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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
28e0::/12
First address
28e0::
Last address
28ef: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
28e0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.8.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

28e0::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
128e0::/2828e0:f:ffff:ffff:ffff:ffff:ffff:ffff
228e0:10::/2828e0:1f:ffff:ffff:ffff:ffff:ffff:ffff
328e0:20::/2828e0:2f:ffff:ffff:ffff:ffff:ffff:ffff
428e0:30::/2828e0:3f:ffff:ffff:ffff:ffff:ffff:ffff
528e0:40::/2828e0:4f:ffff:ffff:ffff:ffff:ffff:ffff
628e0:50::/2828e0:5f:ffff:ffff:ffff:ffff:ffff:ffff
728e0:60::/2828e0:6f:ffff:ffff:ffff:ffff:ffff:ffff
828e0:70::/2828e0:7f:ffff:ffff:ffff:ffff:ffff:ffff
928e0:80::/2828e0:8f:ffff:ffff:ffff:ffff:ffff:ffff
1028e0:90::/2828e0:9f:ffff:ffff:ffff:ffff:ffff:ffff
1128e0:a0::/2828e0:af:ffff:ffff:ffff:ffff:ffff:ffff
1228e0:b0::/2828e0:bf:ffff:ffff:ffff:ffff:ffff:ffff
1328e0:c0::/2828e0:cf:ffff:ffff:ffff:ffff:ffff:ffff
1428e0:d0::/2828e0:df:ffff:ffff:ffff:ffff:ffff:ffff
1528e0:e0::/2828e0:ef:ffff:ffff:ffff:ffff:ffff:ffff
1628e0:f0::/2828e0:ff:ffff:ffff:ffff:ffff:ffff:ffff
1728e0:100::/2828e0:10f:ffff:ffff:ffff:ffff:ffff:ffff
1828e0:110::/2828e0:11f:ffff:ffff:ffff:ffff:ffff:ffff
1928e0:120::/2828e0:12f:ffff:ffff:ffff:ffff:ffff:ffff
2028e0:130::/2828e0:13f:ffff:ffff:ffff:ffff:ffff:ffff
2128e0:140::/2828e0:14f:ffff:ffff:ffff:ffff:ffff:ffff
2228e0:150::/2828e0:15f:ffff:ffff:ffff:ffff:ffff:ffff
2328e0:160::/2828e0:16f:ffff:ffff:ffff:ffff:ffff:ffff
2428e0:170::/2828e0:17f:ffff:ffff:ffff:ffff:ffff:ffff
2528e0:180::/2828e0:18f:ffff:ffff:ffff:ffff:ffff:ffff
2628e0:190::/2828e0:19f:ffff:ffff:ffff:ffff:ffff:ffff
2728e0:1a0::/2828e0:1af:ffff:ffff:ffff:ffff:ffff:ffff
2828e0:1b0::/2828e0:1bf:ffff:ffff:ffff:ffff:ffff:ffff
2928e0:1c0::/2828e0:1cf:ffff:ffff:ffff:ffff:ffff:ffff
3028e0:1d0::/2828e0:1df:ffff:ffff:ffff:ffff:ffff:ffff
3128e0:1e0::/2828e0:1ef:ffff:ffff:ffff:ffff:ffff:ffff
3228e0:1f0::/2828e0:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3328e0:200::/2828e0:20f:ffff:ffff:ffff:ffff:ffff:ffff
3428e0:210::/2828e0:21f:ffff:ffff:ffff:ffff:ffff:ffff
3528e0:220::/2828e0:22f:ffff:ffff:ffff:ffff:ffff:ffff
3628e0:230::/2828e0:23f:ffff:ffff:ffff:ffff:ffff:ffff
3728e0:240::/2828e0:24f:ffff:ffff:ffff:ffff:ffff:ffff
3828e0:250::/2828e0:25f:ffff:ffff:ffff:ffff:ffff:ffff
3928e0:260::/2828e0:26f:ffff:ffff:ffff:ffff:ffff:ffff
4028e0:270::/2828e0:27f:ffff:ffff:ffff:ffff:ffff:ffff
4128e0:280::/2828e0:28f:ffff:ffff:ffff:ffff:ffff:ffff
4228e0:290::/2828e0:29f:ffff:ffff:ffff:ffff:ffff:ffff
4328e0:2a0::/2828e0:2af:ffff:ffff:ffff:ffff:ffff:ffff
4428e0:2b0::/2828e0:2bf:ffff:ffff:ffff:ffff:ffff:ffff
4528e0:2c0::/2828e0:2cf:ffff:ffff:ffff:ffff:ffff:ffff
4628e0:2d0::/2828e0:2df:ffff:ffff:ffff:ffff:ffff:ffff
4728e0:2e0::/2828e0:2ef:ffff:ffff:ffff:ffff:ffff:ffff
4828e0:2f0::/2828e0:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4928e0:300::/2828e0:30f:ffff:ffff:ffff:ffff:ffff:ffff
5028e0:310::/2828e0:31f:ffff:ffff:ffff:ffff:ffff:ffff
5128e0:320::/2828e0:32f:ffff:ffff:ffff:ffff:ffff:ffff
5228e0:330::/2828e0:33f:ffff:ffff:ffff:ffff:ffff:ffff
5328e0:340::/2828e0:34f:ffff:ffff:ffff:ffff:ffff:ffff
5428e0:350::/2828e0:35f:ffff:ffff:ffff:ffff:ffff:ffff
5528e0:360::/2828e0:36f:ffff:ffff:ffff:ffff:ffff:ffff
5628e0:370::/2828e0:37f:ffff:ffff:ffff:ffff:ffff:ffff
5728e0:380::/2828e0:38f:ffff:ffff:ffff:ffff:ffff:ffff
5828e0:390::/2828e0:39f:ffff:ffff:ffff:ffff:ffff:ffff
5928e0:3a0::/2828e0:3af:ffff:ffff:ffff:ffff:ffff:ffff
6028e0:3b0::/2828e0:3bf:ffff:ffff:ffff:ffff:ffff:ffff
6128e0:3c0::/2828e0:3cf:ffff:ffff:ffff:ffff:ffff:ffff
6228e0:3d0::/2828e0:3df:ffff:ffff:ffff:ffff:ffff:ffff
6328e0:3e0::/2828e0:3ef:ffff:ffff:ffff:ffff:ffff:ffff
6428e0:3f0::/2828e0:3ff:ffff:ffff:ffff:ffff:ffff:ffff
6528e0:400::/2828e0:40f:ffff:ffff:ffff:ffff:ffff:ffff
6628e0:410::/2828e0:41f:ffff:ffff:ffff:ffff:ffff:ffff
6728e0:420::/2828e0:42f:ffff:ffff:ffff:ffff:ffff:ffff
6828e0:430::/2828e0:43f:ffff:ffff:ffff:ffff:ffff:ffff
6928e0:440::/2828e0:44f:ffff:ffff:ffff:ffff:ffff:ffff
7028e0:450::/2828e0:45f:ffff:ffff:ffff:ffff:ffff:ffff
7128e0:460::/2828e0:46f:ffff:ffff:ffff:ffff:ffff:ffff
7228e0:470::/2828e0:47f:ffff:ffff:ffff:ffff:ffff:ffff
7328e0:480::/2828e0:48f:ffff:ffff:ffff:ffff:ffff:ffff
7428e0:490::/2828e0:49f:ffff:ffff:ffff:ffff:ffff:ffff
7528e0:4a0::/2828e0:4af:ffff:ffff:ffff:ffff:ffff:ffff
7628e0:4b0::/2828e0:4bf:ffff:ffff:ffff:ffff:ffff:ffff
7728e0:4c0::/2828e0:4cf:ffff:ffff:ffff:ffff:ffff:ffff
7828e0:4d0::/2828e0:4df:ffff:ffff:ffff:ffff:ffff:ffff
7928e0:4e0::/2828e0:4ef:ffff:ffff:ffff:ffff:ffff:ffff
8028e0:4f0::/2828e0:4ff:ffff:ffff:ffff:ffff:ffff:ffff
8128e0:500::/2828e0:50f:ffff:ffff:ffff:ffff:ffff:ffff
8228e0:510::/2828e0:51f:ffff:ffff:ffff:ffff:ffff:ffff
8328e0:520::/2828e0:52f:ffff:ffff:ffff:ffff:ffff:ffff
8428e0:530::/2828e0:53f:ffff:ffff:ffff:ffff:ffff:ffff
8528e0:540::/2828e0:54f:ffff:ffff:ffff:ffff:ffff:ffff
8628e0:550::/2828e0:55f:ffff:ffff:ffff:ffff:ffff:ffff
8728e0:560::/2828e0:56f:ffff:ffff:ffff:ffff:ffff:ffff
8828e0:570::/2828e0:57f:ffff:ffff:ffff:ffff:ffff:ffff
8928e0:580::/2828e0:58f:ffff:ffff:ffff:ffff:ffff:ffff
9028e0:590::/2828e0:59f:ffff:ffff:ffff:ffff:ffff:ffff
9128e0:5a0::/2828e0:5af:ffff:ffff:ffff:ffff:ffff:ffff
9228e0:5b0::/2828e0:5bf:ffff:ffff:ffff:ffff:ffff:ffff
9328e0:5c0::/2828e0:5cf:ffff:ffff:ffff:ffff:ffff:ffff
9428e0:5d0::/2828e0:5df:ffff:ffff:ffff:ffff:ffff:ffff
9528e0:5e0::/2828e0:5ef:ffff:ffff:ffff:ffff:ffff:ffff
9628e0:5f0::/2828e0:5ff:ffff:ffff:ffff:ffff:ffff:ffff
9728e0:600::/2828e0:60f:ffff:ffff:ffff:ffff:ffff:ffff
9828e0:610::/2828e0:61f:ffff:ffff:ffff:ffff:ffff:ffff
9928e0:620::/2828e0:62f:ffff:ffff:ffff:ffff:ffff:ffff
10028e0:630::/2828e0:63f:ffff:ffff:ffff:ffff:ffff:ffff
10128e0:640::/2828e0:64f:ffff:ffff:ffff:ffff:ffff:ffff
10228e0:650::/2828e0:65f:ffff:ffff:ffff:ffff:ffff:ffff
10328e0:660::/2828e0:66f:ffff:ffff:ffff:ffff:ffff:ffff
10428e0:670::/2828e0:67f:ffff:ffff:ffff:ffff:ffff:ffff
10528e0:680::/2828e0:68f:ffff:ffff:ffff:ffff:ffff:ffff
10628e0:690::/2828e0:69f:ffff:ffff:ffff:ffff:ffff:ffff
10728e0:6a0::/2828e0:6af:ffff:ffff:ffff:ffff:ffff:ffff
10828e0:6b0::/2828e0:6bf:ffff:ffff:ffff:ffff:ffff:ffff
10928e0:6c0::/2828e0:6cf:ffff:ffff:ffff:ffff:ffff:ffff
11028e0:6d0::/2828e0:6df:ffff:ffff:ffff:ffff:ffff:ffff
11128e0:6e0::/2828e0:6ef:ffff:ffff:ffff:ffff:ffff:ffff
11228e0:6f0::/2828e0:6ff:ffff:ffff:ffff:ffff:ffff:ffff
11328e0:700::/2828e0:70f:ffff:ffff:ffff:ffff:ffff:ffff
11428e0:710::/2828e0:71f:ffff:ffff:ffff:ffff:ffff:ffff
11528e0:720::/2828e0:72f:ffff:ffff:ffff:ffff:ffff:ffff
11628e0:730::/2828e0:73f:ffff:ffff:ffff:ffff:ffff:ffff
11728e0:740::/2828e0:74f:ffff:ffff:ffff:ffff:ffff:ffff
11828e0:750::/2828e0:75f:ffff:ffff:ffff:ffff:ffff:ffff
11928e0:760::/2828e0:76f:ffff:ffff:ffff:ffff:ffff:ffff
12028e0:770::/2828e0:77f:ffff:ffff:ffff:ffff:ffff:ffff
12128e0:780::/2828e0:78f:ffff:ffff:ffff:ffff:ffff:ffff
12228e0:790::/2828e0:79f:ffff:ffff:ffff:ffff:ffff:ffff
12328e0:7a0::/2828e0:7af:ffff:ffff:ffff:ffff:ffff:ffff
12428e0:7b0::/2828e0:7bf:ffff:ffff:ffff:ffff:ffff:ffff
12528e0:7c0::/2828e0:7cf:ffff:ffff:ffff:ffff:ffff:ffff
12628e0:7d0::/2828e0:7df:ffff:ffff:ffff:ffff:ffff:ffff
12728e0:7e0::/2828e0:7ef:ffff:ffff:ffff:ffff:ffff:ffff
12828e0:7f0::/2828e0:7ff:ffff:ffff:ffff:ffff:ffff:ffff
12928e0:800::/2828e0:80f:ffff:ffff:ffff:ffff:ffff:ffff
13028e0:810::/2828e0:81f:ffff:ffff:ffff:ffff:ffff:ffff
13128e0:820::/2828e0:82f:ffff:ffff:ffff:ffff:ffff:ffff
13228e0:830::/2828e0:83f:ffff:ffff:ffff:ffff:ffff:ffff
13328e0:840::/2828e0:84f:ffff:ffff:ffff:ffff:ffff:ffff
13428e0:850::/2828e0:85f:ffff:ffff:ffff:ffff:ffff:ffff
13528e0:860::/2828e0:86f:ffff:ffff:ffff:ffff:ffff:ffff
13628e0:870::/2828e0:87f:ffff:ffff:ffff:ffff:ffff:ffff
13728e0:880::/2828e0:88f:ffff:ffff:ffff:ffff:ffff:ffff
13828e0:890::/2828e0:89f:ffff:ffff:ffff:ffff:ffff:ffff
13928e0:8a0::/2828e0:8af:ffff:ffff:ffff:ffff:ffff:ffff
14028e0:8b0::/2828e0:8bf:ffff:ffff:ffff:ffff:ffff:ffff
14128e0:8c0::/2828e0:8cf:ffff:ffff:ffff:ffff:ffff:ffff
14228e0:8d0::/2828e0:8df:ffff:ffff:ffff:ffff:ffff:ffff
14328e0:8e0::/2828e0:8ef:ffff:ffff:ffff:ffff:ffff:ffff
14428e0:8f0::/2828e0:8ff:ffff:ffff:ffff:ffff:ffff:ffff
14528e0:900::/2828e0:90f:ffff:ffff:ffff:ffff:ffff:ffff
14628e0:910::/2828e0:91f:ffff:ffff:ffff:ffff:ffff:ffff
14728e0:920::/2828e0:92f:ffff:ffff:ffff:ffff:ffff:ffff
14828e0:930::/2828e0:93f:ffff:ffff:ffff:ffff:ffff:ffff
14928e0:940::/2828e0:94f:ffff:ffff:ffff:ffff:ffff:ffff
15028e0:950::/2828e0:95f:ffff:ffff:ffff:ffff:ffff:ffff
15128e0:960::/2828e0:96f:ffff:ffff:ffff:ffff:ffff:ffff
15228e0:970::/2828e0:97f:ffff:ffff:ffff:ffff:ffff:ffff
15328e0:980::/2828e0:98f:ffff:ffff:ffff:ffff:ffff:ffff
15428e0:990::/2828e0:99f:ffff:ffff:ffff:ffff:ffff:ffff
15528e0:9a0::/2828e0:9af:ffff:ffff:ffff:ffff:ffff:ffff
15628e0:9b0::/2828e0:9bf:ffff:ffff:ffff:ffff:ffff:ffff
15728e0:9c0::/2828e0:9cf:ffff:ffff:ffff:ffff:ffff:ffff
15828e0:9d0::/2828e0:9df:ffff:ffff:ffff:ffff:ffff:ffff
15928e0:9e0::/2828e0:9ef:ffff:ffff:ffff:ffff:ffff:ffff
16028e0:9f0::/2828e0:9ff:ffff:ffff:ffff:ffff:ffff:ffff
16128e0:a00::/2828e0:a0f:ffff:ffff:ffff:ffff:ffff:ffff
16228e0:a10::/2828e0:a1f:ffff:ffff:ffff:ffff:ffff:ffff
16328e0:a20::/2828e0:a2f:ffff:ffff:ffff:ffff:ffff:ffff
16428e0:a30::/2828e0:a3f:ffff:ffff:ffff:ffff:ffff:ffff
16528e0:a40::/2828e0:a4f:ffff:ffff:ffff:ffff:ffff:ffff
16628e0:a50::/2828e0:a5f:ffff:ffff:ffff:ffff:ffff:ffff
16728e0:a60::/2828e0:a6f:ffff:ffff:ffff:ffff:ffff:ffff
16828e0:a70::/2828e0:a7f:ffff:ffff:ffff:ffff:ffff:ffff
16928e0:a80::/2828e0:a8f:ffff:ffff:ffff:ffff:ffff:ffff
17028e0:a90::/2828e0:a9f:ffff:ffff:ffff:ffff:ffff:ffff
17128e0:aa0::/2828e0:aaf:ffff:ffff:ffff:ffff:ffff:ffff
17228e0:ab0::/2828e0:abf:ffff:ffff:ffff:ffff:ffff:ffff
17328e0:ac0::/2828e0:acf:ffff:ffff:ffff:ffff:ffff:ffff
17428e0:ad0::/2828e0:adf:ffff:ffff:ffff:ffff:ffff:ffff
17528e0:ae0::/2828e0:aef:ffff:ffff:ffff:ffff:ffff:ffff
17628e0:af0::/2828e0:aff:ffff:ffff:ffff:ffff:ffff:ffff
17728e0:b00::/2828e0:b0f:ffff:ffff:ffff:ffff:ffff:ffff
17828e0:b10::/2828e0:b1f:ffff:ffff:ffff:ffff:ffff:ffff
17928e0:b20::/2828e0:b2f:ffff:ffff:ffff:ffff:ffff:ffff
18028e0:b30::/2828e0:b3f:ffff:ffff:ffff:ffff:ffff:ffff
18128e0:b40::/2828e0:b4f:ffff:ffff:ffff:ffff:ffff:ffff
18228e0:b50::/2828e0:b5f:ffff:ffff:ffff:ffff:ffff:ffff
18328e0:b60::/2828e0:b6f:ffff:ffff:ffff:ffff:ffff:ffff
18428e0:b70::/2828e0:b7f:ffff:ffff:ffff:ffff:ffff:ffff
18528e0:b80::/2828e0:b8f:ffff:ffff:ffff:ffff:ffff:ffff
18628e0:b90::/2828e0:b9f:ffff:ffff:ffff:ffff:ffff:ffff
18728e0:ba0::/2828e0:baf:ffff:ffff:ffff:ffff:ffff:ffff
18828e0:bb0::/2828e0:bbf:ffff:ffff:ffff:ffff:ffff:ffff
18928e0:bc0::/2828e0:bcf:ffff:ffff:ffff:ffff:ffff:ffff
19028e0:bd0::/2828e0:bdf:ffff:ffff:ffff:ffff:ffff:ffff
19128e0:be0::/2828e0:bef:ffff:ffff:ffff:ffff:ffff:ffff
19228e0:bf0::/2828e0:bff:ffff:ffff:ffff:ffff:ffff:ffff
19328e0:c00::/2828e0:c0f:ffff:ffff:ffff:ffff:ffff:ffff
19428e0:c10::/2828e0:c1f:ffff:ffff:ffff:ffff:ffff:ffff
19528e0:c20::/2828e0:c2f:ffff:ffff:ffff:ffff:ffff:ffff
19628e0:c30::/2828e0:c3f:ffff:ffff:ffff:ffff:ffff:ffff
19728e0:c40::/2828e0:c4f:ffff:ffff:ffff:ffff:ffff:ffff
19828e0:c50::/2828e0:c5f:ffff:ffff:ffff:ffff:ffff:ffff
19928e0:c60::/2828e0:c6f:ffff:ffff:ffff:ffff:ffff:ffff
20028e0:c70::/2828e0:c7f:ffff:ffff:ffff:ffff:ffff:ffff
20128e0:c80::/2828e0:c8f:ffff:ffff:ffff:ffff:ffff:ffff
20228e0:c90::/2828e0:c9f:ffff:ffff:ffff:ffff:ffff:ffff
20328e0:ca0::/2828e0:caf:ffff:ffff:ffff:ffff:ffff:ffff
20428e0:cb0::/2828e0:cbf:ffff:ffff:ffff:ffff:ffff:ffff
20528e0:cc0::/2828e0:ccf:ffff:ffff:ffff:ffff:ffff:ffff
20628e0:cd0::/2828e0:cdf:ffff:ffff:ffff:ffff:ffff:ffff
20728e0:ce0::/2828e0:cef:ffff:ffff:ffff:ffff:ffff:ffff
20828e0:cf0::/2828e0:cff:ffff:ffff:ffff:ffff:ffff:ffff
20928e0:d00::/2828e0:d0f:ffff:ffff:ffff:ffff:ffff:ffff
21028e0:d10::/2828e0:d1f:ffff:ffff:ffff:ffff:ffff:ffff
21128e0:d20::/2828e0:d2f:ffff:ffff:ffff:ffff:ffff:ffff
21228e0:d30::/2828e0:d3f:ffff:ffff:ffff:ffff:ffff:ffff
21328e0:d40::/2828e0:d4f:ffff:ffff:ffff:ffff:ffff:ffff
21428e0:d50::/2828e0:d5f:ffff:ffff:ffff:ffff:ffff:ffff
21528e0:d60::/2828e0:d6f:ffff:ffff:ffff:ffff:ffff:ffff
21628e0:d70::/2828e0:d7f:ffff:ffff:ffff:ffff:ffff:ffff
21728e0:d80::/2828e0:d8f:ffff:ffff:ffff:ffff:ffff:ffff
21828e0:d90::/2828e0:d9f:ffff:ffff:ffff:ffff:ffff:ffff
21928e0:da0::/2828e0:daf:ffff:ffff:ffff:ffff:ffff:ffff
22028e0:db0::/2828e0:dbf:ffff:ffff:ffff:ffff:ffff:ffff
22128e0:dc0::/2828e0:dcf:ffff:ffff:ffff:ffff:ffff:ffff
22228e0:dd0::/2828e0:ddf:ffff:ffff:ffff:ffff:ffff:ffff
22328e0:de0::/2828e0:def:ffff:ffff:ffff:ffff:ffff:ffff
22428e0:df0::/2828e0:dff:ffff:ffff:ffff:ffff:ffff:ffff
22528e0:e00::/2828e0:e0f:ffff:ffff:ffff:ffff:ffff:ffff
22628e0:e10::/2828e0:e1f:ffff:ffff:ffff:ffff:ffff:ffff
22728e0:e20::/2828e0:e2f:ffff:ffff:ffff:ffff:ffff:ffff
22828e0:e30::/2828e0:e3f:ffff:ffff:ffff:ffff:ffff:ffff
22928e0:e40::/2828e0:e4f:ffff:ffff:ffff:ffff:ffff:ffff
23028e0:e50::/2828e0:e5f:ffff:ffff:ffff:ffff:ffff:ffff
23128e0:e60::/2828e0:e6f:ffff:ffff:ffff:ffff:ffff:ffff
23228e0:e70::/2828e0:e7f:ffff:ffff:ffff:ffff:ffff:ffff
23328e0:e80::/2828e0:e8f:ffff:ffff:ffff:ffff:ffff:ffff
23428e0:e90::/2828e0:e9f:ffff:ffff:ffff:ffff:ffff:ffff
23528e0:ea0::/2828e0:eaf:ffff:ffff:ffff:ffff:ffff:ffff
23628e0:eb0::/2828e0:ebf:ffff:ffff:ffff:ffff:ffff:ffff
23728e0:ec0::/2828e0:ecf:ffff:ffff:ffff:ffff:ffff:ffff
23828e0:ed0::/2828e0:edf:ffff:ffff:ffff:ffff:ffff:ffff
23928e0:ee0::/2828e0:eef:ffff:ffff:ffff:ffff:ffff:ffff
24028e0:ef0::/2828e0:eff:ffff:ffff:ffff:ffff:ffff:ffff
24128e0:f00::/2828e0:f0f:ffff:ffff:ffff:ffff:ffff:ffff
24228e0:f10::/2828e0:f1f:ffff:ffff:ffff:ffff:ffff:ffff
24328e0:f20::/2828e0:f2f:ffff:ffff:ffff:ffff:ffff:ffff
24428e0:f30::/2828e0:f3f:ffff:ffff:ffff:ffff:ffff:ffff
24528e0:f40::/2828e0:f4f:ffff:ffff:ffff:ffff:ffff:ffff
24628e0:f50::/2828e0:f5f:ffff:ffff:ffff:ffff:ffff:ffff
24728e0:f60::/2828e0:f6f:ffff:ffff:ffff:ffff:ffff:ffff
24828e0:f70::/2828e0:f7f:ffff:ffff:ffff:ffff:ffff:ffff
24928e0:f80::/2828e0:f8f:ffff:ffff:ffff:ffff:ffff:ffff
25028e0:f90::/2828e0:f9f:ffff:ffff:ffff:ffff:ffff:ffff
25128e0:fa0::/2828e0:faf:ffff:ffff:ffff:ffff:ffff:ffff
25228e0:fb0::/2828e0:fbf:ffff:ffff:ffff:ffff:ffff:ffff
25328e0:fc0::/2828e0:fcf:ffff:ffff:ffff:ffff:ffff:ffff
25428e0:fd0::/2828e0:fdf:ffff:ffff:ffff:ffff:ffff:ffff
25528e0:fe0::/2828e0:fef:ffff:ffff:ffff:ffff:ffff:ffff
25628e0:ff0::/2828e0:fff: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.