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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
32af::/16
First address
32af::
Last address
32af: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
32af:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.a.2.3.ip6.arpa
Split into smaller subnets/32
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

32af::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
132af::/3232af:0:ffff:ffff:ffff:ffff:ffff:ffff
232af:1::/3232af:1:ffff:ffff:ffff:ffff:ffff:ffff
332af:2::/3232af:2:ffff:ffff:ffff:ffff:ffff:ffff
432af:3::/3232af:3:ffff:ffff:ffff:ffff:ffff:ffff
532af:4::/3232af:4:ffff:ffff:ffff:ffff:ffff:ffff
632af:5::/3232af:5:ffff:ffff:ffff:ffff:ffff:ffff
732af:6::/3232af:6:ffff:ffff:ffff:ffff:ffff:ffff
832af:7::/3232af:7:ffff:ffff:ffff:ffff:ffff:ffff
932af:8::/3232af:8:ffff:ffff:ffff:ffff:ffff:ffff
1032af:9::/3232af:9:ffff:ffff:ffff:ffff:ffff:ffff
1132af:a::/3232af:a:ffff:ffff:ffff:ffff:ffff:ffff
1232af:b::/3232af:b:ffff:ffff:ffff:ffff:ffff:ffff
1332af:c::/3232af:c:ffff:ffff:ffff:ffff:ffff:ffff
1432af:d::/3232af:d:ffff:ffff:ffff:ffff:ffff:ffff
1532af:e::/3232af:e:ffff:ffff:ffff:ffff:ffff:ffff
1632af:f::/3232af:f:ffff:ffff:ffff:ffff:ffff:ffff
1732af:10::/3232af:10:ffff:ffff:ffff:ffff:ffff:ffff
1832af:11::/3232af:11:ffff:ffff:ffff:ffff:ffff:ffff
1932af:12::/3232af:12:ffff:ffff:ffff:ffff:ffff:ffff
2032af:13::/3232af:13:ffff:ffff:ffff:ffff:ffff:ffff
2132af:14::/3232af:14:ffff:ffff:ffff:ffff:ffff:ffff
2232af:15::/3232af:15:ffff:ffff:ffff:ffff:ffff:ffff
2332af:16::/3232af:16:ffff:ffff:ffff:ffff:ffff:ffff
2432af:17::/3232af:17:ffff:ffff:ffff:ffff:ffff:ffff
2532af:18::/3232af:18:ffff:ffff:ffff:ffff:ffff:ffff
2632af:19::/3232af:19:ffff:ffff:ffff:ffff:ffff:ffff
2732af:1a::/3232af:1a:ffff:ffff:ffff:ffff:ffff:ffff
2832af:1b::/3232af:1b:ffff:ffff:ffff:ffff:ffff:ffff
2932af:1c::/3232af:1c:ffff:ffff:ffff:ffff:ffff:ffff
3032af:1d::/3232af:1d:ffff:ffff:ffff:ffff:ffff:ffff
3132af:1e::/3232af:1e:ffff:ffff:ffff:ffff:ffff:ffff
3232af:1f::/3232af:1f:ffff:ffff:ffff:ffff:ffff:ffff
3332af:20::/3232af:20:ffff:ffff:ffff:ffff:ffff:ffff
3432af:21::/3232af:21:ffff:ffff:ffff:ffff:ffff:ffff
3532af:22::/3232af:22:ffff:ffff:ffff:ffff:ffff:ffff
3632af:23::/3232af:23:ffff:ffff:ffff:ffff:ffff:ffff
3732af:24::/3232af:24:ffff:ffff:ffff:ffff:ffff:ffff
3832af:25::/3232af:25:ffff:ffff:ffff:ffff:ffff:ffff
3932af:26::/3232af:26:ffff:ffff:ffff:ffff:ffff:ffff
4032af:27::/3232af:27:ffff:ffff:ffff:ffff:ffff:ffff
4132af:28::/3232af:28:ffff:ffff:ffff:ffff:ffff:ffff
4232af:29::/3232af:29:ffff:ffff:ffff:ffff:ffff:ffff
4332af:2a::/3232af:2a:ffff:ffff:ffff:ffff:ffff:ffff
4432af:2b::/3232af:2b:ffff:ffff:ffff:ffff:ffff:ffff
4532af:2c::/3232af:2c:ffff:ffff:ffff:ffff:ffff:ffff
4632af:2d::/3232af:2d:ffff:ffff:ffff:ffff:ffff:ffff
4732af:2e::/3232af:2e:ffff:ffff:ffff:ffff:ffff:ffff
4832af:2f::/3232af:2f:ffff:ffff:ffff:ffff:ffff:ffff
4932af:30::/3232af:30:ffff:ffff:ffff:ffff:ffff:ffff
5032af:31::/3232af:31:ffff:ffff:ffff:ffff:ffff:ffff
5132af:32::/3232af:32:ffff:ffff:ffff:ffff:ffff:ffff
5232af:33::/3232af:33:ffff:ffff:ffff:ffff:ffff:ffff
5332af:34::/3232af:34:ffff:ffff:ffff:ffff:ffff:ffff
5432af:35::/3232af:35:ffff:ffff:ffff:ffff:ffff:ffff
5532af:36::/3232af:36:ffff:ffff:ffff:ffff:ffff:ffff
5632af:37::/3232af:37:ffff:ffff:ffff:ffff:ffff:ffff
5732af:38::/3232af:38:ffff:ffff:ffff:ffff:ffff:ffff
5832af:39::/3232af:39:ffff:ffff:ffff:ffff:ffff:ffff
5932af:3a::/3232af:3a:ffff:ffff:ffff:ffff:ffff:ffff
6032af:3b::/3232af:3b:ffff:ffff:ffff:ffff:ffff:ffff
6132af:3c::/3232af:3c:ffff:ffff:ffff:ffff:ffff:ffff
6232af:3d::/3232af:3d:ffff:ffff:ffff:ffff:ffff:ffff
6332af:3e::/3232af:3e:ffff:ffff:ffff:ffff:ffff:ffff
6432af:3f::/3232af:3f:ffff:ffff:ffff:ffff:ffff:ffff
6532af:40::/3232af:40:ffff:ffff:ffff:ffff:ffff:ffff
6632af:41::/3232af:41:ffff:ffff:ffff:ffff:ffff:ffff
6732af:42::/3232af:42:ffff:ffff:ffff:ffff:ffff:ffff
6832af:43::/3232af:43:ffff:ffff:ffff:ffff:ffff:ffff
6932af:44::/3232af:44:ffff:ffff:ffff:ffff:ffff:ffff
7032af:45::/3232af:45:ffff:ffff:ffff:ffff:ffff:ffff
7132af:46::/3232af:46:ffff:ffff:ffff:ffff:ffff:ffff
7232af:47::/3232af:47:ffff:ffff:ffff:ffff:ffff:ffff
7332af:48::/3232af:48:ffff:ffff:ffff:ffff:ffff:ffff
7432af:49::/3232af:49:ffff:ffff:ffff:ffff:ffff:ffff
7532af:4a::/3232af:4a:ffff:ffff:ffff:ffff:ffff:ffff
7632af:4b::/3232af:4b:ffff:ffff:ffff:ffff:ffff:ffff
7732af:4c::/3232af:4c:ffff:ffff:ffff:ffff:ffff:ffff
7832af:4d::/3232af:4d:ffff:ffff:ffff:ffff:ffff:ffff
7932af:4e::/3232af:4e:ffff:ffff:ffff:ffff:ffff:ffff
8032af:4f::/3232af:4f:ffff:ffff:ffff:ffff:ffff:ffff
8132af:50::/3232af:50:ffff:ffff:ffff:ffff:ffff:ffff
8232af:51::/3232af:51:ffff:ffff:ffff:ffff:ffff:ffff
8332af:52::/3232af:52:ffff:ffff:ffff:ffff:ffff:ffff
8432af:53::/3232af:53:ffff:ffff:ffff:ffff:ffff:ffff
8532af:54::/3232af:54:ffff:ffff:ffff:ffff:ffff:ffff
8632af:55::/3232af:55:ffff:ffff:ffff:ffff:ffff:ffff
8732af:56::/3232af:56:ffff:ffff:ffff:ffff:ffff:ffff
8832af:57::/3232af:57:ffff:ffff:ffff:ffff:ffff:ffff
8932af:58::/3232af:58:ffff:ffff:ffff:ffff:ffff:ffff
9032af:59::/3232af:59:ffff:ffff:ffff:ffff:ffff:ffff
9132af:5a::/3232af:5a:ffff:ffff:ffff:ffff:ffff:ffff
9232af:5b::/3232af:5b:ffff:ffff:ffff:ffff:ffff:ffff
9332af:5c::/3232af:5c:ffff:ffff:ffff:ffff:ffff:ffff
9432af:5d::/3232af:5d:ffff:ffff:ffff:ffff:ffff:ffff
9532af:5e::/3232af:5e:ffff:ffff:ffff:ffff:ffff:ffff
9632af:5f::/3232af:5f:ffff:ffff:ffff:ffff:ffff:ffff
9732af:60::/3232af:60:ffff:ffff:ffff:ffff:ffff:ffff
9832af:61::/3232af:61:ffff:ffff:ffff:ffff:ffff:ffff
9932af:62::/3232af:62:ffff:ffff:ffff:ffff:ffff:ffff
10032af:63::/3232af:63:ffff:ffff:ffff:ffff:ffff:ffff
10132af:64::/3232af:64:ffff:ffff:ffff:ffff:ffff:ffff
10232af:65::/3232af:65:ffff:ffff:ffff:ffff:ffff:ffff
10332af:66::/3232af:66:ffff:ffff:ffff:ffff:ffff:ffff
10432af:67::/3232af:67:ffff:ffff:ffff:ffff:ffff:ffff
10532af:68::/3232af:68:ffff:ffff:ffff:ffff:ffff:ffff
10632af:69::/3232af:69:ffff:ffff:ffff:ffff:ffff:ffff
10732af:6a::/3232af:6a:ffff:ffff:ffff:ffff:ffff:ffff
10832af:6b::/3232af:6b:ffff:ffff:ffff:ffff:ffff:ffff
10932af:6c::/3232af:6c:ffff:ffff:ffff:ffff:ffff:ffff
11032af:6d::/3232af:6d:ffff:ffff:ffff:ffff:ffff:ffff
11132af:6e::/3232af:6e:ffff:ffff:ffff:ffff:ffff:ffff
11232af:6f::/3232af:6f:ffff:ffff:ffff:ffff:ffff:ffff
11332af:70::/3232af:70:ffff:ffff:ffff:ffff:ffff:ffff
11432af:71::/3232af:71:ffff:ffff:ffff:ffff:ffff:ffff
11532af:72::/3232af:72:ffff:ffff:ffff:ffff:ffff:ffff
11632af:73::/3232af:73:ffff:ffff:ffff:ffff:ffff:ffff
11732af:74::/3232af:74:ffff:ffff:ffff:ffff:ffff:ffff
11832af:75::/3232af:75:ffff:ffff:ffff:ffff:ffff:ffff
11932af:76::/3232af:76:ffff:ffff:ffff:ffff:ffff:ffff
12032af:77::/3232af:77:ffff:ffff:ffff:ffff:ffff:ffff
12132af:78::/3232af:78:ffff:ffff:ffff:ffff:ffff:ffff
12232af:79::/3232af:79:ffff:ffff:ffff:ffff:ffff:ffff
12332af:7a::/3232af:7a:ffff:ffff:ffff:ffff:ffff:ffff
12432af:7b::/3232af:7b:ffff:ffff:ffff:ffff:ffff:ffff
12532af:7c::/3232af:7c:ffff:ffff:ffff:ffff:ffff:ffff
12632af:7d::/3232af:7d:ffff:ffff:ffff:ffff:ffff:ffff
12732af:7e::/3232af:7e:ffff:ffff:ffff:ffff:ffff:ffff
12832af:7f::/3232af:7f:ffff:ffff:ffff:ffff:ffff:ffff
12932af:80::/3232af:80:ffff:ffff:ffff:ffff:ffff:ffff
13032af:81::/3232af:81:ffff:ffff:ffff:ffff:ffff:ffff
13132af:82::/3232af:82:ffff:ffff:ffff:ffff:ffff:ffff
13232af:83::/3232af:83:ffff:ffff:ffff:ffff:ffff:ffff
13332af:84::/3232af:84:ffff:ffff:ffff:ffff:ffff:ffff
13432af:85::/3232af:85:ffff:ffff:ffff:ffff:ffff:ffff
13532af:86::/3232af:86:ffff:ffff:ffff:ffff:ffff:ffff
13632af:87::/3232af:87:ffff:ffff:ffff:ffff:ffff:ffff
13732af:88::/3232af:88:ffff:ffff:ffff:ffff:ffff:ffff
13832af:89::/3232af:89:ffff:ffff:ffff:ffff:ffff:ffff
13932af:8a::/3232af:8a:ffff:ffff:ffff:ffff:ffff:ffff
14032af:8b::/3232af:8b:ffff:ffff:ffff:ffff:ffff:ffff
14132af:8c::/3232af:8c:ffff:ffff:ffff:ffff:ffff:ffff
14232af:8d::/3232af:8d:ffff:ffff:ffff:ffff:ffff:ffff
14332af:8e::/3232af:8e:ffff:ffff:ffff:ffff:ffff:ffff
14432af:8f::/3232af:8f:ffff:ffff:ffff:ffff:ffff:ffff
14532af:90::/3232af:90:ffff:ffff:ffff:ffff:ffff:ffff
14632af:91::/3232af:91:ffff:ffff:ffff:ffff:ffff:ffff
14732af:92::/3232af:92:ffff:ffff:ffff:ffff:ffff:ffff
14832af:93::/3232af:93:ffff:ffff:ffff:ffff:ffff:ffff
14932af:94::/3232af:94:ffff:ffff:ffff:ffff:ffff:ffff
15032af:95::/3232af:95:ffff:ffff:ffff:ffff:ffff:ffff
15132af:96::/3232af:96:ffff:ffff:ffff:ffff:ffff:ffff
15232af:97::/3232af:97:ffff:ffff:ffff:ffff:ffff:ffff
15332af:98::/3232af:98:ffff:ffff:ffff:ffff:ffff:ffff
15432af:99::/3232af:99:ffff:ffff:ffff:ffff:ffff:ffff
15532af:9a::/3232af:9a:ffff:ffff:ffff:ffff:ffff:ffff
15632af:9b::/3232af:9b:ffff:ffff:ffff:ffff:ffff:ffff
15732af:9c::/3232af:9c:ffff:ffff:ffff:ffff:ffff:ffff
15832af:9d::/3232af:9d:ffff:ffff:ffff:ffff:ffff:ffff
15932af:9e::/3232af:9e:ffff:ffff:ffff:ffff:ffff:ffff
16032af:9f::/3232af:9f:ffff:ffff:ffff:ffff:ffff:ffff
16132af:a0::/3232af:a0:ffff:ffff:ffff:ffff:ffff:ffff
16232af:a1::/3232af:a1:ffff:ffff:ffff:ffff:ffff:ffff
16332af:a2::/3232af:a2:ffff:ffff:ffff:ffff:ffff:ffff
16432af:a3::/3232af:a3:ffff:ffff:ffff:ffff:ffff:ffff
16532af:a4::/3232af:a4:ffff:ffff:ffff:ffff:ffff:ffff
16632af:a5::/3232af:a5:ffff:ffff:ffff:ffff:ffff:ffff
16732af:a6::/3232af:a6:ffff:ffff:ffff:ffff:ffff:ffff
16832af:a7::/3232af:a7:ffff:ffff:ffff:ffff:ffff:ffff
16932af:a8::/3232af:a8:ffff:ffff:ffff:ffff:ffff:ffff
17032af:a9::/3232af:a9:ffff:ffff:ffff:ffff:ffff:ffff
17132af:aa::/3232af:aa:ffff:ffff:ffff:ffff:ffff:ffff
17232af:ab::/3232af:ab:ffff:ffff:ffff:ffff:ffff:ffff
17332af:ac::/3232af:ac:ffff:ffff:ffff:ffff:ffff:ffff
17432af:ad::/3232af:ad:ffff:ffff:ffff:ffff:ffff:ffff
17532af:ae::/3232af:ae:ffff:ffff:ffff:ffff:ffff:ffff
17632af:af::/3232af:af:ffff:ffff:ffff:ffff:ffff:ffff
17732af:b0::/3232af:b0:ffff:ffff:ffff:ffff:ffff:ffff
17832af:b1::/3232af:b1:ffff:ffff:ffff:ffff:ffff:ffff
17932af:b2::/3232af:b2:ffff:ffff:ffff:ffff:ffff:ffff
18032af:b3::/3232af:b3:ffff:ffff:ffff:ffff:ffff:ffff
18132af:b4::/3232af:b4:ffff:ffff:ffff:ffff:ffff:ffff
18232af:b5::/3232af:b5:ffff:ffff:ffff:ffff:ffff:ffff
18332af:b6::/3232af:b6:ffff:ffff:ffff:ffff:ffff:ffff
18432af:b7::/3232af:b7:ffff:ffff:ffff:ffff:ffff:ffff
18532af:b8::/3232af:b8:ffff:ffff:ffff:ffff:ffff:ffff
18632af:b9::/3232af:b9:ffff:ffff:ffff:ffff:ffff:ffff
18732af:ba::/3232af:ba:ffff:ffff:ffff:ffff:ffff:ffff
18832af:bb::/3232af:bb:ffff:ffff:ffff:ffff:ffff:ffff
18932af:bc::/3232af:bc:ffff:ffff:ffff:ffff:ffff:ffff
19032af:bd::/3232af:bd:ffff:ffff:ffff:ffff:ffff:ffff
19132af:be::/3232af:be:ffff:ffff:ffff:ffff:ffff:ffff
19232af:bf::/3232af:bf:ffff:ffff:ffff:ffff:ffff:ffff
19332af:c0::/3232af:c0:ffff:ffff:ffff:ffff:ffff:ffff
19432af:c1::/3232af:c1:ffff:ffff:ffff:ffff:ffff:ffff
19532af:c2::/3232af:c2:ffff:ffff:ffff:ffff:ffff:ffff
19632af:c3::/3232af:c3:ffff:ffff:ffff:ffff:ffff:ffff
19732af:c4::/3232af:c4:ffff:ffff:ffff:ffff:ffff:ffff
19832af:c5::/3232af:c5:ffff:ffff:ffff:ffff:ffff:ffff
19932af:c6::/3232af:c6:ffff:ffff:ffff:ffff:ffff:ffff
20032af:c7::/3232af:c7:ffff:ffff:ffff:ffff:ffff:ffff
20132af:c8::/3232af:c8:ffff:ffff:ffff:ffff:ffff:ffff
20232af:c9::/3232af:c9:ffff:ffff:ffff:ffff:ffff:ffff
20332af:ca::/3232af:ca:ffff:ffff:ffff:ffff:ffff:ffff
20432af:cb::/3232af:cb:ffff:ffff:ffff:ffff:ffff:ffff
20532af:cc::/3232af:cc:ffff:ffff:ffff:ffff:ffff:ffff
20632af:cd::/3232af:cd:ffff:ffff:ffff:ffff:ffff:ffff
20732af:ce::/3232af:ce:ffff:ffff:ffff:ffff:ffff:ffff
20832af:cf::/3232af:cf:ffff:ffff:ffff:ffff:ffff:ffff
20932af:d0::/3232af:d0:ffff:ffff:ffff:ffff:ffff:ffff
21032af:d1::/3232af:d1:ffff:ffff:ffff:ffff:ffff:ffff
21132af:d2::/3232af:d2:ffff:ffff:ffff:ffff:ffff:ffff
21232af:d3::/3232af:d3:ffff:ffff:ffff:ffff:ffff:ffff
21332af:d4::/3232af:d4:ffff:ffff:ffff:ffff:ffff:ffff
21432af:d5::/3232af:d5:ffff:ffff:ffff:ffff:ffff:ffff
21532af:d6::/3232af:d6:ffff:ffff:ffff:ffff:ffff:ffff
21632af:d7::/3232af:d7:ffff:ffff:ffff:ffff:ffff:ffff
21732af:d8::/3232af:d8:ffff:ffff:ffff:ffff:ffff:ffff
21832af:d9::/3232af:d9:ffff:ffff:ffff:ffff:ffff:ffff
21932af:da::/3232af:da:ffff:ffff:ffff:ffff:ffff:ffff
22032af:db::/3232af:db:ffff:ffff:ffff:ffff:ffff:ffff
22132af:dc::/3232af:dc:ffff:ffff:ffff:ffff:ffff:ffff
22232af:dd::/3232af:dd:ffff:ffff:ffff:ffff:ffff:ffff
22332af:de::/3232af:de:ffff:ffff:ffff:ffff:ffff:ffff
22432af:df::/3232af:df:ffff:ffff:ffff:ffff:ffff:ffff
22532af:e0::/3232af:e0:ffff:ffff:ffff:ffff:ffff:ffff
22632af:e1::/3232af:e1:ffff:ffff:ffff:ffff:ffff:ffff
22732af:e2::/3232af:e2:ffff:ffff:ffff:ffff:ffff:ffff
22832af:e3::/3232af:e3:ffff:ffff:ffff:ffff:ffff:ffff
22932af:e4::/3232af:e4:ffff:ffff:ffff:ffff:ffff:ffff
23032af:e5::/3232af:e5:ffff:ffff:ffff:ffff:ffff:ffff
23132af:e6::/3232af:e6:ffff:ffff:ffff:ffff:ffff:ffff
23232af:e7::/3232af:e7:ffff:ffff:ffff:ffff:ffff:ffff
23332af:e8::/3232af:e8:ffff:ffff:ffff:ffff:ffff:ffff
23432af:e9::/3232af:e9:ffff:ffff:ffff:ffff:ffff:ffff
23532af:ea::/3232af:ea:ffff:ffff:ffff:ffff:ffff:ffff
23632af:eb::/3232af:eb:ffff:ffff:ffff:ffff:ffff:ffff
23732af:ec::/3232af:ec:ffff:ffff:ffff:ffff:ffff:ffff
23832af:ed::/3232af:ed:ffff:ffff:ffff:ffff:ffff:ffff
23932af:ee::/3232af:ee:ffff:ffff:ffff:ffff:ffff:ffff
24032af:ef::/3232af:ef:ffff:ffff:ffff:ffff:ffff:ffff
24132af:f0::/3232af:f0:ffff:ffff:ffff:ffff:ffff:ffff
24232af:f1::/3232af:f1:ffff:ffff:ffff:ffff:ffff:ffff
24332af:f2::/3232af:f2:ffff:ffff:ffff:ffff:ffff:ffff
24432af:f3::/3232af:f3:ffff:ffff:ffff:ffff:ffff:ffff
24532af:f4::/3232af:f4:ffff:ffff:ffff:ffff:ffff:ffff
24632af:f5::/3232af:f5:ffff:ffff:ffff:ffff:ffff:ffff
24732af:f6::/3232af:f6:ffff:ffff:ffff:ffff:ffff:ffff
24832af:f7::/3232af:f7:ffff:ffff:ffff:ffff:ffff:ffff
24932af:f8::/3232af:f8:ffff:ffff:ffff:ffff:ffff:ffff
25032af:f9::/3232af:f9:ffff:ffff:ffff:ffff:ffff:ffff
25132af:fa::/3232af:fa:ffff:ffff:ffff:ffff:ffff:ffff
25232af:fb::/3232af:fb:ffff:ffff:ffff:ffff:ffff:ffff
25332af:fc::/3232af:fc:ffff:ffff:ffff:ffff:ffff:ffff
25432af:fd::/3232af:fd:ffff:ffff:ffff:ffff:ffff:ffff
25532af:fe::/3232af:fe:ffff:ffff:ffff:ffff:ffff:ffff
25632af:ff::/3232af:ff: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.