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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.

Network76.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
76.0.0.0
Broadcast address
76.255.255.255
First usable
76.0.0.1
Last usable
76.255.255.254
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 4C000000 · Integer 1275068416 to 1291845631
Reverse DNS zone
76.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001100..00000000.00000000.0000000076.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01001100..00000000.00000000.0000000076.0.0.0
Broadcast01001100..11111111.11111111.1111111176.255.255.255
Split into smaller subnets/20
/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)

76.0.0.0/8 makes 4,096 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
176.0.0.0/2076.0.0.1 to 76.0.15.25476.0.15.2554,094
276.0.16.0/2076.0.16.1 to 76.0.31.25476.0.31.2554,094
376.0.32.0/2076.0.32.1 to 76.0.47.25476.0.47.2554,094
476.0.48.0/2076.0.48.1 to 76.0.63.25476.0.63.2554,094
576.0.64.0/2076.0.64.1 to 76.0.79.25476.0.79.2554,094
676.0.80.0/2076.0.80.1 to 76.0.95.25476.0.95.2554,094
776.0.96.0/2076.0.96.1 to 76.0.111.25476.0.111.2554,094
876.0.112.0/2076.0.112.1 to 76.0.127.25476.0.127.2554,094
976.0.128.0/2076.0.128.1 to 76.0.143.25476.0.143.2554,094
1076.0.144.0/2076.0.144.1 to 76.0.159.25476.0.159.2554,094
1176.0.160.0/2076.0.160.1 to 76.0.175.25476.0.175.2554,094
1276.0.176.0/2076.0.176.1 to 76.0.191.25476.0.191.2554,094
1376.0.192.0/2076.0.192.1 to 76.0.207.25476.0.207.2554,094
1476.0.208.0/2076.0.208.1 to 76.0.223.25476.0.223.2554,094
1576.0.224.0/2076.0.224.1 to 76.0.239.25476.0.239.2554,094
1676.0.240.0/2076.0.240.1 to 76.0.255.25476.0.255.2554,094
1776.1.0.0/2076.1.0.1 to 76.1.15.25476.1.15.2554,094
1876.1.16.0/2076.1.16.1 to 76.1.31.25476.1.31.2554,094
1976.1.32.0/2076.1.32.1 to 76.1.47.25476.1.47.2554,094
2076.1.48.0/2076.1.48.1 to 76.1.63.25476.1.63.2554,094
2176.1.64.0/2076.1.64.1 to 76.1.79.25476.1.79.2554,094
2276.1.80.0/2076.1.80.1 to 76.1.95.25476.1.95.2554,094
2376.1.96.0/2076.1.96.1 to 76.1.111.25476.1.111.2554,094
2476.1.112.0/2076.1.112.1 to 76.1.127.25476.1.127.2554,094
2576.1.128.0/2076.1.128.1 to 76.1.143.25476.1.143.2554,094
2676.1.144.0/2076.1.144.1 to 76.1.159.25476.1.159.2554,094
2776.1.160.0/2076.1.160.1 to 76.1.175.25476.1.175.2554,094
2876.1.176.0/2076.1.176.1 to 76.1.191.25476.1.191.2554,094
2976.1.192.0/2076.1.192.1 to 76.1.207.25476.1.207.2554,094
3076.1.208.0/2076.1.208.1 to 76.1.223.25476.1.223.2554,094
3176.1.224.0/2076.1.224.1 to 76.1.239.25476.1.239.2554,094
3276.1.240.0/2076.1.240.1 to 76.1.255.25476.1.255.2554,094
3376.2.0.0/2076.2.0.1 to 76.2.15.25476.2.15.2554,094
3476.2.16.0/2076.2.16.1 to 76.2.31.25476.2.31.2554,094
3576.2.32.0/2076.2.32.1 to 76.2.47.25476.2.47.2554,094
3676.2.48.0/2076.2.48.1 to 76.2.63.25476.2.63.2554,094
3776.2.64.0/2076.2.64.1 to 76.2.79.25476.2.79.2554,094
3876.2.80.0/2076.2.80.1 to 76.2.95.25476.2.95.2554,094
3976.2.96.0/2076.2.96.1 to 76.2.111.25476.2.111.2554,094
4076.2.112.0/2076.2.112.1 to 76.2.127.25476.2.127.2554,094
4176.2.128.0/2076.2.128.1 to 76.2.143.25476.2.143.2554,094
4276.2.144.0/2076.2.144.1 to 76.2.159.25476.2.159.2554,094
4376.2.160.0/2076.2.160.1 to 76.2.175.25476.2.175.2554,094
4476.2.176.0/2076.2.176.1 to 76.2.191.25476.2.191.2554,094
4576.2.192.0/2076.2.192.1 to 76.2.207.25476.2.207.2554,094
4676.2.208.0/2076.2.208.1 to 76.2.223.25476.2.223.2554,094
4776.2.224.0/2076.2.224.1 to 76.2.239.25476.2.239.2554,094
4876.2.240.0/2076.2.240.1 to 76.2.255.25476.2.255.2554,094
4976.3.0.0/2076.3.0.1 to 76.3.15.25476.3.15.2554,094
5076.3.16.0/2076.3.16.1 to 76.3.31.25476.3.31.2554,094
5176.3.32.0/2076.3.32.1 to 76.3.47.25476.3.47.2554,094
5276.3.48.0/2076.3.48.1 to 76.3.63.25476.3.63.2554,094
5376.3.64.0/2076.3.64.1 to 76.3.79.25476.3.79.2554,094
5476.3.80.0/2076.3.80.1 to 76.3.95.25476.3.95.2554,094
5576.3.96.0/2076.3.96.1 to 76.3.111.25476.3.111.2554,094
5676.3.112.0/2076.3.112.1 to 76.3.127.25476.3.127.2554,094
5776.3.128.0/2076.3.128.1 to 76.3.143.25476.3.143.2554,094
5876.3.144.0/2076.3.144.1 to 76.3.159.25476.3.159.2554,094
5976.3.160.0/2076.3.160.1 to 76.3.175.25476.3.175.2554,094
6076.3.176.0/2076.3.176.1 to 76.3.191.25476.3.191.2554,094
6176.3.192.0/2076.3.192.1 to 76.3.207.25476.3.207.2554,094
6276.3.208.0/2076.3.208.1 to 76.3.223.25476.3.223.2554,094
6376.3.224.0/2076.3.224.1 to 76.3.239.25476.3.239.2554,094
6476.3.240.0/2076.3.240.1 to 76.3.255.25476.3.255.2554,094
6576.4.0.0/2076.4.0.1 to 76.4.15.25476.4.15.2554,094
6676.4.16.0/2076.4.16.1 to 76.4.31.25476.4.31.2554,094
6776.4.32.0/2076.4.32.1 to 76.4.47.25476.4.47.2554,094
6876.4.48.0/2076.4.48.1 to 76.4.63.25476.4.63.2554,094
6976.4.64.0/2076.4.64.1 to 76.4.79.25476.4.79.2554,094
7076.4.80.0/2076.4.80.1 to 76.4.95.25476.4.95.2554,094
7176.4.96.0/2076.4.96.1 to 76.4.111.25476.4.111.2554,094
7276.4.112.0/2076.4.112.1 to 76.4.127.25476.4.127.2554,094
7376.4.128.0/2076.4.128.1 to 76.4.143.25476.4.143.2554,094
7476.4.144.0/2076.4.144.1 to 76.4.159.25476.4.159.2554,094
7576.4.160.0/2076.4.160.1 to 76.4.175.25476.4.175.2554,094
7676.4.176.0/2076.4.176.1 to 76.4.191.25476.4.191.2554,094
7776.4.192.0/2076.4.192.1 to 76.4.207.25476.4.207.2554,094
7876.4.208.0/2076.4.208.1 to 76.4.223.25476.4.223.2554,094
7976.4.224.0/2076.4.224.1 to 76.4.239.25476.4.239.2554,094
8076.4.240.0/2076.4.240.1 to 76.4.255.25476.4.255.2554,094
8176.5.0.0/2076.5.0.1 to 76.5.15.25476.5.15.2554,094
8276.5.16.0/2076.5.16.1 to 76.5.31.25476.5.31.2554,094
8376.5.32.0/2076.5.32.1 to 76.5.47.25476.5.47.2554,094
8476.5.48.0/2076.5.48.1 to 76.5.63.25476.5.63.2554,094
8576.5.64.0/2076.5.64.1 to 76.5.79.25476.5.79.2554,094
8676.5.80.0/2076.5.80.1 to 76.5.95.25476.5.95.2554,094
8776.5.96.0/2076.5.96.1 to 76.5.111.25476.5.111.2554,094
8876.5.112.0/2076.5.112.1 to 76.5.127.25476.5.127.2554,094
8976.5.128.0/2076.5.128.1 to 76.5.143.25476.5.143.2554,094
9076.5.144.0/2076.5.144.1 to 76.5.159.25476.5.159.2554,094
9176.5.160.0/2076.5.160.1 to 76.5.175.25476.5.175.2554,094
9276.5.176.0/2076.5.176.1 to 76.5.191.25476.5.191.2554,094
9376.5.192.0/2076.5.192.1 to 76.5.207.25476.5.207.2554,094
9476.5.208.0/2076.5.208.1 to 76.5.223.25476.5.223.2554,094
9576.5.224.0/2076.5.224.1 to 76.5.239.25476.5.239.2554,094
9676.5.240.0/2076.5.240.1 to 76.5.255.25476.5.255.2554,094
9776.6.0.0/2076.6.0.1 to 76.6.15.25476.6.15.2554,094
9876.6.16.0/2076.6.16.1 to 76.6.31.25476.6.31.2554,094
9976.6.32.0/2076.6.32.1 to 76.6.47.25476.6.47.2554,094
10076.6.48.0/2076.6.48.1 to 76.6.63.25476.6.63.2554,094
10176.6.64.0/2076.6.64.1 to 76.6.79.25476.6.79.2554,094
10276.6.80.0/2076.6.80.1 to 76.6.95.25476.6.95.2554,094
10376.6.96.0/2076.6.96.1 to 76.6.111.25476.6.111.2554,094
10476.6.112.0/2076.6.112.1 to 76.6.127.25476.6.127.2554,094
10576.6.128.0/2076.6.128.1 to 76.6.143.25476.6.143.2554,094
10676.6.144.0/2076.6.144.1 to 76.6.159.25476.6.159.2554,094
10776.6.160.0/2076.6.160.1 to 76.6.175.25476.6.175.2554,094
10876.6.176.0/2076.6.176.1 to 76.6.191.25476.6.191.2554,094
10976.6.192.0/2076.6.192.1 to 76.6.207.25476.6.207.2554,094
11076.6.208.0/2076.6.208.1 to 76.6.223.25476.6.223.2554,094
11176.6.224.0/2076.6.224.1 to 76.6.239.25476.6.239.2554,094
11276.6.240.0/2076.6.240.1 to 76.6.255.25476.6.255.2554,094
11376.7.0.0/2076.7.0.1 to 76.7.15.25476.7.15.2554,094
11476.7.16.0/2076.7.16.1 to 76.7.31.25476.7.31.2554,094
11576.7.32.0/2076.7.32.1 to 76.7.47.25476.7.47.2554,094
11676.7.48.0/2076.7.48.1 to 76.7.63.25476.7.63.2554,094
11776.7.64.0/2076.7.64.1 to 76.7.79.25476.7.79.2554,094
11876.7.80.0/2076.7.80.1 to 76.7.95.25476.7.95.2554,094
11976.7.96.0/2076.7.96.1 to 76.7.111.25476.7.111.2554,094
12076.7.112.0/2076.7.112.1 to 76.7.127.25476.7.127.2554,094
12176.7.128.0/2076.7.128.1 to 76.7.143.25476.7.143.2554,094
12276.7.144.0/2076.7.144.1 to 76.7.159.25476.7.159.2554,094
12376.7.160.0/2076.7.160.1 to 76.7.175.25476.7.175.2554,094
12476.7.176.0/2076.7.176.1 to 76.7.191.25476.7.191.2554,094
12576.7.192.0/2076.7.192.1 to 76.7.207.25476.7.207.2554,094
12676.7.208.0/2076.7.208.1 to 76.7.223.25476.7.223.2554,094
12776.7.224.0/2076.7.224.1 to 76.7.239.25476.7.239.2554,094
12876.7.240.0/2076.7.240.1 to 76.7.255.25476.7.255.2554,094
12976.8.0.0/2076.8.0.1 to 76.8.15.25476.8.15.2554,094
13076.8.16.0/2076.8.16.1 to 76.8.31.25476.8.31.2554,094
13176.8.32.0/2076.8.32.1 to 76.8.47.25476.8.47.2554,094
13276.8.48.0/2076.8.48.1 to 76.8.63.25476.8.63.2554,094
13376.8.64.0/2076.8.64.1 to 76.8.79.25476.8.79.2554,094
13476.8.80.0/2076.8.80.1 to 76.8.95.25476.8.95.2554,094
13576.8.96.0/2076.8.96.1 to 76.8.111.25476.8.111.2554,094
13676.8.112.0/2076.8.112.1 to 76.8.127.25476.8.127.2554,094
13776.8.128.0/2076.8.128.1 to 76.8.143.25476.8.143.2554,094
13876.8.144.0/2076.8.144.1 to 76.8.159.25476.8.159.2554,094
13976.8.160.0/2076.8.160.1 to 76.8.175.25476.8.175.2554,094
14076.8.176.0/2076.8.176.1 to 76.8.191.25476.8.191.2554,094
14176.8.192.0/2076.8.192.1 to 76.8.207.25476.8.207.2554,094
14276.8.208.0/2076.8.208.1 to 76.8.223.25476.8.223.2554,094
14376.8.224.0/2076.8.224.1 to 76.8.239.25476.8.239.2554,094
14476.8.240.0/2076.8.240.1 to 76.8.255.25476.8.255.2554,094
14576.9.0.0/2076.9.0.1 to 76.9.15.25476.9.15.2554,094
14676.9.16.0/2076.9.16.1 to 76.9.31.25476.9.31.2554,094
14776.9.32.0/2076.9.32.1 to 76.9.47.25476.9.47.2554,094
14876.9.48.0/2076.9.48.1 to 76.9.63.25476.9.63.2554,094
14976.9.64.0/2076.9.64.1 to 76.9.79.25476.9.79.2554,094
15076.9.80.0/2076.9.80.1 to 76.9.95.25476.9.95.2554,094
15176.9.96.0/2076.9.96.1 to 76.9.111.25476.9.111.2554,094
15276.9.112.0/2076.9.112.1 to 76.9.127.25476.9.127.2554,094
15376.9.128.0/2076.9.128.1 to 76.9.143.25476.9.143.2554,094
15476.9.144.0/2076.9.144.1 to 76.9.159.25476.9.159.2554,094
15576.9.160.0/2076.9.160.1 to 76.9.175.25476.9.175.2554,094
15676.9.176.0/2076.9.176.1 to 76.9.191.25476.9.191.2554,094
15776.9.192.0/2076.9.192.1 to 76.9.207.25476.9.207.2554,094
15876.9.208.0/2076.9.208.1 to 76.9.223.25476.9.223.2554,094
15976.9.224.0/2076.9.224.1 to 76.9.239.25476.9.239.2554,094
16076.9.240.0/2076.9.240.1 to 76.9.255.25476.9.255.2554,094
16176.10.0.0/2076.10.0.1 to 76.10.15.25476.10.15.2554,094
16276.10.16.0/2076.10.16.1 to 76.10.31.25476.10.31.2554,094
16376.10.32.0/2076.10.32.1 to 76.10.47.25476.10.47.2554,094
16476.10.48.0/2076.10.48.1 to 76.10.63.25476.10.63.2554,094
16576.10.64.0/2076.10.64.1 to 76.10.79.25476.10.79.2554,094
16676.10.80.0/2076.10.80.1 to 76.10.95.25476.10.95.2554,094
16776.10.96.0/2076.10.96.1 to 76.10.111.25476.10.111.2554,094
16876.10.112.0/2076.10.112.1 to 76.10.127.25476.10.127.2554,094
16976.10.128.0/2076.10.128.1 to 76.10.143.25476.10.143.2554,094
17076.10.144.0/2076.10.144.1 to 76.10.159.25476.10.159.2554,094
17176.10.160.0/2076.10.160.1 to 76.10.175.25476.10.175.2554,094
17276.10.176.0/2076.10.176.1 to 76.10.191.25476.10.191.2554,094
17376.10.192.0/2076.10.192.1 to 76.10.207.25476.10.207.2554,094
17476.10.208.0/2076.10.208.1 to 76.10.223.25476.10.223.2554,094
17576.10.224.0/2076.10.224.1 to 76.10.239.25476.10.239.2554,094
17676.10.240.0/2076.10.240.1 to 76.10.255.25476.10.255.2554,094
17776.11.0.0/2076.11.0.1 to 76.11.15.25476.11.15.2554,094
17876.11.16.0/2076.11.16.1 to 76.11.31.25476.11.31.2554,094
17976.11.32.0/2076.11.32.1 to 76.11.47.25476.11.47.2554,094
18076.11.48.0/2076.11.48.1 to 76.11.63.25476.11.63.2554,094
18176.11.64.0/2076.11.64.1 to 76.11.79.25476.11.79.2554,094
18276.11.80.0/2076.11.80.1 to 76.11.95.25476.11.95.2554,094
18376.11.96.0/2076.11.96.1 to 76.11.111.25476.11.111.2554,094
18476.11.112.0/2076.11.112.1 to 76.11.127.25476.11.127.2554,094
18576.11.128.0/2076.11.128.1 to 76.11.143.25476.11.143.2554,094
18676.11.144.0/2076.11.144.1 to 76.11.159.25476.11.159.2554,094
18776.11.160.0/2076.11.160.1 to 76.11.175.25476.11.175.2554,094
18876.11.176.0/2076.11.176.1 to 76.11.191.25476.11.191.2554,094
18976.11.192.0/2076.11.192.1 to 76.11.207.25476.11.207.2554,094
19076.11.208.0/2076.11.208.1 to 76.11.223.25476.11.223.2554,094
19176.11.224.0/2076.11.224.1 to 76.11.239.25476.11.239.2554,094
19276.11.240.0/2076.11.240.1 to 76.11.255.25476.11.255.2554,094
19376.12.0.0/2076.12.0.1 to 76.12.15.25476.12.15.2554,094
19476.12.16.0/2076.12.16.1 to 76.12.31.25476.12.31.2554,094
19576.12.32.0/2076.12.32.1 to 76.12.47.25476.12.47.2554,094
19676.12.48.0/2076.12.48.1 to 76.12.63.25476.12.63.2554,094
19776.12.64.0/2076.12.64.1 to 76.12.79.25476.12.79.2554,094
19876.12.80.0/2076.12.80.1 to 76.12.95.25476.12.95.2554,094
19976.12.96.0/2076.12.96.1 to 76.12.111.25476.12.111.2554,094
20076.12.112.0/2076.12.112.1 to 76.12.127.25476.12.127.2554,094
20176.12.128.0/2076.12.128.1 to 76.12.143.25476.12.143.2554,094
20276.12.144.0/2076.12.144.1 to 76.12.159.25476.12.159.2554,094
20376.12.160.0/2076.12.160.1 to 76.12.175.25476.12.175.2554,094
20476.12.176.0/2076.12.176.1 to 76.12.191.25476.12.191.2554,094
20576.12.192.0/2076.12.192.1 to 76.12.207.25476.12.207.2554,094
20676.12.208.0/2076.12.208.1 to 76.12.223.25476.12.223.2554,094
20776.12.224.0/2076.12.224.1 to 76.12.239.25476.12.239.2554,094
20876.12.240.0/2076.12.240.1 to 76.12.255.25476.12.255.2554,094
20976.13.0.0/2076.13.0.1 to 76.13.15.25476.13.15.2554,094
21076.13.16.0/2076.13.16.1 to 76.13.31.25476.13.31.2554,094
21176.13.32.0/2076.13.32.1 to 76.13.47.25476.13.47.2554,094
21276.13.48.0/2076.13.48.1 to 76.13.63.25476.13.63.2554,094
21376.13.64.0/2076.13.64.1 to 76.13.79.25476.13.79.2554,094
21476.13.80.0/2076.13.80.1 to 76.13.95.25476.13.95.2554,094
21576.13.96.0/2076.13.96.1 to 76.13.111.25476.13.111.2554,094
21676.13.112.0/2076.13.112.1 to 76.13.127.25476.13.127.2554,094
21776.13.128.0/2076.13.128.1 to 76.13.143.25476.13.143.2554,094
21876.13.144.0/2076.13.144.1 to 76.13.159.25476.13.159.2554,094
21976.13.160.0/2076.13.160.1 to 76.13.175.25476.13.175.2554,094
22076.13.176.0/2076.13.176.1 to 76.13.191.25476.13.191.2554,094
22176.13.192.0/2076.13.192.1 to 76.13.207.25476.13.207.2554,094
22276.13.208.0/2076.13.208.1 to 76.13.223.25476.13.223.2554,094
22376.13.224.0/2076.13.224.1 to 76.13.239.25476.13.239.2554,094
22476.13.240.0/2076.13.240.1 to 76.13.255.25476.13.255.2554,094
22576.14.0.0/2076.14.0.1 to 76.14.15.25476.14.15.2554,094
22676.14.16.0/2076.14.16.1 to 76.14.31.25476.14.31.2554,094
22776.14.32.0/2076.14.32.1 to 76.14.47.25476.14.47.2554,094
22876.14.48.0/2076.14.48.1 to 76.14.63.25476.14.63.2554,094
22976.14.64.0/2076.14.64.1 to 76.14.79.25476.14.79.2554,094
23076.14.80.0/2076.14.80.1 to 76.14.95.25476.14.95.2554,094
23176.14.96.0/2076.14.96.1 to 76.14.111.25476.14.111.2554,094
23276.14.112.0/2076.14.112.1 to 76.14.127.25476.14.127.2554,094
23376.14.128.0/2076.14.128.1 to 76.14.143.25476.14.143.2554,094
23476.14.144.0/2076.14.144.1 to 76.14.159.25476.14.159.2554,094
23576.14.160.0/2076.14.160.1 to 76.14.175.25476.14.175.2554,094
23676.14.176.0/2076.14.176.1 to 76.14.191.25476.14.191.2554,094
23776.14.192.0/2076.14.192.1 to 76.14.207.25476.14.207.2554,094
23876.14.208.0/2076.14.208.1 to 76.14.223.25476.14.223.2554,094
23976.14.224.0/2076.14.224.1 to 76.14.239.25476.14.239.2554,094
24076.14.240.0/2076.14.240.1 to 76.14.255.25476.14.255.2554,094
24176.15.0.0/2076.15.0.1 to 76.15.15.25476.15.15.2554,094
24276.15.16.0/2076.15.16.1 to 76.15.31.25476.15.31.2554,094
24376.15.32.0/2076.15.32.1 to 76.15.47.25476.15.47.2554,094
24476.15.48.0/2076.15.48.1 to 76.15.63.25476.15.63.2554,094
24576.15.64.0/2076.15.64.1 to 76.15.79.25476.15.79.2554,094
24676.15.80.0/2076.15.80.1 to 76.15.95.25476.15.95.2554,094
24776.15.96.0/2076.15.96.1 to 76.15.111.25476.15.111.2554,094
24876.15.112.0/2076.15.112.1 to 76.15.127.25476.15.127.2554,094
24976.15.128.0/2076.15.128.1 to 76.15.143.25476.15.143.2554,094
25076.15.144.0/2076.15.144.1 to 76.15.159.25476.15.159.2554,094
25176.15.160.0/2076.15.160.1 to 76.15.175.25476.15.175.2554,094
25276.15.176.0/2076.15.176.1 to 76.15.191.25476.15.191.2554,094
25376.15.192.0/2076.15.192.1 to 76.15.207.25476.15.207.2554,094
25476.15.208.0/2076.15.208.1 to 76.15.223.25476.15.223.2554,094
25576.15.224.0/2076.15.224.1 to 76.15.239.25476.15.239.2554,094
25676.15.240.0/2076.15.240.1 to 76.15.255.25476.15.255.2554,094

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.