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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.

Network35.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
35.0.0.0
Broadcast address
35.255.255.255
First usable
35.0.0.1
Last usable
35.255.255.254
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 23000000 · Integer 587202560 to 603979775
Reverse DNS zone
35.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00100011..00000000.00000000.0000000035.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00100011..00000000.00000000.0000000035.0.0.0
Broadcast00100011..11111111.11111111.1111111135.255.255.255
Split into smaller subnets/18
/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)

35.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
135.0.0.0/1835.0.0.1 to 35.0.63.25435.0.63.25516,382
235.0.64.0/1835.0.64.1 to 35.0.127.25435.0.127.25516,382
335.0.128.0/1835.0.128.1 to 35.0.191.25435.0.191.25516,382
435.0.192.0/1835.0.192.1 to 35.0.255.25435.0.255.25516,382
535.1.0.0/1835.1.0.1 to 35.1.63.25435.1.63.25516,382
635.1.64.0/1835.1.64.1 to 35.1.127.25435.1.127.25516,382
735.1.128.0/1835.1.128.1 to 35.1.191.25435.1.191.25516,382
835.1.192.0/1835.1.192.1 to 35.1.255.25435.1.255.25516,382
935.2.0.0/1835.2.0.1 to 35.2.63.25435.2.63.25516,382
1035.2.64.0/1835.2.64.1 to 35.2.127.25435.2.127.25516,382
1135.2.128.0/1835.2.128.1 to 35.2.191.25435.2.191.25516,382
1235.2.192.0/1835.2.192.1 to 35.2.255.25435.2.255.25516,382
1335.3.0.0/1835.3.0.1 to 35.3.63.25435.3.63.25516,382
1435.3.64.0/1835.3.64.1 to 35.3.127.25435.3.127.25516,382
1535.3.128.0/1835.3.128.1 to 35.3.191.25435.3.191.25516,382
1635.3.192.0/1835.3.192.1 to 35.3.255.25435.3.255.25516,382
1735.4.0.0/1835.4.0.1 to 35.4.63.25435.4.63.25516,382
1835.4.64.0/1835.4.64.1 to 35.4.127.25435.4.127.25516,382
1935.4.128.0/1835.4.128.1 to 35.4.191.25435.4.191.25516,382
2035.4.192.0/1835.4.192.1 to 35.4.255.25435.4.255.25516,382
2135.5.0.0/1835.5.0.1 to 35.5.63.25435.5.63.25516,382
2235.5.64.0/1835.5.64.1 to 35.5.127.25435.5.127.25516,382
2335.5.128.0/1835.5.128.1 to 35.5.191.25435.5.191.25516,382
2435.5.192.0/1835.5.192.1 to 35.5.255.25435.5.255.25516,382
2535.6.0.0/1835.6.0.1 to 35.6.63.25435.6.63.25516,382
2635.6.64.0/1835.6.64.1 to 35.6.127.25435.6.127.25516,382
2735.6.128.0/1835.6.128.1 to 35.6.191.25435.6.191.25516,382
2835.6.192.0/1835.6.192.1 to 35.6.255.25435.6.255.25516,382
2935.7.0.0/1835.7.0.1 to 35.7.63.25435.7.63.25516,382
3035.7.64.0/1835.7.64.1 to 35.7.127.25435.7.127.25516,382
3135.7.128.0/1835.7.128.1 to 35.7.191.25435.7.191.25516,382
3235.7.192.0/1835.7.192.1 to 35.7.255.25435.7.255.25516,382
3335.8.0.0/1835.8.0.1 to 35.8.63.25435.8.63.25516,382
3435.8.64.0/1835.8.64.1 to 35.8.127.25435.8.127.25516,382
3535.8.128.0/1835.8.128.1 to 35.8.191.25435.8.191.25516,382
3635.8.192.0/1835.8.192.1 to 35.8.255.25435.8.255.25516,382
3735.9.0.0/1835.9.0.1 to 35.9.63.25435.9.63.25516,382
3835.9.64.0/1835.9.64.1 to 35.9.127.25435.9.127.25516,382
3935.9.128.0/1835.9.128.1 to 35.9.191.25435.9.191.25516,382
4035.9.192.0/1835.9.192.1 to 35.9.255.25435.9.255.25516,382
4135.10.0.0/1835.10.0.1 to 35.10.63.25435.10.63.25516,382
4235.10.64.0/1835.10.64.1 to 35.10.127.25435.10.127.25516,382
4335.10.128.0/1835.10.128.1 to 35.10.191.25435.10.191.25516,382
4435.10.192.0/1835.10.192.1 to 35.10.255.25435.10.255.25516,382
4535.11.0.0/1835.11.0.1 to 35.11.63.25435.11.63.25516,382
4635.11.64.0/1835.11.64.1 to 35.11.127.25435.11.127.25516,382
4735.11.128.0/1835.11.128.1 to 35.11.191.25435.11.191.25516,382
4835.11.192.0/1835.11.192.1 to 35.11.255.25435.11.255.25516,382
4935.12.0.0/1835.12.0.1 to 35.12.63.25435.12.63.25516,382
5035.12.64.0/1835.12.64.1 to 35.12.127.25435.12.127.25516,382
5135.12.128.0/1835.12.128.1 to 35.12.191.25435.12.191.25516,382
5235.12.192.0/1835.12.192.1 to 35.12.255.25435.12.255.25516,382
5335.13.0.0/1835.13.0.1 to 35.13.63.25435.13.63.25516,382
5435.13.64.0/1835.13.64.1 to 35.13.127.25435.13.127.25516,382
5535.13.128.0/1835.13.128.1 to 35.13.191.25435.13.191.25516,382
5635.13.192.0/1835.13.192.1 to 35.13.255.25435.13.255.25516,382
5735.14.0.0/1835.14.0.1 to 35.14.63.25435.14.63.25516,382
5835.14.64.0/1835.14.64.1 to 35.14.127.25435.14.127.25516,382
5935.14.128.0/1835.14.128.1 to 35.14.191.25435.14.191.25516,382
6035.14.192.0/1835.14.192.1 to 35.14.255.25435.14.255.25516,382
6135.15.0.0/1835.15.0.1 to 35.15.63.25435.15.63.25516,382
6235.15.64.0/1835.15.64.1 to 35.15.127.25435.15.127.25516,382
6335.15.128.0/1835.15.128.1 to 35.15.191.25435.15.191.25516,382
6435.15.192.0/1835.15.192.1 to 35.15.255.25435.15.255.25516,382
6535.16.0.0/1835.16.0.1 to 35.16.63.25435.16.63.25516,382
6635.16.64.0/1835.16.64.1 to 35.16.127.25435.16.127.25516,382
6735.16.128.0/1835.16.128.1 to 35.16.191.25435.16.191.25516,382
6835.16.192.0/1835.16.192.1 to 35.16.255.25435.16.255.25516,382
6935.17.0.0/1835.17.0.1 to 35.17.63.25435.17.63.25516,382
7035.17.64.0/1835.17.64.1 to 35.17.127.25435.17.127.25516,382
7135.17.128.0/1835.17.128.1 to 35.17.191.25435.17.191.25516,382
7235.17.192.0/1835.17.192.1 to 35.17.255.25435.17.255.25516,382
7335.18.0.0/1835.18.0.1 to 35.18.63.25435.18.63.25516,382
7435.18.64.0/1835.18.64.1 to 35.18.127.25435.18.127.25516,382
7535.18.128.0/1835.18.128.1 to 35.18.191.25435.18.191.25516,382
7635.18.192.0/1835.18.192.1 to 35.18.255.25435.18.255.25516,382
7735.19.0.0/1835.19.0.1 to 35.19.63.25435.19.63.25516,382
7835.19.64.0/1835.19.64.1 to 35.19.127.25435.19.127.25516,382
7935.19.128.0/1835.19.128.1 to 35.19.191.25435.19.191.25516,382
8035.19.192.0/1835.19.192.1 to 35.19.255.25435.19.255.25516,382
8135.20.0.0/1835.20.0.1 to 35.20.63.25435.20.63.25516,382
8235.20.64.0/1835.20.64.1 to 35.20.127.25435.20.127.25516,382
8335.20.128.0/1835.20.128.1 to 35.20.191.25435.20.191.25516,382
8435.20.192.0/1835.20.192.1 to 35.20.255.25435.20.255.25516,382
8535.21.0.0/1835.21.0.1 to 35.21.63.25435.21.63.25516,382
8635.21.64.0/1835.21.64.1 to 35.21.127.25435.21.127.25516,382
8735.21.128.0/1835.21.128.1 to 35.21.191.25435.21.191.25516,382
8835.21.192.0/1835.21.192.1 to 35.21.255.25435.21.255.25516,382
8935.22.0.0/1835.22.0.1 to 35.22.63.25435.22.63.25516,382
9035.22.64.0/1835.22.64.1 to 35.22.127.25435.22.127.25516,382
9135.22.128.0/1835.22.128.1 to 35.22.191.25435.22.191.25516,382
9235.22.192.0/1835.22.192.1 to 35.22.255.25435.22.255.25516,382
9335.23.0.0/1835.23.0.1 to 35.23.63.25435.23.63.25516,382
9435.23.64.0/1835.23.64.1 to 35.23.127.25435.23.127.25516,382
9535.23.128.0/1835.23.128.1 to 35.23.191.25435.23.191.25516,382
9635.23.192.0/1835.23.192.1 to 35.23.255.25435.23.255.25516,382
9735.24.0.0/1835.24.0.1 to 35.24.63.25435.24.63.25516,382
9835.24.64.0/1835.24.64.1 to 35.24.127.25435.24.127.25516,382
9935.24.128.0/1835.24.128.1 to 35.24.191.25435.24.191.25516,382
10035.24.192.0/1835.24.192.1 to 35.24.255.25435.24.255.25516,382
10135.25.0.0/1835.25.0.1 to 35.25.63.25435.25.63.25516,382
10235.25.64.0/1835.25.64.1 to 35.25.127.25435.25.127.25516,382
10335.25.128.0/1835.25.128.1 to 35.25.191.25435.25.191.25516,382
10435.25.192.0/1835.25.192.1 to 35.25.255.25435.25.255.25516,382
10535.26.0.0/1835.26.0.1 to 35.26.63.25435.26.63.25516,382
10635.26.64.0/1835.26.64.1 to 35.26.127.25435.26.127.25516,382
10735.26.128.0/1835.26.128.1 to 35.26.191.25435.26.191.25516,382
10835.26.192.0/1835.26.192.1 to 35.26.255.25435.26.255.25516,382
10935.27.0.0/1835.27.0.1 to 35.27.63.25435.27.63.25516,382
11035.27.64.0/1835.27.64.1 to 35.27.127.25435.27.127.25516,382
11135.27.128.0/1835.27.128.1 to 35.27.191.25435.27.191.25516,382
11235.27.192.0/1835.27.192.1 to 35.27.255.25435.27.255.25516,382
11335.28.0.0/1835.28.0.1 to 35.28.63.25435.28.63.25516,382
11435.28.64.0/1835.28.64.1 to 35.28.127.25435.28.127.25516,382
11535.28.128.0/1835.28.128.1 to 35.28.191.25435.28.191.25516,382
11635.28.192.0/1835.28.192.1 to 35.28.255.25435.28.255.25516,382
11735.29.0.0/1835.29.0.1 to 35.29.63.25435.29.63.25516,382
11835.29.64.0/1835.29.64.1 to 35.29.127.25435.29.127.25516,382
11935.29.128.0/1835.29.128.1 to 35.29.191.25435.29.191.25516,382
12035.29.192.0/1835.29.192.1 to 35.29.255.25435.29.255.25516,382
12135.30.0.0/1835.30.0.1 to 35.30.63.25435.30.63.25516,382
12235.30.64.0/1835.30.64.1 to 35.30.127.25435.30.127.25516,382
12335.30.128.0/1835.30.128.1 to 35.30.191.25435.30.191.25516,382
12435.30.192.0/1835.30.192.1 to 35.30.255.25435.30.255.25516,382
12535.31.0.0/1835.31.0.1 to 35.31.63.25435.31.63.25516,382
12635.31.64.0/1835.31.64.1 to 35.31.127.25435.31.127.25516,382
12735.31.128.0/1835.31.128.1 to 35.31.191.25435.31.191.25516,382
12835.31.192.0/1835.31.192.1 to 35.31.255.25435.31.255.25516,382
12935.32.0.0/1835.32.0.1 to 35.32.63.25435.32.63.25516,382
13035.32.64.0/1835.32.64.1 to 35.32.127.25435.32.127.25516,382
13135.32.128.0/1835.32.128.1 to 35.32.191.25435.32.191.25516,382
13235.32.192.0/1835.32.192.1 to 35.32.255.25435.32.255.25516,382
13335.33.0.0/1835.33.0.1 to 35.33.63.25435.33.63.25516,382
13435.33.64.0/1835.33.64.1 to 35.33.127.25435.33.127.25516,382
13535.33.128.0/1835.33.128.1 to 35.33.191.25435.33.191.25516,382
13635.33.192.0/1835.33.192.1 to 35.33.255.25435.33.255.25516,382
13735.34.0.0/1835.34.0.1 to 35.34.63.25435.34.63.25516,382
13835.34.64.0/1835.34.64.1 to 35.34.127.25435.34.127.25516,382
13935.34.128.0/1835.34.128.1 to 35.34.191.25435.34.191.25516,382
14035.34.192.0/1835.34.192.1 to 35.34.255.25435.34.255.25516,382
14135.35.0.0/1835.35.0.1 to 35.35.63.25435.35.63.25516,382
14235.35.64.0/1835.35.64.1 to 35.35.127.25435.35.127.25516,382
14335.35.128.0/1835.35.128.1 to 35.35.191.25435.35.191.25516,382
14435.35.192.0/1835.35.192.1 to 35.35.255.25435.35.255.25516,382
14535.36.0.0/1835.36.0.1 to 35.36.63.25435.36.63.25516,382
14635.36.64.0/1835.36.64.1 to 35.36.127.25435.36.127.25516,382
14735.36.128.0/1835.36.128.1 to 35.36.191.25435.36.191.25516,382
14835.36.192.0/1835.36.192.1 to 35.36.255.25435.36.255.25516,382
14935.37.0.0/1835.37.0.1 to 35.37.63.25435.37.63.25516,382
15035.37.64.0/1835.37.64.1 to 35.37.127.25435.37.127.25516,382
15135.37.128.0/1835.37.128.1 to 35.37.191.25435.37.191.25516,382
15235.37.192.0/1835.37.192.1 to 35.37.255.25435.37.255.25516,382
15335.38.0.0/1835.38.0.1 to 35.38.63.25435.38.63.25516,382
15435.38.64.0/1835.38.64.1 to 35.38.127.25435.38.127.25516,382
15535.38.128.0/1835.38.128.1 to 35.38.191.25435.38.191.25516,382
15635.38.192.0/1835.38.192.1 to 35.38.255.25435.38.255.25516,382
15735.39.0.0/1835.39.0.1 to 35.39.63.25435.39.63.25516,382
15835.39.64.0/1835.39.64.1 to 35.39.127.25435.39.127.25516,382
15935.39.128.0/1835.39.128.1 to 35.39.191.25435.39.191.25516,382
16035.39.192.0/1835.39.192.1 to 35.39.255.25435.39.255.25516,382
16135.40.0.0/1835.40.0.1 to 35.40.63.25435.40.63.25516,382
16235.40.64.0/1835.40.64.1 to 35.40.127.25435.40.127.25516,382
16335.40.128.0/1835.40.128.1 to 35.40.191.25435.40.191.25516,382
16435.40.192.0/1835.40.192.1 to 35.40.255.25435.40.255.25516,382
16535.41.0.0/1835.41.0.1 to 35.41.63.25435.41.63.25516,382
16635.41.64.0/1835.41.64.1 to 35.41.127.25435.41.127.25516,382
16735.41.128.0/1835.41.128.1 to 35.41.191.25435.41.191.25516,382
16835.41.192.0/1835.41.192.1 to 35.41.255.25435.41.255.25516,382
16935.42.0.0/1835.42.0.1 to 35.42.63.25435.42.63.25516,382
17035.42.64.0/1835.42.64.1 to 35.42.127.25435.42.127.25516,382
17135.42.128.0/1835.42.128.1 to 35.42.191.25435.42.191.25516,382
17235.42.192.0/1835.42.192.1 to 35.42.255.25435.42.255.25516,382
17335.43.0.0/1835.43.0.1 to 35.43.63.25435.43.63.25516,382
17435.43.64.0/1835.43.64.1 to 35.43.127.25435.43.127.25516,382
17535.43.128.0/1835.43.128.1 to 35.43.191.25435.43.191.25516,382
17635.43.192.0/1835.43.192.1 to 35.43.255.25435.43.255.25516,382
17735.44.0.0/1835.44.0.1 to 35.44.63.25435.44.63.25516,382
17835.44.64.0/1835.44.64.1 to 35.44.127.25435.44.127.25516,382
17935.44.128.0/1835.44.128.1 to 35.44.191.25435.44.191.25516,382
18035.44.192.0/1835.44.192.1 to 35.44.255.25435.44.255.25516,382
18135.45.0.0/1835.45.0.1 to 35.45.63.25435.45.63.25516,382
18235.45.64.0/1835.45.64.1 to 35.45.127.25435.45.127.25516,382
18335.45.128.0/1835.45.128.1 to 35.45.191.25435.45.191.25516,382
18435.45.192.0/1835.45.192.1 to 35.45.255.25435.45.255.25516,382
18535.46.0.0/1835.46.0.1 to 35.46.63.25435.46.63.25516,382
18635.46.64.0/1835.46.64.1 to 35.46.127.25435.46.127.25516,382
18735.46.128.0/1835.46.128.1 to 35.46.191.25435.46.191.25516,382
18835.46.192.0/1835.46.192.1 to 35.46.255.25435.46.255.25516,382
18935.47.0.0/1835.47.0.1 to 35.47.63.25435.47.63.25516,382
19035.47.64.0/1835.47.64.1 to 35.47.127.25435.47.127.25516,382
19135.47.128.0/1835.47.128.1 to 35.47.191.25435.47.191.25516,382
19235.47.192.0/1835.47.192.1 to 35.47.255.25435.47.255.25516,382
19335.48.0.0/1835.48.0.1 to 35.48.63.25435.48.63.25516,382
19435.48.64.0/1835.48.64.1 to 35.48.127.25435.48.127.25516,382
19535.48.128.0/1835.48.128.1 to 35.48.191.25435.48.191.25516,382
19635.48.192.0/1835.48.192.1 to 35.48.255.25435.48.255.25516,382
19735.49.0.0/1835.49.0.1 to 35.49.63.25435.49.63.25516,382
19835.49.64.0/1835.49.64.1 to 35.49.127.25435.49.127.25516,382
19935.49.128.0/1835.49.128.1 to 35.49.191.25435.49.191.25516,382
20035.49.192.0/1835.49.192.1 to 35.49.255.25435.49.255.25516,382
20135.50.0.0/1835.50.0.1 to 35.50.63.25435.50.63.25516,382
20235.50.64.0/1835.50.64.1 to 35.50.127.25435.50.127.25516,382
20335.50.128.0/1835.50.128.1 to 35.50.191.25435.50.191.25516,382
20435.50.192.0/1835.50.192.1 to 35.50.255.25435.50.255.25516,382
20535.51.0.0/1835.51.0.1 to 35.51.63.25435.51.63.25516,382
20635.51.64.0/1835.51.64.1 to 35.51.127.25435.51.127.25516,382
20735.51.128.0/1835.51.128.1 to 35.51.191.25435.51.191.25516,382
20835.51.192.0/1835.51.192.1 to 35.51.255.25435.51.255.25516,382
20935.52.0.0/1835.52.0.1 to 35.52.63.25435.52.63.25516,382
21035.52.64.0/1835.52.64.1 to 35.52.127.25435.52.127.25516,382
21135.52.128.0/1835.52.128.1 to 35.52.191.25435.52.191.25516,382
21235.52.192.0/1835.52.192.1 to 35.52.255.25435.52.255.25516,382
21335.53.0.0/1835.53.0.1 to 35.53.63.25435.53.63.25516,382
21435.53.64.0/1835.53.64.1 to 35.53.127.25435.53.127.25516,382
21535.53.128.0/1835.53.128.1 to 35.53.191.25435.53.191.25516,382
21635.53.192.0/1835.53.192.1 to 35.53.255.25435.53.255.25516,382
21735.54.0.0/1835.54.0.1 to 35.54.63.25435.54.63.25516,382
21835.54.64.0/1835.54.64.1 to 35.54.127.25435.54.127.25516,382
21935.54.128.0/1835.54.128.1 to 35.54.191.25435.54.191.25516,382
22035.54.192.0/1835.54.192.1 to 35.54.255.25435.54.255.25516,382
22135.55.0.0/1835.55.0.1 to 35.55.63.25435.55.63.25516,382
22235.55.64.0/1835.55.64.1 to 35.55.127.25435.55.127.25516,382
22335.55.128.0/1835.55.128.1 to 35.55.191.25435.55.191.25516,382
22435.55.192.0/1835.55.192.1 to 35.55.255.25435.55.255.25516,382
22535.56.0.0/1835.56.0.1 to 35.56.63.25435.56.63.25516,382
22635.56.64.0/1835.56.64.1 to 35.56.127.25435.56.127.25516,382
22735.56.128.0/1835.56.128.1 to 35.56.191.25435.56.191.25516,382
22835.56.192.0/1835.56.192.1 to 35.56.255.25435.56.255.25516,382
22935.57.0.0/1835.57.0.1 to 35.57.63.25435.57.63.25516,382
23035.57.64.0/1835.57.64.1 to 35.57.127.25435.57.127.25516,382
23135.57.128.0/1835.57.128.1 to 35.57.191.25435.57.191.25516,382
23235.57.192.0/1835.57.192.1 to 35.57.255.25435.57.255.25516,382
23335.58.0.0/1835.58.0.1 to 35.58.63.25435.58.63.25516,382
23435.58.64.0/1835.58.64.1 to 35.58.127.25435.58.127.25516,382
23535.58.128.0/1835.58.128.1 to 35.58.191.25435.58.191.25516,382
23635.58.192.0/1835.58.192.1 to 35.58.255.25435.58.255.25516,382
23735.59.0.0/1835.59.0.1 to 35.59.63.25435.59.63.25516,382
23835.59.64.0/1835.59.64.1 to 35.59.127.25435.59.127.25516,382
23935.59.128.0/1835.59.128.1 to 35.59.191.25435.59.191.25516,382
24035.59.192.0/1835.59.192.1 to 35.59.255.25435.59.255.25516,382
24135.60.0.0/1835.60.0.1 to 35.60.63.25435.60.63.25516,382
24235.60.64.0/1835.60.64.1 to 35.60.127.25435.60.127.25516,382
24335.60.128.0/1835.60.128.1 to 35.60.191.25435.60.191.25516,382
24435.60.192.0/1835.60.192.1 to 35.60.255.25435.60.255.25516,382
24535.61.0.0/1835.61.0.1 to 35.61.63.25435.61.63.25516,382
24635.61.64.0/1835.61.64.1 to 35.61.127.25435.61.127.25516,382
24735.61.128.0/1835.61.128.1 to 35.61.191.25435.61.191.25516,382
24835.61.192.0/1835.61.192.1 to 35.61.255.25435.61.255.25516,382
24935.62.0.0/1835.62.0.1 to 35.62.63.25435.62.63.25516,382
25035.62.64.0/1835.62.64.1 to 35.62.127.25435.62.127.25516,382
25135.62.128.0/1835.62.128.1 to 35.62.191.25435.62.191.25516,382
25235.62.192.0/1835.62.192.1 to 35.62.255.25435.62.255.25516,382
25335.63.0.0/1835.63.0.1 to 35.63.63.25435.63.63.25516,382
25435.63.64.0/1835.63.64.1 to 35.63.127.25435.63.127.25516,382
25535.63.128.0/1835.63.128.1 to 35.63.191.25435.63.191.25516,382
25635.63.192.0/1835.63.192.1 to 35.63.255.25435.63.255.25516,382

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.