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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/16
Addresses2^112
/64 networks2^48
Network
28ea::/16
First address
28ea::
Last address
28ea:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
28ea:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.e.8.2.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

28ea::/16 makes 4,096 subnets of /28; the first 256 are listed.

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