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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
22e0::/12
First address
22e0::
Last address
22ef: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
22e0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.2.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

22e0::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
122e0::/2822e0:f:ffff:ffff:ffff:ffff:ffff:ffff
222e0:10::/2822e0:1f:ffff:ffff:ffff:ffff:ffff:ffff
322e0:20::/2822e0:2f:ffff:ffff:ffff:ffff:ffff:ffff
422e0:30::/2822e0:3f:ffff:ffff:ffff:ffff:ffff:ffff
522e0:40::/2822e0:4f:ffff:ffff:ffff:ffff:ffff:ffff
622e0:50::/2822e0:5f:ffff:ffff:ffff:ffff:ffff:ffff
722e0:60::/2822e0:6f:ffff:ffff:ffff:ffff:ffff:ffff
822e0:70::/2822e0:7f:ffff:ffff:ffff:ffff:ffff:ffff
922e0:80::/2822e0:8f:ffff:ffff:ffff:ffff:ffff:ffff
1022e0:90::/2822e0:9f:ffff:ffff:ffff:ffff:ffff:ffff
1122e0:a0::/2822e0:af:ffff:ffff:ffff:ffff:ffff:ffff
1222e0:b0::/2822e0:bf:ffff:ffff:ffff:ffff:ffff:ffff
1322e0:c0::/2822e0:cf:ffff:ffff:ffff:ffff:ffff:ffff
1422e0:d0::/2822e0:df:ffff:ffff:ffff:ffff:ffff:ffff
1522e0:e0::/2822e0:ef:ffff:ffff:ffff:ffff:ffff:ffff
1622e0:f0::/2822e0:ff:ffff:ffff:ffff:ffff:ffff:ffff
1722e0:100::/2822e0:10f:ffff:ffff:ffff:ffff:ffff:ffff
1822e0:110::/2822e0:11f:ffff:ffff:ffff:ffff:ffff:ffff
1922e0:120::/2822e0:12f:ffff:ffff:ffff:ffff:ffff:ffff
2022e0:130::/2822e0:13f:ffff:ffff:ffff:ffff:ffff:ffff
2122e0:140::/2822e0:14f:ffff:ffff:ffff:ffff:ffff:ffff
2222e0:150::/2822e0:15f:ffff:ffff:ffff:ffff:ffff:ffff
2322e0:160::/2822e0:16f:ffff:ffff:ffff:ffff:ffff:ffff
2422e0:170::/2822e0:17f:ffff:ffff:ffff:ffff:ffff:ffff
2522e0:180::/2822e0:18f:ffff:ffff:ffff:ffff:ffff:ffff
2622e0:190::/2822e0:19f:ffff:ffff:ffff:ffff:ffff:ffff
2722e0:1a0::/2822e0:1af:ffff:ffff:ffff:ffff:ffff:ffff
2822e0:1b0::/2822e0:1bf:ffff:ffff:ffff:ffff:ffff:ffff
2922e0:1c0::/2822e0:1cf:ffff:ffff:ffff:ffff:ffff:ffff
3022e0:1d0::/2822e0:1df:ffff:ffff:ffff:ffff:ffff:ffff
3122e0:1e0::/2822e0:1ef:ffff:ffff:ffff:ffff:ffff:ffff
3222e0:1f0::/2822e0:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3322e0:200::/2822e0:20f:ffff:ffff:ffff:ffff:ffff:ffff
3422e0:210::/2822e0:21f:ffff:ffff:ffff:ffff:ffff:ffff
3522e0:220::/2822e0:22f:ffff:ffff:ffff:ffff:ffff:ffff
3622e0:230::/2822e0:23f:ffff:ffff:ffff:ffff:ffff:ffff
3722e0:240::/2822e0:24f:ffff:ffff:ffff:ffff:ffff:ffff
3822e0:250::/2822e0:25f:ffff:ffff:ffff:ffff:ffff:ffff
3922e0:260::/2822e0:26f:ffff:ffff:ffff:ffff:ffff:ffff
4022e0:270::/2822e0:27f:ffff:ffff:ffff:ffff:ffff:ffff
4122e0:280::/2822e0:28f:ffff:ffff:ffff:ffff:ffff:ffff
4222e0:290::/2822e0:29f:ffff:ffff:ffff:ffff:ffff:ffff
4322e0:2a0::/2822e0:2af:ffff:ffff:ffff:ffff:ffff:ffff
4422e0:2b0::/2822e0:2bf:ffff:ffff:ffff:ffff:ffff:ffff
4522e0:2c0::/2822e0:2cf:ffff:ffff:ffff:ffff:ffff:ffff
4622e0:2d0::/2822e0:2df:ffff:ffff:ffff:ffff:ffff:ffff
4722e0:2e0::/2822e0:2ef:ffff:ffff:ffff:ffff:ffff:ffff
4822e0:2f0::/2822e0:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4922e0:300::/2822e0:30f:ffff:ffff:ffff:ffff:ffff:ffff
5022e0:310::/2822e0:31f:ffff:ffff:ffff:ffff:ffff:ffff
5122e0:320::/2822e0:32f:ffff:ffff:ffff:ffff:ffff:ffff
5222e0:330::/2822e0:33f:ffff:ffff:ffff:ffff:ffff:ffff
5322e0:340::/2822e0:34f:ffff:ffff:ffff:ffff:ffff:ffff
5422e0:350::/2822e0:35f:ffff:ffff:ffff:ffff:ffff:ffff
5522e0:360::/2822e0:36f:ffff:ffff:ffff:ffff:ffff:ffff
5622e0:370::/2822e0:37f:ffff:ffff:ffff:ffff:ffff:ffff
5722e0:380::/2822e0:38f:ffff:ffff:ffff:ffff:ffff:ffff
5822e0:390::/2822e0:39f:ffff:ffff:ffff:ffff:ffff:ffff
5922e0:3a0::/2822e0:3af:ffff:ffff:ffff:ffff:ffff:ffff
6022e0:3b0::/2822e0:3bf:ffff:ffff:ffff:ffff:ffff:ffff
6122e0:3c0::/2822e0:3cf:ffff:ffff:ffff:ffff:ffff:ffff
6222e0:3d0::/2822e0:3df:ffff:ffff:ffff:ffff:ffff:ffff
6322e0:3e0::/2822e0:3ef:ffff:ffff:ffff:ffff:ffff:ffff
6422e0:3f0::/2822e0:3ff:ffff:ffff:ffff:ffff:ffff:ffff
6522e0:400::/2822e0:40f:ffff:ffff:ffff:ffff:ffff:ffff
6622e0:410::/2822e0:41f:ffff:ffff:ffff:ffff:ffff:ffff
6722e0:420::/2822e0:42f:ffff:ffff:ffff:ffff:ffff:ffff
6822e0:430::/2822e0:43f:ffff:ffff:ffff:ffff:ffff:ffff
6922e0:440::/2822e0:44f:ffff:ffff:ffff:ffff:ffff:ffff
7022e0:450::/2822e0:45f:ffff:ffff:ffff:ffff:ffff:ffff
7122e0:460::/2822e0:46f:ffff:ffff:ffff:ffff:ffff:ffff
7222e0:470::/2822e0:47f:ffff:ffff:ffff:ffff:ffff:ffff
7322e0:480::/2822e0:48f:ffff:ffff:ffff:ffff:ffff:ffff
7422e0:490::/2822e0:49f:ffff:ffff:ffff:ffff:ffff:ffff
7522e0:4a0::/2822e0:4af:ffff:ffff:ffff:ffff:ffff:ffff
7622e0:4b0::/2822e0:4bf:ffff:ffff:ffff:ffff:ffff:ffff
7722e0:4c0::/2822e0:4cf:ffff:ffff:ffff:ffff:ffff:ffff
7822e0:4d0::/2822e0:4df:ffff:ffff:ffff:ffff:ffff:ffff
7922e0:4e0::/2822e0:4ef:ffff:ffff:ffff:ffff:ffff:ffff
8022e0:4f0::/2822e0:4ff:ffff:ffff:ffff:ffff:ffff:ffff
8122e0:500::/2822e0:50f:ffff:ffff:ffff:ffff:ffff:ffff
8222e0:510::/2822e0:51f:ffff:ffff:ffff:ffff:ffff:ffff
8322e0:520::/2822e0:52f:ffff:ffff:ffff:ffff:ffff:ffff
8422e0:530::/2822e0:53f:ffff:ffff:ffff:ffff:ffff:ffff
8522e0:540::/2822e0:54f:ffff:ffff:ffff:ffff:ffff:ffff
8622e0:550::/2822e0:55f:ffff:ffff:ffff:ffff:ffff:ffff
8722e0:560::/2822e0:56f:ffff:ffff:ffff:ffff:ffff:ffff
8822e0:570::/2822e0:57f:ffff:ffff:ffff:ffff:ffff:ffff
8922e0:580::/2822e0:58f:ffff:ffff:ffff:ffff:ffff:ffff
9022e0:590::/2822e0:59f:ffff:ffff:ffff:ffff:ffff:ffff
9122e0:5a0::/2822e0:5af:ffff:ffff:ffff:ffff:ffff:ffff
9222e0:5b0::/2822e0:5bf:ffff:ffff:ffff:ffff:ffff:ffff
9322e0:5c0::/2822e0:5cf:ffff:ffff:ffff:ffff:ffff:ffff
9422e0:5d0::/2822e0:5df:ffff:ffff:ffff:ffff:ffff:ffff
9522e0:5e0::/2822e0:5ef:ffff:ffff:ffff:ffff:ffff:ffff
9622e0:5f0::/2822e0:5ff:ffff:ffff:ffff:ffff:ffff:ffff
9722e0:600::/2822e0:60f:ffff:ffff:ffff:ffff:ffff:ffff
9822e0:610::/2822e0:61f:ffff:ffff:ffff:ffff:ffff:ffff
9922e0:620::/2822e0:62f:ffff:ffff:ffff:ffff:ffff:ffff
10022e0:630::/2822e0:63f:ffff:ffff:ffff:ffff:ffff:ffff
10122e0:640::/2822e0:64f:ffff:ffff:ffff:ffff:ffff:ffff
10222e0:650::/2822e0:65f:ffff:ffff:ffff:ffff:ffff:ffff
10322e0:660::/2822e0:66f:ffff:ffff:ffff:ffff:ffff:ffff
10422e0:670::/2822e0:67f:ffff:ffff:ffff:ffff:ffff:ffff
10522e0:680::/2822e0:68f:ffff:ffff:ffff:ffff:ffff:ffff
10622e0:690::/2822e0:69f:ffff:ffff:ffff:ffff:ffff:ffff
10722e0:6a0::/2822e0:6af:ffff:ffff:ffff:ffff:ffff:ffff
10822e0:6b0::/2822e0:6bf:ffff:ffff:ffff:ffff:ffff:ffff
10922e0:6c0::/2822e0:6cf:ffff:ffff:ffff:ffff:ffff:ffff
11022e0:6d0::/2822e0:6df:ffff:ffff:ffff:ffff:ffff:ffff
11122e0:6e0::/2822e0:6ef:ffff:ffff:ffff:ffff:ffff:ffff
11222e0:6f0::/2822e0:6ff:ffff:ffff:ffff:ffff:ffff:ffff
11322e0:700::/2822e0:70f:ffff:ffff:ffff:ffff:ffff:ffff
11422e0:710::/2822e0:71f:ffff:ffff:ffff:ffff:ffff:ffff
11522e0:720::/2822e0:72f:ffff:ffff:ffff:ffff:ffff:ffff
11622e0:730::/2822e0:73f:ffff:ffff:ffff:ffff:ffff:ffff
11722e0:740::/2822e0:74f:ffff:ffff:ffff:ffff:ffff:ffff
11822e0:750::/2822e0:75f:ffff:ffff:ffff:ffff:ffff:ffff
11922e0:760::/2822e0:76f:ffff:ffff:ffff:ffff:ffff:ffff
12022e0:770::/2822e0:77f:ffff:ffff:ffff:ffff:ffff:ffff
12122e0:780::/2822e0:78f:ffff:ffff:ffff:ffff:ffff:ffff
12222e0:790::/2822e0:79f:ffff:ffff:ffff:ffff:ffff:ffff
12322e0:7a0::/2822e0:7af:ffff:ffff:ffff:ffff:ffff:ffff
12422e0:7b0::/2822e0:7bf:ffff:ffff:ffff:ffff:ffff:ffff
12522e0:7c0::/2822e0:7cf:ffff:ffff:ffff:ffff:ffff:ffff
12622e0:7d0::/2822e0:7df:ffff:ffff:ffff:ffff:ffff:ffff
12722e0:7e0::/2822e0:7ef:ffff:ffff:ffff:ffff:ffff:ffff
12822e0:7f0::/2822e0:7ff:ffff:ffff:ffff:ffff:ffff:ffff
12922e0:800::/2822e0:80f:ffff:ffff:ffff:ffff:ffff:ffff
13022e0:810::/2822e0:81f:ffff:ffff:ffff:ffff:ffff:ffff
13122e0:820::/2822e0:82f:ffff:ffff:ffff:ffff:ffff:ffff
13222e0:830::/2822e0:83f:ffff:ffff:ffff:ffff:ffff:ffff
13322e0:840::/2822e0:84f:ffff:ffff:ffff:ffff:ffff:ffff
13422e0:850::/2822e0:85f:ffff:ffff:ffff:ffff:ffff:ffff
13522e0:860::/2822e0:86f:ffff:ffff:ffff:ffff:ffff:ffff
13622e0:870::/2822e0:87f:ffff:ffff:ffff:ffff:ffff:ffff
13722e0:880::/2822e0:88f:ffff:ffff:ffff:ffff:ffff:ffff
13822e0:890::/2822e0:89f:ffff:ffff:ffff:ffff:ffff:ffff
13922e0:8a0::/2822e0:8af:ffff:ffff:ffff:ffff:ffff:ffff
14022e0:8b0::/2822e0:8bf:ffff:ffff:ffff:ffff:ffff:ffff
14122e0:8c0::/2822e0:8cf:ffff:ffff:ffff:ffff:ffff:ffff
14222e0:8d0::/2822e0:8df:ffff:ffff:ffff:ffff:ffff:ffff
14322e0:8e0::/2822e0:8ef:ffff:ffff:ffff:ffff:ffff:ffff
14422e0:8f0::/2822e0:8ff:ffff:ffff:ffff:ffff:ffff:ffff
14522e0:900::/2822e0:90f:ffff:ffff:ffff:ffff:ffff:ffff
14622e0:910::/2822e0:91f:ffff:ffff:ffff:ffff:ffff:ffff
14722e0:920::/2822e0:92f:ffff:ffff:ffff:ffff:ffff:ffff
14822e0:930::/2822e0:93f:ffff:ffff:ffff:ffff:ffff:ffff
14922e0:940::/2822e0:94f:ffff:ffff:ffff:ffff:ffff:ffff
15022e0:950::/2822e0:95f:ffff:ffff:ffff:ffff:ffff:ffff
15122e0:960::/2822e0:96f:ffff:ffff:ffff:ffff:ffff:ffff
15222e0:970::/2822e0:97f:ffff:ffff:ffff:ffff:ffff:ffff
15322e0:980::/2822e0:98f:ffff:ffff:ffff:ffff:ffff:ffff
15422e0:990::/2822e0:99f:ffff:ffff:ffff:ffff:ffff:ffff
15522e0:9a0::/2822e0:9af:ffff:ffff:ffff:ffff:ffff:ffff
15622e0:9b0::/2822e0:9bf:ffff:ffff:ffff:ffff:ffff:ffff
15722e0:9c0::/2822e0:9cf:ffff:ffff:ffff:ffff:ffff:ffff
15822e0:9d0::/2822e0:9df:ffff:ffff:ffff:ffff:ffff:ffff
15922e0:9e0::/2822e0:9ef:ffff:ffff:ffff:ffff:ffff:ffff
16022e0:9f0::/2822e0:9ff:ffff:ffff:ffff:ffff:ffff:ffff
16122e0:a00::/2822e0:a0f:ffff:ffff:ffff:ffff:ffff:ffff
16222e0:a10::/2822e0:a1f:ffff:ffff:ffff:ffff:ffff:ffff
16322e0:a20::/2822e0:a2f:ffff:ffff:ffff:ffff:ffff:ffff
16422e0:a30::/2822e0:a3f:ffff:ffff:ffff:ffff:ffff:ffff
16522e0:a40::/2822e0:a4f:ffff:ffff:ffff:ffff:ffff:ffff
16622e0:a50::/2822e0:a5f:ffff:ffff:ffff:ffff:ffff:ffff
16722e0:a60::/2822e0:a6f:ffff:ffff:ffff:ffff:ffff:ffff
16822e0:a70::/2822e0:a7f:ffff:ffff:ffff:ffff:ffff:ffff
16922e0:a80::/2822e0:a8f:ffff:ffff:ffff:ffff:ffff:ffff
17022e0:a90::/2822e0:a9f:ffff:ffff:ffff:ffff:ffff:ffff
17122e0:aa0::/2822e0:aaf:ffff:ffff:ffff:ffff:ffff:ffff
17222e0:ab0::/2822e0:abf:ffff:ffff:ffff:ffff:ffff:ffff
17322e0:ac0::/2822e0:acf:ffff:ffff:ffff:ffff:ffff:ffff
17422e0:ad0::/2822e0:adf:ffff:ffff:ffff:ffff:ffff:ffff
17522e0:ae0::/2822e0:aef:ffff:ffff:ffff:ffff:ffff:ffff
17622e0:af0::/2822e0:aff:ffff:ffff:ffff:ffff:ffff:ffff
17722e0:b00::/2822e0:b0f:ffff:ffff:ffff:ffff:ffff:ffff
17822e0:b10::/2822e0:b1f:ffff:ffff:ffff:ffff:ffff:ffff
17922e0:b20::/2822e0:b2f:ffff:ffff:ffff:ffff:ffff:ffff
18022e0:b30::/2822e0:b3f:ffff:ffff:ffff:ffff:ffff:ffff
18122e0:b40::/2822e0:b4f:ffff:ffff:ffff:ffff:ffff:ffff
18222e0:b50::/2822e0:b5f:ffff:ffff:ffff:ffff:ffff:ffff
18322e0:b60::/2822e0:b6f:ffff:ffff:ffff:ffff:ffff:ffff
18422e0:b70::/2822e0:b7f:ffff:ffff:ffff:ffff:ffff:ffff
18522e0:b80::/2822e0:b8f:ffff:ffff:ffff:ffff:ffff:ffff
18622e0:b90::/2822e0:b9f:ffff:ffff:ffff:ffff:ffff:ffff
18722e0:ba0::/2822e0:baf:ffff:ffff:ffff:ffff:ffff:ffff
18822e0:bb0::/2822e0:bbf:ffff:ffff:ffff:ffff:ffff:ffff
18922e0:bc0::/2822e0:bcf:ffff:ffff:ffff:ffff:ffff:ffff
19022e0:bd0::/2822e0:bdf:ffff:ffff:ffff:ffff:ffff:ffff
19122e0:be0::/2822e0:bef:ffff:ffff:ffff:ffff:ffff:ffff
19222e0:bf0::/2822e0:bff:ffff:ffff:ffff:ffff:ffff:ffff
19322e0:c00::/2822e0:c0f:ffff:ffff:ffff:ffff:ffff:ffff
19422e0:c10::/2822e0:c1f:ffff:ffff:ffff:ffff:ffff:ffff
19522e0:c20::/2822e0:c2f:ffff:ffff:ffff:ffff:ffff:ffff
19622e0:c30::/2822e0:c3f:ffff:ffff:ffff:ffff:ffff:ffff
19722e0:c40::/2822e0:c4f:ffff:ffff:ffff:ffff:ffff:ffff
19822e0:c50::/2822e0:c5f:ffff:ffff:ffff:ffff:ffff:ffff
19922e0:c60::/2822e0:c6f:ffff:ffff:ffff:ffff:ffff:ffff
20022e0:c70::/2822e0:c7f:ffff:ffff:ffff:ffff:ffff:ffff
20122e0:c80::/2822e0:c8f:ffff:ffff:ffff:ffff:ffff:ffff
20222e0:c90::/2822e0:c9f:ffff:ffff:ffff:ffff:ffff:ffff
20322e0:ca0::/2822e0:caf:ffff:ffff:ffff:ffff:ffff:ffff
20422e0:cb0::/2822e0:cbf:ffff:ffff:ffff:ffff:ffff:ffff
20522e0:cc0::/2822e0:ccf:ffff:ffff:ffff:ffff:ffff:ffff
20622e0:cd0::/2822e0:cdf:ffff:ffff:ffff:ffff:ffff:ffff
20722e0:ce0::/2822e0:cef:ffff:ffff:ffff:ffff:ffff:ffff
20822e0:cf0::/2822e0:cff:ffff:ffff:ffff:ffff:ffff:ffff
20922e0:d00::/2822e0:d0f:ffff:ffff:ffff:ffff:ffff:ffff
21022e0:d10::/2822e0:d1f:ffff:ffff:ffff:ffff:ffff:ffff
21122e0:d20::/2822e0:d2f:ffff:ffff:ffff:ffff:ffff:ffff
21222e0:d30::/2822e0:d3f:ffff:ffff:ffff:ffff:ffff:ffff
21322e0:d40::/2822e0:d4f:ffff:ffff:ffff:ffff:ffff:ffff
21422e0:d50::/2822e0:d5f:ffff:ffff:ffff:ffff:ffff:ffff
21522e0:d60::/2822e0:d6f:ffff:ffff:ffff:ffff:ffff:ffff
21622e0:d70::/2822e0:d7f:ffff:ffff:ffff:ffff:ffff:ffff
21722e0:d80::/2822e0:d8f:ffff:ffff:ffff:ffff:ffff:ffff
21822e0:d90::/2822e0:d9f:ffff:ffff:ffff:ffff:ffff:ffff
21922e0:da0::/2822e0:daf:ffff:ffff:ffff:ffff:ffff:ffff
22022e0:db0::/2822e0:dbf:ffff:ffff:ffff:ffff:ffff:ffff
22122e0:dc0::/2822e0:dcf:ffff:ffff:ffff:ffff:ffff:ffff
22222e0:dd0::/2822e0:ddf:ffff:ffff:ffff:ffff:ffff:ffff
22322e0:de0::/2822e0:def:ffff:ffff:ffff:ffff:ffff:ffff
22422e0:df0::/2822e0:dff:ffff:ffff:ffff:ffff:ffff:ffff
22522e0:e00::/2822e0:e0f:ffff:ffff:ffff:ffff:ffff:ffff
22622e0:e10::/2822e0:e1f:ffff:ffff:ffff:ffff:ffff:ffff
22722e0:e20::/2822e0:e2f:ffff:ffff:ffff:ffff:ffff:ffff
22822e0:e30::/2822e0:e3f:ffff:ffff:ffff:ffff:ffff:ffff
22922e0:e40::/2822e0:e4f:ffff:ffff:ffff:ffff:ffff:ffff
23022e0:e50::/2822e0:e5f:ffff:ffff:ffff:ffff:ffff:ffff
23122e0:e60::/2822e0:e6f:ffff:ffff:ffff:ffff:ffff:ffff
23222e0:e70::/2822e0:e7f:ffff:ffff:ffff:ffff:ffff:ffff
23322e0:e80::/2822e0:e8f:ffff:ffff:ffff:ffff:ffff:ffff
23422e0:e90::/2822e0:e9f:ffff:ffff:ffff:ffff:ffff:ffff
23522e0:ea0::/2822e0:eaf:ffff:ffff:ffff:ffff:ffff:ffff
23622e0:eb0::/2822e0:ebf:ffff:ffff:ffff:ffff:ffff:ffff
23722e0:ec0::/2822e0:ecf:ffff:ffff:ffff:ffff:ffff:ffff
23822e0:ed0::/2822e0:edf:ffff:ffff:ffff:ffff:ffff:ffff
23922e0:ee0::/2822e0:eef:ffff:ffff:ffff:ffff:ffff:ffff
24022e0:ef0::/2822e0:eff:ffff:ffff:ffff:ffff:ffff:ffff
24122e0:f00::/2822e0:f0f:ffff:ffff:ffff:ffff:ffff:ffff
24222e0:f10::/2822e0:f1f:ffff:ffff:ffff:ffff:ffff:ffff
24322e0:f20::/2822e0:f2f:ffff:ffff:ffff:ffff:ffff:ffff
24422e0:f30::/2822e0:f3f:ffff:ffff:ffff:ffff:ffff:ffff
24522e0:f40::/2822e0:f4f:ffff:ffff:ffff:ffff:ffff:ffff
24622e0:f50::/2822e0:f5f:ffff:ffff:ffff:ffff:ffff:ffff
24722e0:f60::/2822e0:f6f:ffff:ffff:ffff:ffff:ffff:ffff
24822e0:f70::/2822e0:f7f:ffff:ffff:ffff:ffff:ffff:ffff
24922e0:f80::/2822e0:f8f:ffff:ffff:ffff:ffff:ffff:ffff
25022e0:f90::/2822e0:f9f:ffff:ffff:ffff:ffff:ffff:ffff
25122e0:fa0::/2822e0:faf:ffff:ffff:ffff:ffff:ffff:ffff
25222e0:fb0::/2822e0:fbf:ffff:ffff:ffff:ffff:ffff:ffff
25322e0:fc0::/2822e0:fcf:ffff:ffff:ffff:ffff:ffff:ffff
25422e0:fd0::/2822e0:fdf:ffff:ffff:ffff:ffff:ffff:ffff
25522e0:fe0::/2822e0:fef:ffff:ffff:ffff:ffff:ffff:ffff
25622e0:ff0::/2822e0: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.