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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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.

Prefix/12
Addresses2^116
/64 networks2^52
Network
26e0::/12
First address
26e0::
Last address
26ef:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
26e0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.6.2.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

26e0::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
126e0::/2426e0:ff:ffff:ffff:ffff:ffff:ffff:ffff
226e0:100::/2426e0:1ff:ffff:ffff:ffff:ffff:ffff:ffff
326e0:200::/2426e0:2ff:ffff:ffff:ffff:ffff:ffff:ffff
426e0:300::/2426e0:3ff:ffff:ffff:ffff:ffff:ffff:ffff
526e0:400::/2426e0:4ff:ffff:ffff:ffff:ffff:ffff:ffff
626e0:500::/2426e0:5ff:ffff:ffff:ffff:ffff:ffff:ffff
726e0:600::/2426e0:6ff:ffff:ffff:ffff:ffff:ffff:ffff
826e0:700::/2426e0:7ff:ffff:ffff:ffff:ffff:ffff:ffff
926e0:800::/2426e0:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1026e0:900::/2426e0:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1126e0:a00::/2426e0:aff:ffff:ffff:ffff:ffff:ffff:ffff
1226e0:b00::/2426e0:bff:ffff:ffff:ffff:ffff:ffff:ffff
1326e0:c00::/2426e0:cff:ffff:ffff:ffff:ffff:ffff:ffff
1426e0:d00::/2426e0:dff:ffff:ffff:ffff:ffff:ffff:ffff
1526e0:e00::/2426e0:eff:ffff:ffff:ffff:ffff:ffff:ffff
1626e0:f00::/2426e0:fff:ffff:ffff:ffff:ffff:ffff:ffff
1726e0:1000::/2426e0:10ff:ffff:ffff:ffff:ffff:ffff:ffff
1826e0:1100::/2426e0:11ff:ffff:ffff:ffff:ffff:ffff:ffff
1926e0:1200::/2426e0:12ff:ffff:ffff:ffff:ffff:ffff:ffff
2026e0:1300::/2426e0:13ff:ffff:ffff:ffff:ffff:ffff:ffff
2126e0:1400::/2426e0:14ff:ffff:ffff:ffff:ffff:ffff:ffff
2226e0:1500::/2426e0:15ff:ffff:ffff:ffff:ffff:ffff:ffff
2326e0:1600::/2426e0:16ff:ffff:ffff:ffff:ffff:ffff:ffff
2426e0:1700::/2426e0:17ff:ffff:ffff:ffff:ffff:ffff:ffff
2526e0:1800::/2426e0:18ff:ffff:ffff:ffff:ffff:ffff:ffff
2626e0:1900::/2426e0:19ff:ffff:ffff:ffff:ffff:ffff:ffff
2726e0:1a00::/2426e0:1aff:ffff:ffff:ffff:ffff:ffff:ffff
2826e0:1b00::/2426e0:1bff:ffff:ffff:ffff:ffff:ffff:ffff
2926e0:1c00::/2426e0:1cff:ffff:ffff:ffff:ffff:ffff:ffff
3026e0:1d00::/2426e0:1dff:ffff:ffff:ffff:ffff:ffff:ffff
3126e0:1e00::/2426e0:1eff:ffff:ffff:ffff:ffff:ffff:ffff
3226e0:1f00::/2426e0:1fff:ffff:ffff:ffff:ffff:ffff:ffff
3326e0:2000::/2426e0:20ff:ffff:ffff:ffff:ffff:ffff:ffff
3426e0:2100::/2426e0:21ff:ffff:ffff:ffff:ffff:ffff:ffff
3526e0:2200::/2426e0:22ff:ffff:ffff:ffff:ffff:ffff:ffff
3626e0:2300::/2426e0:23ff:ffff:ffff:ffff:ffff:ffff:ffff
3726e0:2400::/2426e0:24ff:ffff:ffff:ffff:ffff:ffff:ffff
3826e0:2500::/2426e0:25ff:ffff:ffff:ffff:ffff:ffff:ffff
3926e0:2600::/2426e0:26ff:ffff:ffff:ffff:ffff:ffff:ffff
4026e0:2700::/2426e0:27ff:ffff:ffff:ffff:ffff:ffff:ffff
4126e0:2800::/2426e0:28ff:ffff:ffff:ffff:ffff:ffff:ffff
4226e0:2900::/2426e0:29ff:ffff:ffff:ffff:ffff:ffff:ffff
4326e0:2a00::/2426e0:2aff:ffff:ffff:ffff:ffff:ffff:ffff
4426e0:2b00::/2426e0:2bff:ffff:ffff:ffff:ffff:ffff:ffff
4526e0:2c00::/2426e0:2cff:ffff:ffff:ffff:ffff:ffff:ffff
4626e0:2d00::/2426e0:2dff:ffff:ffff:ffff:ffff:ffff:ffff
4726e0:2e00::/2426e0:2eff:ffff:ffff:ffff:ffff:ffff:ffff
4826e0:2f00::/2426e0:2fff:ffff:ffff:ffff:ffff:ffff:ffff
4926e0:3000::/2426e0:30ff:ffff:ffff:ffff:ffff:ffff:ffff
5026e0:3100::/2426e0:31ff:ffff:ffff:ffff:ffff:ffff:ffff
5126e0:3200::/2426e0:32ff:ffff:ffff:ffff:ffff:ffff:ffff
5226e0:3300::/2426e0:33ff:ffff:ffff:ffff:ffff:ffff:ffff
5326e0:3400::/2426e0:34ff:ffff:ffff:ffff:ffff:ffff:ffff
5426e0:3500::/2426e0:35ff:ffff:ffff:ffff:ffff:ffff:ffff
5526e0:3600::/2426e0:36ff:ffff:ffff:ffff:ffff:ffff:ffff
5626e0:3700::/2426e0:37ff:ffff:ffff:ffff:ffff:ffff:ffff
5726e0:3800::/2426e0:38ff:ffff:ffff:ffff:ffff:ffff:ffff
5826e0:3900::/2426e0:39ff:ffff:ffff:ffff:ffff:ffff:ffff
5926e0:3a00::/2426e0:3aff:ffff:ffff:ffff:ffff:ffff:ffff
6026e0:3b00::/2426e0:3bff:ffff:ffff:ffff:ffff:ffff:ffff
6126e0:3c00::/2426e0:3cff:ffff:ffff:ffff:ffff:ffff:ffff
6226e0:3d00::/2426e0:3dff:ffff:ffff:ffff:ffff:ffff:ffff
6326e0:3e00::/2426e0:3eff:ffff:ffff:ffff:ffff:ffff:ffff
6426e0:3f00::/2426e0:3fff:ffff:ffff:ffff:ffff:ffff:ffff
6526e0:4000::/2426e0:40ff:ffff:ffff:ffff:ffff:ffff:ffff
6626e0:4100::/2426e0:41ff:ffff:ffff:ffff:ffff:ffff:ffff
6726e0:4200::/2426e0:42ff:ffff:ffff:ffff:ffff:ffff:ffff
6826e0:4300::/2426e0:43ff:ffff:ffff:ffff:ffff:ffff:ffff
6926e0:4400::/2426e0:44ff:ffff:ffff:ffff:ffff:ffff:ffff
7026e0:4500::/2426e0:45ff:ffff:ffff:ffff:ffff:ffff:ffff
7126e0:4600::/2426e0:46ff:ffff:ffff:ffff:ffff:ffff:ffff
7226e0:4700::/2426e0:47ff:ffff:ffff:ffff:ffff:ffff:ffff
7326e0:4800::/2426e0:48ff:ffff:ffff:ffff:ffff:ffff:ffff
7426e0:4900::/2426e0:49ff:ffff:ffff:ffff:ffff:ffff:ffff
7526e0:4a00::/2426e0:4aff:ffff:ffff:ffff:ffff:ffff:ffff
7626e0:4b00::/2426e0:4bff:ffff:ffff:ffff:ffff:ffff:ffff
7726e0:4c00::/2426e0:4cff:ffff:ffff:ffff:ffff:ffff:ffff
7826e0:4d00::/2426e0:4dff:ffff:ffff:ffff:ffff:ffff:ffff
7926e0:4e00::/2426e0:4eff:ffff:ffff:ffff:ffff:ffff:ffff
8026e0:4f00::/2426e0:4fff:ffff:ffff:ffff:ffff:ffff:ffff
8126e0:5000::/2426e0:50ff:ffff:ffff:ffff:ffff:ffff:ffff
8226e0:5100::/2426e0:51ff:ffff:ffff:ffff:ffff:ffff:ffff
8326e0:5200::/2426e0:52ff:ffff:ffff:ffff:ffff:ffff:ffff
8426e0:5300::/2426e0:53ff:ffff:ffff:ffff:ffff:ffff:ffff
8526e0:5400::/2426e0:54ff:ffff:ffff:ffff:ffff:ffff:ffff
8626e0:5500::/2426e0:55ff:ffff:ffff:ffff:ffff:ffff:ffff
8726e0:5600::/2426e0:56ff:ffff:ffff:ffff:ffff:ffff:ffff
8826e0:5700::/2426e0:57ff:ffff:ffff:ffff:ffff:ffff:ffff
8926e0:5800::/2426e0:58ff:ffff:ffff:ffff:ffff:ffff:ffff
9026e0:5900::/2426e0:59ff:ffff:ffff:ffff:ffff:ffff:ffff
9126e0:5a00::/2426e0:5aff:ffff:ffff:ffff:ffff:ffff:ffff
9226e0:5b00::/2426e0:5bff:ffff:ffff:ffff:ffff:ffff:ffff
9326e0:5c00::/2426e0:5cff:ffff:ffff:ffff:ffff:ffff:ffff
9426e0:5d00::/2426e0:5dff:ffff:ffff:ffff:ffff:ffff:ffff
9526e0:5e00::/2426e0:5eff:ffff:ffff:ffff:ffff:ffff:ffff
9626e0:5f00::/2426e0:5fff:ffff:ffff:ffff:ffff:ffff:ffff
9726e0:6000::/2426e0:60ff:ffff:ffff:ffff:ffff:ffff:ffff
9826e0:6100::/2426e0:61ff:ffff:ffff:ffff:ffff:ffff:ffff
9926e0:6200::/2426e0:62ff:ffff:ffff:ffff:ffff:ffff:ffff
10026e0:6300::/2426e0:63ff:ffff:ffff:ffff:ffff:ffff:ffff
10126e0:6400::/2426e0:64ff:ffff:ffff:ffff:ffff:ffff:ffff
10226e0:6500::/2426e0:65ff:ffff:ffff:ffff:ffff:ffff:ffff
10326e0:6600::/2426e0:66ff:ffff:ffff:ffff:ffff:ffff:ffff
10426e0:6700::/2426e0:67ff:ffff:ffff:ffff:ffff:ffff:ffff
10526e0:6800::/2426e0:68ff:ffff:ffff:ffff:ffff:ffff:ffff
10626e0:6900::/2426e0:69ff:ffff:ffff:ffff:ffff:ffff:ffff
10726e0:6a00::/2426e0:6aff:ffff:ffff:ffff:ffff:ffff:ffff
10826e0:6b00::/2426e0:6bff:ffff:ffff:ffff:ffff:ffff:ffff
10926e0:6c00::/2426e0:6cff:ffff:ffff:ffff:ffff:ffff:ffff
11026e0:6d00::/2426e0:6dff:ffff:ffff:ffff:ffff:ffff:ffff
11126e0:6e00::/2426e0:6eff:ffff:ffff:ffff:ffff:ffff:ffff
11226e0:6f00::/2426e0:6fff:ffff:ffff:ffff:ffff:ffff:ffff
11326e0:7000::/2426e0:70ff:ffff:ffff:ffff:ffff:ffff:ffff
11426e0:7100::/2426e0:71ff:ffff:ffff:ffff:ffff:ffff:ffff
11526e0:7200::/2426e0:72ff:ffff:ffff:ffff:ffff:ffff:ffff
11626e0:7300::/2426e0:73ff:ffff:ffff:ffff:ffff:ffff:ffff
11726e0:7400::/2426e0:74ff:ffff:ffff:ffff:ffff:ffff:ffff
11826e0:7500::/2426e0:75ff:ffff:ffff:ffff:ffff:ffff:ffff
11926e0:7600::/2426e0:76ff:ffff:ffff:ffff:ffff:ffff:ffff
12026e0:7700::/2426e0:77ff:ffff:ffff:ffff:ffff:ffff:ffff
12126e0:7800::/2426e0:78ff:ffff:ffff:ffff:ffff:ffff:ffff
12226e0:7900::/2426e0:79ff:ffff:ffff:ffff:ffff:ffff:ffff
12326e0:7a00::/2426e0:7aff:ffff:ffff:ffff:ffff:ffff:ffff
12426e0:7b00::/2426e0:7bff:ffff:ffff:ffff:ffff:ffff:ffff
12526e0:7c00::/2426e0:7cff:ffff:ffff:ffff:ffff:ffff:ffff
12626e0:7d00::/2426e0:7dff:ffff:ffff:ffff:ffff:ffff:ffff
12726e0:7e00::/2426e0:7eff:ffff:ffff:ffff:ffff:ffff:ffff
12826e0:7f00::/2426e0:7fff:ffff:ffff:ffff:ffff:ffff:ffff
12926e0:8000::/2426e0:80ff:ffff:ffff:ffff:ffff:ffff:ffff
13026e0:8100::/2426e0:81ff:ffff:ffff:ffff:ffff:ffff:ffff
13126e0:8200::/2426e0:82ff:ffff:ffff:ffff:ffff:ffff:ffff
13226e0:8300::/2426e0:83ff:ffff:ffff:ffff:ffff:ffff:ffff
13326e0:8400::/2426e0:84ff:ffff:ffff:ffff:ffff:ffff:ffff
13426e0:8500::/2426e0:85ff:ffff:ffff:ffff:ffff:ffff:ffff
13526e0:8600::/2426e0:86ff:ffff:ffff:ffff:ffff:ffff:ffff
13626e0:8700::/2426e0:87ff:ffff:ffff:ffff:ffff:ffff:ffff
13726e0:8800::/2426e0:88ff:ffff:ffff:ffff:ffff:ffff:ffff
13826e0:8900::/2426e0:89ff:ffff:ffff:ffff:ffff:ffff:ffff
13926e0:8a00::/2426e0:8aff:ffff:ffff:ffff:ffff:ffff:ffff
14026e0:8b00::/2426e0:8bff:ffff:ffff:ffff:ffff:ffff:ffff
14126e0:8c00::/2426e0:8cff:ffff:ffff:ffff:ffff:ffff:ffff
14226e0:8d00::/2426e0:8dff:ffff:ffff:ffff:ffff:ffff:ffff
14326e0:8e00::/2426e0:8eff:ffff:ffff:ffff:ffff:ffff:ffff
14426e0:8f00::/2426e0:8fff:ffff:ffff:ffff:ffff:ffff:ffff
14526e0:9000::/2426e0:90ff:ffff:ffff:ffff:ffff:ffff:ffff
14626e0:9100::/2426e0:91ff:ffff:ffff:ffff:ffff:ffff:ffff
14726e0:9200::/2426e0:92ff:ffff:ffff:ffff:ffff:ffff:ffff
14826e0:9300::/2426e0:93ff:ffff:ffff:ffff:ffff:ffff:ffff
14926e0:9400::/2426e0:94ff:ffff:ffff:ffff:ffff:ffff:ffff
15026e0:9500::/2426e0:95ff:ffff:ffff:ffff:ffff:ffff:ffff
15126e0:9600::/2426e0:96ff:ffff:ffff:ffff:ffff:ffff:ffff
15226e0:9700::/2426e0:97ff:ffff:ffff:ffff:ffff:ffff:ffff
15326e0:9800::/2426e0:98ff:ffff:ffff:ffff:ffff:ffff:ffff
15426e0:9900::/2426e0:99ff:ffff:ffff:ffff:ffff:ffff:ffff
15526e0:9a00::/2426e0:9aff:ffff:ffff:ffff:ffff:ffff:ffff
15626e0:9b00::/2426e0:9bff:ffff:ffff:ffff:ffff:ffff:ffff
15726e0:9c00::/2426e0:9cff:ffff:ffff:ffff:ffff:ffff:ffff
15826e0:9d00::/2426e0:9dff:ffff:ffff:ffff:ffff:ffff:ffff
15926e0:9e00::/2426e0:9eff:ffff:ffff:ffff:ffff:ffff:ffff
16026e0:9f00::/2426e0:9fff:ffff:ffff:ffff:ffff:ffff:ffff
16126e0:a000::/2426e0:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
16226e0:a100::/2426e0:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
16326e0:a200::/2426e0:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
16426e0:a300::/2426e0:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
16526e0:a400::/2426e0:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
16626e0:a500::/2426e0:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
16726e0:a600::/2426e0:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
16826e0:a700::/2426e0:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
16926e0:a800::/2426e0:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
17026e0:a900::/2426e0:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
17126e0:aa00::/2426e0:aaff:ffff:ffff:ffff:ffff:ffff:ffff
17226e0:ab00::/2426e0:abff:ffff:ffff:ffff:ffff:ffff:ffff
17326e0:ac00::/2426e0:acff:ffff:ffff:ffff:ffff:ffff:ffff
17426e0:ad00::/2426e0:adff:ffff:ffff:ffff:ffff:ffff:ffff
17526e0:ae00::/2426e0:aeff:ffff:ffff:ffff:ffff:ffff:ffff
17626e0:af00::/2426e0:afff:ffff:ffff:ffff:ffff:ffff:ffff
17726e0:b000::/2426e0:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
17826e0:b100::/2426e0:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
17926e0:b200::/2426e0:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
18026e0:b300::/2426e0:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
18126e0:b400::/2426e0:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
18226e0:b500::/2426e0:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
18326e0:b600::/2426e0:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
18426e0:b700::/2426e0:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
18526e0:b800::/2426e0:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
18626e0:b900::/2426e0:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
18726e0:ba00::/2426e0:baff:ffff:ffff:ffff:ffff:ffff:ffff
18826e0:bb00::/2426e0:bbff:ffff:ffff:ffff:ffff:ffff:ffff
18926e0:bc00::/2426e0:bcff:ffff:ffff:ffff:ffff:ffff:ffff
19026e0:bd00::/2426e0:bdff:ffff:ffff:ffff:ffff:ffff:ffff
19126e0:be00::/2426e0:beff:ffff:ffff:ffff:ffff:ffff:ffff
19226e0:bf00::/2426e0:bfff:ffff:ffff:ffff:ffff:ffff:ffff
19326e0:c000::/2426e0:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
19426e0:c100::/2426e0:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
19526e0:c200::/2426e0:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
19626e0:c300::/2426e0:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
19726e0:c400::/2426e0:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
19826e0:c500::/2426e0:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
19926e0:c600::/2426e0:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
20026e0:c700::/2426e0:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
20126e0:c800::/2426e0:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
20226e0:c900::/2426e0:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
20326e0:ca00::/2426e0:caff:ffff:ffff:ffff:ffff:ffff:ffff
20426e0:cb00::/2426e0:cbff:ffff:ffff:ffff:ffff:ffff:ffff
20526e0:cc00::/2426e0:ccff:ffff:ffff:ffff:ffff:ffff:ffff
20626e0:cd00::/2426e0:cdff:ffff:ffff:ffff:ffff:ffff:ffff
20726e0:ce00::/2426e0:ceff:ffff:ffff:ffff:ffff:ffff:ffff
20826e0:cf00::/2426e0:cfff:ffff:ffff:ffff:ffff:ffff:ffff
20926e0:d000::/2426e0:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
21026e0:d100::/2426e0:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
21126e0:d200::/2426e0:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
21226e0:d300::/2426e0:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
21326e0:d400::/2426e0:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
21426e0:d500::/2426e0:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
21526e0:d600::/2426e0:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
21626e0:d700::/2426e0:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
21726e0:d800::/2426e0:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
21826e0:d900::/2426e0:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
21926e0:da00::/2426e0:daff:ffff:ffff:ffff:ffff:ffff:ffff
22026e0:db00::/2426e0:dbff:ffff:ffff:ffff:ffff:ffff:ffff
22126e0:dc00::/2426e0:dcff:ffff:ffff:ffff:ffff:ffff:ffff
22226e0:dd00::/2426e0:ddff:ffff:ffff:ffff:ffff:ffff:ffff
22326e0:de00::/2426e0:deff:ffff:ffff:ffff:ffff:ffff:ffff
22426e0:df00::/2426e0:dfff:ffff:ffff:ffff:ffff:ffff:ffff
22526e0:e000::/2426e0:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
22626e0:e100::/2426e0:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
22726e0:e200::/2426e0:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
22826e0:e300::/2426e0:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
22926e0:e400::/2426e0:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
23026e0:e500::/2426e0:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
23126e0:e600::/2426e0:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
23226e0:e700::/2426e0:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
23326e0:e800::/2426e0:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
23426e0:e900::/2426e0:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
23526e0:ea00::/2426e0:eaff:ffff:ffff:ffff:ffff:ffff:ffff
23626e0:eb00::/2426e0:ebff:ffff:ffff:ffff:ffff:ffff:ffff
23726e0:ec00::/2426e0:ecff:ffff:ffff:ffff:ffff:ffff:ffff
23826e0:ed00::/2426e0:edff:ffff:ffff:ffff:ffff:ffff:ffff
23926e0:ee00::/2426e0:eeff:ffff:ffff:ffff:ffff:ffff:ffff
24026e0:ef00::/2426e0:efff:ffff:ffff:ffff:ffff:ffff:ffff
24126e0:f000::/2426e0:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
24226e0:f100::/2426e0:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
24326e0:f200::/2426e0:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
24426e0:f300::/2426e0:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
24526e0:f400::/2426e0:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
24626e0:f500::/2426e0:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
24726e0:f600::/2426e0:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
24826e0:f700::/2426e0:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
24926e0:f800::/2426e0:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
25026e0:f900::/2426e0:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
25126e0:fa00::/2426e0:faff:ffff:ffff:ffff:ffff:ffff:ffff
25226e0:fb00::/2426e0:fbff:ffff:ffff:ffff:ffff:ffff:ffff
25326e0:fc00::/2426e0:fcff:ffff:ffff:ffff:ffff:ffff:ffff
25426e0:fd00::/2426e0:fdff:ffff:ffff:ffff:ffff:ffff:ffff
25526e0:fe00::/2426e0:feff:ffff:ffff:ffff:ffff:ffff:ffff
25626e0:ff00::/2426e0:ffff:ffff:ffff:ffff:ffff:ffff:ffff

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.