.127.2558,190
5369.6.128.0/1969.6.128.1 to 69.6.159.25469.6.159.2558,190
5469.6.160.0/1969.6.160.1 to 69.6.191.25469.6.191.2558,190
5569.6.192.0/1969.6.192.1 to 69.6.223.25469.6.223.2558,190
5669.6.224.0/1969.6.224.1 to 69.6.255.25469.6.255.2558,190
5769.7.0.0/1969.7.0.1 to 69.7.31.25469.7.31.2558,190
5869.7.32.0/1969.7.32.1 to 69.7.63.25469.7.63.2558,190
5969.7.64.0/1969.7.64.1 to 69.7.95.25469.7.95.2558,190
6069.7.96.0/1969.7.96.1 to 69.7.127.25469.7.127.2558,190
6169.7.128.0/1969.7.128.1 to 69.7.159.25469.7.159.2558,190
6269.7.160.0/1969.7.160.1 to 69.7.191.25469.7.191.2558,190
6369.7.192.0/1969.7.192.1 to 69.7.223.25469.7.223.2558,190
6469.7.224.0/1969.7.224.1 to 69.7.255.25469.7.255.2558,190
6569.8.0.0/1969.8.0.1 to 69.8.31.25469.8.31.2558,190
6669.8.32.0/1969.8.32.1 to 69.8.63.25469.8.63.2558,190
6769.8.64.0/1969.8.64.1 to 69.8.95.25469.8.95.2558,190
6869.8.96.0/1969.8.96.1 to 69.8.127.25469.8.127.2558,190
6969.8.128.0/1969.8.128.1 to 69.8.159.25469.8.159.2558,190
7069.8.160.0/1969.8.160.1 to 69.8.191.25469.8.191.2558,190
7169.8.192.0/1969.8.192.1 to 69.8.223.25469.8.223.2558,190
7269.8.224.0/1969.8.224.1 to 69.8.255.25469.8.255.2558,190
7369.9.0.0/1969.9.0.1 to 69.9.31.25469.9.31.2558,190
7469.9.32.0/1969.9.32.1 to 69.9.63.25469.9.63.2558,190
7569.9.64.0/1969.9.64.1 to 69.9.95.25469.9.95.2558,190
7669.9.96.0/1969.9.96.1 to 69.9.127.25469.9.127.2558,190
7769.9.128.0/1969.9.128.1 to 69.9.159.25469.9.159.2558,190
7869.9.160.0/1969.9.160.1 to 69.9.191.25469.9.191.2558,190
7969.9.192.0/1969.9.192.1 to 69.9.223.25469.9.223.2558,190
8069.9.224.0/1969.9.224.1 to 69.9.255.25469.9.255.2558,190
8169.10.0.0/1969.10.0.1 to 69.10.31.25469.10.31.2558,190
8269.10.32.0/1969.10.32.1 to 69.10.63.25469.10.63.2558,190
8369.10.64.0/1969.10.64.1 to 69.10.95.25469.10.95.2558,190
8469.10.96.0/1969.10.96.1 to 69.10.127.25469.10.127.2558,190
8569.10.128.0/1969.10.128.1 to 69.10.159.25469.10.159.2558,190
8669.10.160.0/1969.10.160.1 to 69.10.191.25469.10.191.2558,190
8769.10.192.0/1969.10.192.1 to 69.10.223.25469.10.223.2558,190
8869.10.224.0/1969.10.224.1 to 69.10.255.25469.10.255.2558,190
8969.11.0.0/1969.11.0.1 to 69.11.31.25469.11.31.2558,190
9069.11.32.0/1969.11.32.1 to 69.11.63.25469.11.63.2558,190
9169.11.64.0/1969.11.64.1 to 69.11.95.25469.11.95.2558,190
9269.11.96.0/1969.11.96.1 to 69.11.127.25469.11.127.2558,190
9369.11.128.0/1969.11.128.1 to 69.11.159.25469.11.159.2558,190
9469.11.160.0/1969.11.160.1 to 69.11.191.25469.11.191.2558,190
9569.11.192.0/1969.11.192.1 to 69.11.223.25469.11.223.2558,190
9669.11.224.0/1969.11.224.1 to 69.11.255.25469.11.255.2558,190
9769.12.0.0/1969.12.0.1 to 69.12.31.25469.12.31.2558,190
9869.12.32.0/1969.12.32.1 to 69.12.63.25469.12.63.2558,190
9969.12.64.0/1969.12.64.1 to 69.12.95.25469.12.95.2558,190
10069.12.96.0/1969.12.96.1 to 69.12.127.25469.12.127.2558,190
10169.12.128.0/1969.12.128.1 to 69.12.159.25469.12.159.2558,190
10269.12.160.0/1969.12.160.1 to 69.12.191.25469.12.191.2558,190
10369.12.192.0/1969.12.192.1 to 69.12.223.25469.12.223.2558,190
10469.12.224.0/1969.12.224.1 to 69.12.255.25469.12.255.2558,190
10569.13.0.0/1969.13.0.1 to 69.13.31.25469.13.31.2558,190
10669.13.32.0/1969.13.32.1 to 69.13.63.25469.13.63.2558,190
10769.13.64.0/1969.13.64.1 to 69.13.95.25469.13.95.2558,190
10869.13.96.0/1969.13.96.1 to 69.13.127.25469.13.127.2558,190
10969.13.128.0/1969.13.128.1 to 69.13.159.25469.13.159.2558,190
11069.13.160.0/1969.13.160.1 to 69.13.191.25469.13.191.2558,190
11169.13.192.0/1969.13.192.1 to 69.13.223.25469.13.223.2558,190
11269.13.224.0/1969.13.224.1 to 69.13.255.25469.13.255.2558,190
11369.14.0.0/1969.14.0.1 to 69.14.31.25469.14.31.2558,190
11469.14.32.0/1969.14.32.1 to 69.14.63.25469.14.63.2558,190
11569.14.64.0/1969.14.64.1 to 69.14.95.25469.14.95.2558,190
11669.14.96.0/1969.14.96.1 to 69.14.127.25469.14.127.2558,190
11769.14.128.0/1969.14.128.1 to 69.14.159.25469.14.159.2558,190
11869.14.160.0/1969.14.160.1 to 69.14.191.25469.14.191.2558,190
11969.14.192.0/1969.14.192.1 to 69.14.223.25469.14.223.2558,190
12069.14.224.0/1969.14.224.1 to 69.14.255.25469.14.255.2558,190
12169.15.0.0/1969.15.0.1 to 69.15.31.25469.15.31.2558,190
12269.15.32.0/1969.15.32.1 to 69.15.63.25469.15.63.2558,190
12369.15.64.0/1969.15.64.1 to 69.15.95.25469.15.95.2558,190
12469.15.96.0/1969.15.96.1 to 69.15.127.25469.15.127.2558,190
12569.15.128.0/1969.15.128.1 to 69.15.159.25469.15.159.2558,190
12669.15.160.0/1969.15.160.1 to 69.15.191.25469.15.191.2558,190
12769.15.192.0/1969.15.192.1 to 69.15.223.25469.15.223.2558,190
12869.15.224.0/1969.15.224.1 to 69.15.255.25469.15.255.2558,190
12969.16.0.0/1969.16.0.1 to 69.16.31.25469.16.31.2558,190
13069.16.32.0/1969.16.32.1 to 69.16.63.25469.16.63.2558,190
13169.16.64.0/1969.16.64.1 to 69.16.95.25469.16.95.2558,190
13269.16.96.0/1969.16.96.1 to 69.16.127.25469.16.127.2558,190
13369.16.128.0/1969.16.128.1 to 69.16.159.25469.16.159.2558,190
13469.16.160.0/1969.16.160.1 to 69.16.191.25469.16.191.2558,190
13569.16.192.0/1969.16.192.1 to 69.16.223.25469.16.223.2558,190
13669.16.224.0/1969.16.224.1 to 69.16.255.25469.16.255.2558,190
13769.17.0.0/1969.17.0.1 to 69.17.31.25469.17.31.2558,190
13869.17.32.0/1969.17.32.1 to 69.17.63.25469.17.63.2558,190
13969.17.64.0/1969.17.64.1 to 69.17.95.25469.17.95.2558,190
14069.17.96.0/1969.17.96.1 to 69.17.127.25469.17.127.2558,190
14169.17.128.0/1969.17.128.1 to 69.17.159.25469.17.159.2558,190
14269.17.160.0/1969.17.160.1 to 69.17.191.25469.17.191.2558,190
14369.17.192.0/1969.17.192.1 to 69.17.223.25469.17.223.2558,190
14469.17.224.0/1969.17.224.1 to 69.17.255.25469.17.255.2558,190
14569.18.0.0/1969.18.0.1 to 69.18.31.25469.18.31.2558,190
14669.18.32.0/1969.18.32.1 to 69.18.63.25469.18.63.2558,190
14769.18.64.0/1969.18.64.1 to 69.18.95.25469.18.95.2558,190
14869.18.96.0/1969.18.96.1 to 69.18.127.25469.18.127.2558,190
14969.18.128.0/1969.18.128.1 to 69.18.159.25469.18.159.2558,190
15069.18.160.0/1969.18.160.1 to 69.18.191.25469.18.191.2558,190
15169.18.192.0/1969.18.192.1 to 69.18.223.25469.18.223.2558,190
15269.18.224.0/1969.18.224.1 to 69.18.255.25469.18.255.2558,190
15369.19.0.0/1969.19.0.1 to 69.19.31.25469.19.31.2558,190
15469.19.32.0/1969.19.32.1 to 69.19.63.25469.19.63.2558,190
15569.19.64.0/1969.19.64.1 to 69.19.95.25469.19.95.2558,190
15669.19.96.0/1969.19.96.1 to 69.19.127.25469.19.127.2558,190
15769.19.128.0/1969.19.128.1 to 69.19.159.25469.19.159.2558,190
15869.19.160.0/1969.19.160.1 to 69.19.191.25469.19.191.2558,190
15969.19.192.0/1969.19.192.1 to 69.19.223.25469.19.223.2558,190
16069.19.224.0/1969.19.224.1 to 69.19.255.25469.19.255.2558,190
16169.20.0.0/1969.20.0.1 to 69.20.31.25469.20.31.2558,190
16269.20.32.0/1969.20.32.1 to 69.20.63.25469.20.63.2558,190
16369.20.64.0/1969.20.64.1 to 69.20.95.25469.20.95.2558,190
16469.20.96.0/1969.20.96.1 to 69.20.127.25469.20.127.2558,190
16569.20.128.0/1969.20.128.1 to 69.20.159.25469.20.159.2558,190
16669.20.160.0/1969.20.160.1 to 69.20.191.25469.20.191.2558,190
16769.20.192.0/1969.20.192.1 to 69.20.223.25469.20.223.2558,190
16869.20.224.0/1969.20.224.1 to 69.20.255.25469.20.255.2558,190
16969.21.0.0/1969.21.0.1 to 69.21.31.25469.21.31.2558,190
17069.21.32.0/1969.21.32.1 to 69.21.63.25469.21.63.2558,190
17169.21.64.0/1969.21.64.1 to 69.21.95.25469.21.95.2558,190
17269.21.96.0/1969.21.96.1 to 69.21.127.25469.21.127.2558,190
17369.21.128.0/1969.21.128.1 to 69.21.159.25469.21.159.2558,190
17469.21.160.0/1969.21.160.1 to 69.21.191.25469.21.191.2558,190
17569.21.192.0/1969.21.192.1 to 69.21.223.25469.21.223.2558,190
17669.21.224.0/1969.21.224.1 to 69.21.255.25469.21.255.2558,190
17769.22.0.0/1969.22.0.1 to 69.22.31.25469.22.31.2558,190
17869.22.32.0/1969.22.32.1 to 69.22.63.25469.22.63.2558,190
17969.22.64.0/1969.22.64.1 to 69.22.95.25469.22.95.2558,190
18069.22.96.0/1969.22.96.1 to 69.22.127.25469.22.127.2558,190
18169.22.128.0/1969.22.128.1 to 69.22.159.25469.22.159.2558,190
18269.22.160.0/1969.22.160.1 to 69.22.191.25469.22.191.2558,190
18369.22.192.0/1969.22.192.1 to 69.22.223.25469.22.223.2558,190
18469.22.224.0/1969.22.224.1 to 69.22.255.25469.22.255.2558,190
18569.23.0.0/1969.23.0.1 to 69.23.31.25469.23.31.2558,190
18669.23.32.0/1969.23.32.1 to 69.23.63.25469.23.63.2558,190
18769.23.64.0/1969.23.64.1 to 69.23.95.25469.23.95.2558,190
18869.23.96.0/1969.23.96.1 to 69.23.127.25469.23.127.2558,190
18969.23.128.0/1969.23.128.1 to 69.23.159.25469.23.159.2558,190
19069.23.160.0/1969.23.160.1 to 69.23.191.25469.23.191.2558,190
19169.23.192.0/1969.23.192.1 to 69.23.223.25469.23.223.2558,190
19269.23.224.0/1969.23.224.1 to 69.23.255.25469.23.255.2558,190
19369.24.0.0/1969.24.0.1 to 69.24.31.25469.24.31.2558,190
19469.24.32.0/1969.24.32.1 to 69.24.63.25469.24.63.2558,190
19569.24.64.0/1969.24.64.1 to 69.24.95.25469.24.95.2558,190
19669.24.96.0/1969.24.96.1 to 69.24.127.25469.24.127.2558,190
19769.24.128.0/1969.24.128.1 to 69.24.159.25469.24.159.2558,190
19869.24.160.0/1969.24.160.1 to 69.24.191.25469.24.191.2558,190
19969.24.192.0/1969.24.192.1 to 69.24.223.25469.24.223.2558,190
20069.24.224.0/1969.24.224.1 to 69.24.255.25469.24.255.2558,190
20169.25.0.0/1969.25.0.1 to 69.25.31.25469.25.31.2558,190
20269.25.32.0/1969.25.32.1 to 69.25.63.25469.25.63.2558,190
20369.25.64.0/1969.25.64.1 to 69.25.95.25469.25.95.2558,190
20469.25.96.0/1969.25.96.1 to 69.25.127.25469.25.127.2558,190
20569.25.128.0/1969.25.128.1 to 69.25.159.25469.25.159.2558,190
20669.25.160.0/1969.25.160.1 to 69.25.191.25469.25.191.2558,190
20769.25.192.0/1969.25.192.1 to 69.25.223.25469.25.223.2558,190
20869.25.224.0/1969.25.224.1 to 69.25.255.25469.25.255.2558,190
20969.26.0.0/1969.26.0.1 to 69.26.31.25469.26.31.2558,190
21069.26.32.0/1969.26.32.1 to 69.26.63.25469.26.63.2558,190
21169.26.64.0/1969.26.64.1 to 69.26.95.25469.26.95.2558,190
21269.26.96.0/1969.26.96.1 to 69.26.127.25469.26.127.2558,190
21369.26.128.0/1969.26.128.1 to 69.26.159.25469.26.159.2558,190
21469.26.160.0/1969.26.160.1 to 69.26.191.25469.26.191.2558,190
21569.26.192.0/1969.26.192.1 to 69.26.223.25469.26.223.2558,190
21669.26.224.0/1969.26.224.1 to 69.26.255.25469.26.255.2558,190
21769.27.0.0/1969.27.0.1 to 69.27.31.25469.27.31.2558,190
21869.27.32.0/1969.27.32.1 to 69.27.63.25469.27.63.2558,190
21969.27.64.0/1969.27.64.1 to 69.27.95.25469.27.95.2558,190
22069.27.96.0/1969.27.96.1 to 69.27.127.25469.27.127.2558,190
22169.27.128.0/1969.27.128.1 to 69.27.159.25469.27.159.2558,190
22269.27.160.0/1969.27.160.1 to 69.27.191.25469.27.191.2558,190
22369.27.192.0/1969.27.192.1 to 69.27.223.25469.27.223.2558,190
22469.27.224.0/1969.27.224.1 to 69.27.255.25469.27.255.2558,190
22569.28.0.0/1969.28.0.1 to 69.28.31.25469.28.31.2558,190
22669.28.32.0/1969.28.32.1 to 69.28.63.25469.28.63.2558,190
22769.28.64.0/1969.28.64.1 to 69.28.95.25469.28.95.2558,190
22869.28.96.0/1969.28.96.1 to 69.28.127.25469.28.127.2558,190
22969.28.128.0/1969.28.128.1 to 69.28.159.25469.28.159.2558,190
23069.28.160.0/1969.28.160.1 to 69.28.191.25469.28.191.2558,190
23169.28.192.0/1969.28.192.1 to 69.28.223.25469.28.223.2558,190
23269.28.224.0/1969.28.224.1 to 69.28.255.25469.28.255.2558,190
23369.29.0.0/1969.29.0.1 to 69.29.31.25469.29.31.2558,190
23469.29.32.0/1969.29.32.1 to 69.29.63.25469.29.63.2558,190
23569.29.64.0/1969.29.64.1 to 69.29.95.25469.29.95.2558,190
23669.29.96.0/1969.29.96.1 to 69.29.127.25469.29.127.2558,190
23769.29.128.0/1969.29.128.1 to 69.29.159.25469.29.159.2558,190
23869.29.160.0/1969.29.160.1 to 69.29.191.25469.29.191.2558,190
23969.29.192.0/1969.29.192.1 to 69.29.223.25469.29.223.2558,190
24069.29.224.0/1969.29.224.1 to 69.29.255.25469.29.255.2558,190
24169.30.0.0/1969.30.0.1 to 69.30.31.25469.30.31.2558,190
24269.30.32.0/1969.30.32.1 to 69.30.63.25469.30.63.2558,190
24369.30.64.0/1969.30.64.1 to 69.30.95.25469.30.95.2558,190
24469.30.96.0/1969.30.96.1 to 69.30.127.25469.30.127.2558,190
24569.30.128.0/1969.30.128.1 to 69.30.159.25469.30.159.2558,190
24669.30.160.0/1969.30.160.1 to 69.30.191.25469.30.191.2558,190
24769.30.192.0/1969.30.192.1 to 69.30.223.25469.30.223.2558,190
24869.30.224.0/1969.30.224.1 to 69.30.255.25469.30.255.2558,190
24969.31.0.0/1969.31.0.1 to 69.31.31.25469.31.31.2558,190
25069.31.32.0/1969.31.32.1 to 69.31.63.25469.31.63.2558,190
25169.31.64.0/1969.31.64.1 to 69.31.95.25469.31.95.2558,190
25269.31.96.0/1969.31.96.1 to 69.31.127.25469.31.127.2558,190
25369.31.128.0/1969.31.128.1 to 69.31.159.25469.31.159.2558,190
25469.31.160.0/1969.31.160.1 to 69.31.191.25469.31.191.2558,190
25569.31.192.0/1969.31.192.1 to 69.31.223.25469.31.223.2558,190
25669.31.224.0/1969.31.224.1 to 69.31.255.25469.31.255.2558,190

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.