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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
29a0::/12
First address
29a0::
Last address
29af: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
29a0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.9.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

29a0::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
129a0::/2829a0:f:ffff:ffff:ffff:ffff:ffff:ffff
229a0:10::/2829a0:1f:ffff:ffff:ffff:ffff:ffff:ffff
329a0:20::/2829a0:2f:ffff:ffff:ffff:ffff:ffff:ffff
429a0:30::/2829a0:3f:ffff:ffff:ffff:ffff:ffff:ffff
529a0:40::/2829a0:4f:ffff:ffff:ffff:ffff:ffff:ffff
629a0:50::/2829a0:5f:ffff:ffff:ffff:ffff:ffff:ffff
729a0:60::/2829a0:6f:ffff:ffff:ffff:ffff:ffff:ffff
829a0:70::/2829a0:7f:ffff:ffff:ffff:ffff:ffff:ffff
929a0:80::/2829a0:8f:ffff:ffff:ffff:ffff:ffff:ffff
1029a0:90::/2829a0:9f:ffff:ffff:ffff:ffff:ffff:ffff
1129a0:a0::/2829a0:af:ffff:ffff:ffff:ffff:ffff:ffff
1229a0:b0::/2829a0:bf:ffff:ffff:ffff:ffff:ffff:ffff
1329a0:c0::/2829a0:cf:ffff:ffff:ffff:ffff:ffff:ffff
1429a0:d0::/2829a0:df:ffff:ffff:ffff:ffff:ffff:ffff
1529a0:e0::/2829a0:ef:ffff:ffff:ffff:ffff:ffff:ffff
1629a0:f0::/2829a0:ff:ffff:ffff:ffff:ffff:ffff:ffff
1729a0:100::/2829a0:10f:ffff:ffff:ffff:ffff:ffff:ffff
1829a0:110::/2829a0:11f:ffff:ffff:ffff:ffff:ffff:ffff
1929a0:120::/2829a0:12f:ffff:ffff:ffff:ffff:ffff:ffff
2029a0:130::/2829a0:13f:ffff:ffff:ffff:ffff:ffff:ffff
2129a0:140::/2829a0:14f:ffff:ffff:ffff:ffff:ffff:ffff
2229a0:150::/2829a0:15f:ffff:ffff:ffff:ffff:ffff:ffff
2329a0:160::/2829a0:16f:ffff:ffff:ffff:ffff:ffff:ffff
2429a0:170::/2829a0:17f:ffff:ffff:ffff:ffff:ffff:ffff
2529a0:180::/2829a0:18f:ffff:ffff:ffff:ffff:ffff:ffff
2629a0:190::/2829a0:19f:ffff:ffff:ffff:ffff:ffff:ffff
2729a0:1a0::/2829a0:1af:ffff:ffff:ffff:ffff:ffff:ffff
2829a0:1b0::/2829a0:1bf:ffff:ffff:ffff:ffff:ffff:ffff
2929a0:1c0::/2829a0:1cf:ffff:ffff:ffff:ffff:ffff:ffff
3029a0:1d0::/2829a0:1df:ffff:ffff:ffff:ffff:ffff:ffff
3129a0:1e0::/2829a0:1ef:ffff:ffff:ffff:ffff:ffff:ffff
3229a0:1f0::/2829a0:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3329a0:200::/2829a0:20f:ffff:ffff:ffff:ffff:ffff:ffff
3429a0:210::/2829a0:21f:ffff:ffff:ffff:ffff:ffff:ffff
3529a0:220::/2829a0:22f:ffff:ffff:ffff:ffff:ffff:ffff
3629a0:230::/2829a0:23f:ffff:ffff:ffff:ffff:ffff:ffff
3729a0:240::/2829a0:24f:ffff:ffff:ffff:ffff:ffff:ffff
3829a0:250::/2829a0:25f:ffff:ffff:ffff:ffff:ffff:ffff
3929a0:260::/2829a0:26f:ffff:ffff:ffff:ffff:ffff:ffff
4029a0:270::/2829a0:27f:ffff:ffff:ffff:ffff:ffff:ffff
4129a0:280::/2829a0:28f:ffff:ffff:ffff:ffff:ffff:ffff
4229a0:290::/2829a0:29f:ffff:ffff:ffff:ffff:ffff:ffff
4329a0:2a0::/2829a0:2af:ffff:ffff:ffff:ffff:ffff:ffff
4429a0:2b0::/2829a0:2bf:ffff:ffff:ffff:ffff:ffff:ffff
4529a0:2c0::/2829a0:2cf:ffff:ffff:ffff:ffff:ffff:ffff
4629a0:2d0::/2829a0:2df:ffff:ffff:ffff:ffff:ffff:ffff
4729a0:2e0::/2829a0:2ef:ffff:ffff:ffff:ffff:ffff:ffff
4829a0:2f0::/2829a0:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4929a0:300::/2829a0:30f:ffff:ffff:ffff:ffff:ffff:ffff
5029a0:310::/2829a0:31f:ffff:ffff:ffff:ffff:ffff:ffff
5129a0:320::/2829a0:32f:ffff:ffff:ffff:ffff:ffff:ffff
5229a0:330::/2829a0:33f:ffff:ffff:ffff:ffff:ffff:ffff
5329a0:340::/2829a0:34f:ffff:ffff:ffff:ffff:ffff:ffff
5429a0:350::/2829a0:35f:ffff:ffff:ffff:ffff:ffff:ffff
5529a0:360::/2829a0:36f:ffff:ffff:ffff:ffff:ffff:ffff
5629a0:370::/2829a0:37f:ffff:ffff:ffff:ffff:ffff:ffff
5729a0:380::/2829a0:38f:ffff:ffff:ffff:ffff:ffff:ffff
5829a0:390::/2829a0:39f:ffff:ffff:ffff:ffff:ffff:ffff
5929a0:3a0::/2829a0:3af:ffff:ffff:ffff:ffff:ffff:ffff
6029a0:3b0::/2829a0:3bf:ffff:ffff:ffff:ffff:ffff:ffff
6129a0:3c0::/2829a0:3cf:ffff:ffff:ffff:ffff:ffff:ffff
6229a0:3d0::/2829a0:3df:ffff:ffff:ffff:ffff:ffff:ffff
6329a0:3e0::/2829a0:3ef:ffff:ffff:ffff:ffff:ffff:ffff
6429a0:3f0::/2829a0:3ff:ffff:ffff:ffff:ffff:ffff:ffff
6529a0:400::/2829a0:40f:ffff:ffff:ffff:ffff:ffff:ffff
6629a0:410::/2829a0:41f:ffff:ffff:ffff:ffff:ffff:ffff
6729a0:420::/2829a0:42f:ffff:ffff:ffff:ffff:ffff:ffff
6829a0:430::/2829a0:43f:ffff:ffff:ffff:ffff:ffff:ffff
6929a0:440::/2829a0:44f:ffff:ffff:ffff:ffff:ffff:ffff
7029a0:450::/2829a0:45f:ffff:ffff:ffff:ffff:ffff:ffff
7129a0:460::/2829a0:46f:ffff:ffff:ffff:ffff:ffff:ffff
7229a0:470::/2829a0:47f:ffff:ffff:ffff:ffff:ffff:ffff
7329a0:480::/2829a0:48f:ffff:ffff:ffff:ffff:ffff:ffff
7429a0:490::/2829a0:49f:ffff:ffff:ffff:ffff:ffff:ffff
7529a0:4a0::/2829a0:4af:ffff:ffff:ffff:ffff:ffff:ffff
7629a0:4b0::/2829a0:4bf:ffff:ffff:ffff:ffff:ffff:ffff
7729a0:4c0::/2829a0:4cf:ffff:ffff:ffff:ffff:ffff:ffff
7829a0:4d0::/2829a0:4df:ffff:ffff:ffff:ffff:ffff:ffff
7929a0:4e0::/2829a0:4ef:ffff:ffff:ffff:ffff:ffff:ffff
8029a0:4f0::/2829a0:4ff:ffff:ffff:ffff:ffff:ffff:ffff
8129a0:500::/2829a0:50f:ffff:ffff:ffff:ffff:ffff:ffff
8229a0:510::/2829a0:51f:ffff:ffff:ffff:ffff:ffff:ffff
8329a0:520::/2829a0:52f:ffff:ffff:ffff:ffff:ffff:ffff
8429a0:530::/2829a0:53f:ffff:ffff:ffff:ffff:ffff:ffff
8529a0:540::/2829a0:54f:ffff:ffff:ffff:ffff:ffff:ffff
8629a0:550::/2829a0:55f:ffff:ffff:ffff:ffff:ffff:ffff
8729a0:560::/2829a0:56f:ffff:ffff:ffff:ffff:ffff:ffff
8829a0:570::/2829a0:57f:ffff:ffff:ffff:ffff:ffff:ffff
8929a0:580::/2829a0:58f:ffff:ffff:ffff:ffff:ffff:ffff
9029a0:590::/2829a0:59f:ffff:ffff:ffff:ffff:ffff:ffff
9129a0:5a0::/2829a0:5af:ffff:ffff:ffff:ffff:ffff:ffff
9229a0:5b0::/2829a0:5bf:ffff:ffff:ffff:ffff:ffff:ffff
9329a0:5c0::/2829a0:5cf:ffff:ffff:ffff:ffff:ffff:ffff
9429a0:5d0::/2829a0:5df:ffff:ffff:ffff:ffff:ffff:ffff
9529a0:5e0::/2829a0:5ef:ffff:ffff:ffff:ffff:ffff:ffff
9629a0:5f0::/2829a0:5ff:ffff:ffff:ffff:ffff:ffff:ffff
9729a0:600::/2829a0:60f:ffff:ffff:ffff:ffff:ffff:ffff
9829a0:610::/2829a0:61f:ffff:ffff:ffff:ffff:ffff:ffff
9929a0:620::/2829a0:62f:ffff:ffff:ffff:ffff:ffff:ffff
10029a0:630::/2829a0:63f:ffff:ffff:ffff:ffff:ffff:ffff
10129a0:640::/2829a0:64f:ffff:ffff:ffff:ffff:ffff:ffff
10229a0:650::/2829a0:65f:ffff:ffff:ffff:ffff:ffff:ffff
10329a0:660::/2829a0:66f:ffff:ffff:ffff:ffff:ffff:ffff
10429a0:670::/2829a0:67f:ffff:ffff:ffff:ffff:ffff:ffff
10529a0:680::/2829a0:68f:ffff:ffff:ffff:ffff:ffff:ffff
10629a0:690::/2829a0:69f:ffff:ffff:ffff:ffff:ffff:ffff
10729a0:6a0::/2829a0:6af:ffff:ffff:ffff:ffff:ffff:ffff
10829a0:6b0::/2829a0:6bf:ffff:ffff:ffff:ffff:ffff:ffff
10929a0:6c0::/2829a0:6cf:ffff:ffff:ffff:ffff:ffff:ffff
11029a0:6d0::/2829a0:6df:ffff:ffff:ffff:ffff:ffff:ffff
11129a0:6e0::/2829a0:6ef:ffff:ffff:ffff:ffff:ffff:ffff
11229a0:6f0::/2829a0:6ff:ffff:ffff:ffff:ffff:ffff:ffff
11329a0:700::/2829a0:70f:ffff:ffff:ffff:ffff:ffff:ffff
11429a0:710::/2829a0:71f:ffff:ffff:ffff:ffff:ffff:ffff
11529a0:720::/2829a0:72f:ffff:ffff:ffff:ffff:ffff:ffff
11629a0:730::/2829a0:73f:ffff:ffff:ffff:ffff:ffff:ffff
11729a0:740::/2829a0:74f:ffff:ffff:ffff:ffff:ffff:ffff
11829a0:750::/2829a0:75f:ffff:ffff:ffff:ffff:ffff:ffff
11929a0:760::/2829a0:76f:ffff:ffff:ffff:ffff:ffff:ffff
12029a0:770::/2829a0:77f:ffff:ffff:ffff:ffff:ffff:ffff
12129a0:780::/2829a0:78f:ffff:ffff:ffff:ffff:ffff:ffff
12229a0:790::/2829a0:79f:ffff:ffff:ffff:ffff:ffff:ffff
12329a0:7a0::/2829a0:7af:ffff:ffff:ffff:ffff:ffff:ffff
12429a0:7b0::/2829a0:7bf:ffff:ffff:ffff:ffff:ffff:ffff
12529a0:7c0::/2829a0:7cf:ffff:ffff:ffff:ffff:ffff:ffff
12629a0:7d0::/2829a0:7df:ffff:ffff:ffff:ffff:ffff:ffff
12729a0:7e0::/2829a0:7ef:ffff:ffff:ffff:ffff:ffff:ffff
12829a0:7f0::/2829a0:7ff:ffff:ffff:ffff:ffff:ffff:ffff
12929a0:800::/2829a0:80f:ffff:ffff:ffff:ffff:ffff:ffff
13029a0:810::/2829a0:81f:ffff:ffff:ffff:ffff:ffff:ffff
13129a0:820::/2829a0:82f:ffff:ffff:ffff:ffff:ffff:ffff
13229a0:830::/2829a0:83f:ffff:ffff:ffff:ffff:ffff:ffff
13329a0:840::/2829a0:84f:ffff:ffff:ffff:ffff:ffff:ffff
13429a0:850::/2829a0:85f:ffff:ffff:ffff:ffff:ffff:ffff
13529a0:860::/2829a0:86f:ffff:ffff:ffff:ffff:ffff:ffff
13629a0:870::/2829a0:87f:ffff:ffff:ffff:ffff:ffff:ffff
13729a0:880::/2829a0:88f:ffff:ffff:ffff:ffff:ffff:ffff
13829a0:890::/2829a0:89f:ffff:ffff:ffff:ffff:ffff:ffff
13929a0:8a0::/2829a0:8af:ffff:ffff:ffff:ffff:ffff:ffff
14029a0:8b0::/2829a0:8bf:ffff:ffff:ffff:ffff:ffff:ffff
14129a0:8c0::/2829a0:8cf:ffff:ffff:ffff:ffff:ffff:ffff
14229a0:8d0::/2829a0:8df:ffff:ffff:ffff:ffff:ffff:ffff
14329a0:8e0::/2829a0:8ef:ffff:ffff:ffff:ffff:ffff:ffff
14429a0:8f0::/2829a0:8ff:ffff:ffff:ffff:ffff:ffff:ffff
14529a0:900::/2829a0:90f:ffff:ffff:ffff:ffff:ffff:ffff
14629a0:910::/2829a0:91f:ffff:ffff:ffff:ffff:ffff:ffff
14729a0:920::/2829a0:92f:ffff:ffff:ffff:ffff:ffff:ffff
14829a0:930::/2829a0:93f:ffff:ffff:ffff:ffff:ffff:ffff
14929a0:940::/2829a0:94f:ffff:ffff:ffff:ffff:ffff:ffff
15029a0:950::/2829a0:95f:ffff:ffff:ffff:ffff:ffff:ffff
15129a0:960::/2829a0:96f:ffff:ffff:ffff:ffff:ffff:ffff
15229a0:970::/2829a0:97f:ffff:ffff:ffff:ffff:ffff:ffff
15329a0:980::/2829a0:98f:ffff:ffff:ffff:ffff:ffff:ffff
15429a0:990::/2829a0:99f:ffff:ffff:ffff:ffff:ffff:ffff
15529a0:9a0::/2829a0:9af:ffff:ffff:ffff:ffff:ffff:ffff
15629a0:9b0::/2829a0:9bf:ffff:ffff:ffff:ffff:ffff:ffff
15729a0:9c0::/2829a0:9cf:ffff:ffff:ffff:ffff:ffff:ffff
15829a0:9d0::/2829a0:9df:ffff:ffff:ffff:ffff:ffff:ffff
15929a0:9e0::/2829a0:9ef:ffff:ffff:ffff:ffff:ffff:ffff
16029a0:9f0::/2829a0:9ff:ffff:ffff:ffff:ffff:ffff:ffff
16129a0:a00::/2829a0:a0f:ffff:ffff:ffff:ffff:ffff:ffff
16229a0:a10::/2829a0:a1f:ffff:ffff:ffff:ffff:ffff:ffff
16329a0:a20::/2829a0:a2f:ffff:ffff:ffff:ffff:ffff:ffff
16429a0:a30::/2829a0:a3f:ffff:ffff:ffff:ffff:ffff:ffff
16529a0:a40::/2829a0:a4f:ffff:ffff:ffff:ffff:ffff:ffff
16629a0:a50::/2829a0:a5f:ffff:ffff:ffff:ffff:ffff:ffff
16729a0:a60::/2829a0:a6f:ffff:ffff:ffff:ffff:ffff:ffff
16829a0:a70::/2829a0:a7f:ffff:ffff:ffff:ffff:ffff:ffff
16929a0:a80::/2829a0:a8f:ffff:ffff:ffff:ffff:ffff:ffff
17029a0:a90::/2829a0:a9f:ffff:ffff:ffff:ffff:ffff:ffff
17129a0:aa0::/2829a0:aaf:ffff:ffff:ffff:ffff:ffff:ffff
17229a0:ab0::/2829a0:abf:ffff:ffff:ffff:ffff:ffff:ffff
17329a0:ac0::/2829a0:acf:ffff:ffff:ffff:ffff:ffff:ffff
17429a0:ad0::/2829a0:adf:ffff:ffff:ffff:ffff:ffff:ffff
17529a0:ae0::/2829a0:aef:ffff:ffff:ffff:ffff:ffff:ffff
17629a0:af0::/2829a0:aff:ffff:ffff:ffff:ffff:ffff:ffff
17729a0:b00::/2829a0:b0f:ffff:ffff:ffff:ffff:ffff:ffff
17829a0:b10::/2829a0:b1f:ffff:ffff:ffff:ffff:ffff:ffff
17929a0:b20::/2829a0:b2f:ffff:ffff:ffff:ffff:ffff:ffff
18029a0:b30::/2829a0:b3f:ffff:ffff:ffff:ffff:ffff:ffff
18129a0:b40::/2829a0:b4f:ffff:ffff:ffff:ffff:ffff:ffff
18229a0:b50::/2829a0:b5f:ffff:ffff:ffff:ffff:ffff:ffff
18329a0:b60::/2829a0:b6f:ffff:ffff:ffff:ffff:ffff:ffff
18429a0:b70::/2829a0:b7f:ffff:ffff:ffff:ffff:ffff:ffff
18529a0:b80::/2829a0:b8f:ffff:ffff:ffff:ffff:ffff:ffff
18629a0:b90::/2829a0:b9f:ffff:ffff:ffff:ffff:ffff:ffff
18729a0:ba0::/2829a0:baf:ffff:ffff:ffff:ffff:ffff:ffff
18829a0:bb0::/2829a0:bbf:ffff:ffff:ffff:ffff:ffff:ffff
18929a0:bc0::/2829a0:bcf:ffff:ffff:ffff:ffff:ffff:ffff
19029a0:bd0::/2829a0:bdf:ffff:ffff:ffff:ffff:ffff:ffff
19129a0:be0::/2829a0:bef:ffff:ffff:ffff:ffff:ffff:ffff
19229a0:bf0::/2829a0:bff:ffff:ffff:ffff:ffff:ffff:ffff
19329a0:c00::/2829a0:c0f:ffff:ffff:ffff:ffff:ffff:ffff
19429a0:c10::/2829a0:c1f:ffff:ffff:ffff:ffff:ffff:ffff
19529a0:c20::/2829a0:c2f:ffff:ffff:ffff:ffff:ffff:ffff
19629a0:c30::/2829a0:c3f:ffff:ffff:ffff:ffff:ffff:ffff
19729a0:c40::/2829a0:c4f:ffff:ffff:ffff:ffff:ffff:ffff
19829a0:c50::/2829a0:c5f:ffff:ffff:ffff:ffff:ffff:ffff
19929a0:c60::/2829a0:c6f:ffff:ffff:ffff:ffff:ffff:ffff
20029a0:c70::/2829a0:c7f:ffff:ffff:ffff:ffff:ffff:ffff
20129a0:c80::/2829a0:c8f:ffff:ffff:ffff:ffff:ffff:ffff
20229a0:c90::/2829a0:c9f:ffff:ffff:ffff:ffff:ffff:ffff
20329a0:ca0::/2829a0:caf:ffff:ffff:ffff:ffff:ffff:ffff
20429a0:cb0::/2829a0:cbf:ffff:ffff:ffff:ffff:ffff:ffff
20529a0:cc0::/2829a0:ccf:ffff:ffff:ffff:ffff:ffff:ffff
20629a0:cd0::/2829a0:cdf:ffff:ffff:ffff:ffff:ffff:ffff
20729a0:ce0::/2829a0:cef:ffff:ffff:ffff:ffff:ffff:ffff
20829a0:cf0::/2829a0:cff:ffff:ffff:ffff:ffff:ffff:ffff
20929a0:d00::/2829a0:d0f:ffff:ffff:ffff:ffff:ffff:ffff
21029a0:d10::/2829a0:d1f:ffff:ffff:ffff:ffff:ffff:ffff
21129a0:d20::/2829a0:d2f:ffff:ffff:ffff:ffff:ffff:ffff
21229a0:d30::/2829a0:d3f:ffff:ffff:ffff:ffff:ffff:ffff
21329a0:d40::/2829a0:d4f:ffff:ffff:ffff:ffff:ffff:ffff
21429a0:d50::/2829a0:d5f:ffff:ffff:ffff:ffff:ffff:ffff
21529a0:d60::/2829a0:d6f:ffff:ffff:ffff:ffff:ffff:ffff
21629a0:d70::/2829a0:d7f:ffff:ffff:ffff:ffff:ffff:ffff
21729a0:d80::/2829a0:d8f:ffff:ffff:ffff:ffff:ffff:ffff
21829a0:d90::/2829a0:d9f:ffff:ffff:ffff:ffff:ffff:ffff
21929a0:da0::/2829a0:daf:ffff:ffff:ffff:ffff:ffff:ffff
22029a0:db0::/2829a0:dbf:ffff:ffff:ffff:ffff:ffff:ffff
22129a0:dc0::/2829a0:dcf:ffff:ffff:ffff:ffff:ffff:ffff
22229a0:dd0::/2829a0:ddf:ffff:ffff:ffff:ffff:ffff:ffff
22329a0:de0::/2829a0:def:ffff:ffff:ffff:ffff:ffff:ffff
22429a0:df0::/2829a0:dff:ffff:ffff:ffff:ffff:ffff:ffff
22529a0:e00::/2829a0:e0f:ffff:ffff:ffff:ffff:ffff:ffff
22629a0:e10::/2829a0:e1f:ffff:ffff:ffff:ffff:ffff:ffff
22729a0:e20::/2829a0:e2f:ffff:ffff:ffff:ffff:ffff:ffff
22829a0:e30::/2829a0:e3f:ffff:ffff:ffff:ffff:ffff:ffff
22929a0:e40::/2829a0:e4f:ffff:ffff:ffff:ffff:ffff:ffff
23029a0:e50::/2829a0:e5f:ffff:ffff:ffff:ffff:ffff:ffff
23129a0:e60::/2829a0:e6f:ffff:ffff:ffff:ffff:ffff:ffff
23229a0:e70::/2829a0:e7f:ffff:ffff:ffff:ffff:ffff:ffff
23329a0:e80::/2829a0:e8f:ffff:ffff:ffff:ffff:ffff:ffff
23429a0:e90::/2829a0:e9f:ffff:ffff:ffff:ffff:ffff:ffff
23529a0:ea0::/2829a0:eaf:ffff:ffff:ffff:ffff:ffff:ffff
23629a0:eb0::/2829a0:ebf:ffff:ffff:ffff:ffff:ffff:ffff
23729a0:ec0::/2829a0:ecf:ffff:ffff:ffff:ffff:ffff:ffff
23829a0:ed0::/2829a0:edf:ffff:ffff:ffff:ffff:ffff:ffff
23929a0:ee0::/2829a0:eef:ffff:ffff:ffff:ffff:ffff:ffff
24029a0:ef0::/2829a0:eff:ffff:ffff:ffff:ffff:ffff:ffff
24129a0:f00::/2829a0:f0f:ffff:ffff:ffff:ffff:ffff:ffff
24229a0:f10::/2829a0:f1f:ffff:ffff:ffff:ffff:ffff:ffff
24329a0:f20::/2829a0:f2f:ffff:ffff:ffff:ffff:ffff:ffff
24429a0:f30::/2829a0:f3f:ffff:ffff:ffff:ffff:ffff:ffff
24529a0:f40::/2829a0:f4f:ffff:ffff:ffff:ffff:ffff:ffff
24629a0:f50::/2829a0:f5f:ffff:ffff:ffff:ffff:ffff:ffff
24729a0:f60::/2829a0:f6f:ffff:ffff:ffff:ffff:ffff:ffff
24829a0:f70::/2829a0:f7f:ffff:ffff:ffff:ffff:ffff:ffff
24929a0:f80::/2829a0:f8f:ffff:ffff:ffff:ffff:ffff:ffff
25029a0:f90::/2829a0:f9f:ffff:ffff:ffff:ffff:ffff:ffff
25129a0:fa0::/2829a0:faf:ffff:ffff:ffff:ffff:ffff:ffff
25229a0:fb0::/2829a0:fbf:ffff:ffff:ffff:ffff:ffff:ffff
25329a0:fc0::/2829a0:fcf:ffff:ffff:ffff:ffff:ffff:ffff
25429a0:fd0::/2829a0:fdf:ffff:ffff:ffff:ffff:ffff:ffff
25529a0:fe0::/2829a0:fef:ffff:ffff:ffff:ffff:ffff:ffff
25629a0:ff0::/2829a0: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.