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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:b200/119
First address
2c19:dd:d9:dd:c25:c25:94de:b200
Last address
2c19:dd:d9:dd:c25:c25:94de:b3ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.b.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
3.b.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:b200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b200/1272c19:dd:d9:dd:c25:c25:94de:b201
22c19:dd:d9:dd:c25:c25:94de:b202/1272c19:dd:d9:dd:c25:c25:94de:b203
32c19:dd:d9:dd:c25:c25:94de:b204/1272c19:dd:d9:dd:c25:c25:94de:b205
42c19:dd:d9:dd:c25:c25:94de:b206/1272c19:dd:d9:dd:c25:c25:94de:b207
52c19:dd:d9:dd:c25:c25:94de:b208/1272c19:dd:d9:dd:c25:c25:94de:b209
62c19:dd:d9:dd:c25:c25:94de:b20a/1272c19:dd:d9:dd:c25:c25:94de:b20b
72c19:dd:d9:dd:c25:c25:94de:b20c/1272c19:dd:d9:dd:c25:c25:94de:b20d
82c19:dd:d9:dd:c25:c25:94de:b20e/1272c19:dd:d9:dd:c25:c25:94de:b20f
92c19:dd:d9:dd:c25:c25:94de:b210/1272c19:dd:d9:dd:c25:c25:94de:b211
102c19:dd:d9:dd:c25:c25:94de:b212/1272c19:dd:d9:dd:c25:c25:94de:b213
112c19:dd:d9:dd:c25:c25:94de:b214/1272c19:dd:d9:dd:c25:c25:94de:b215
122c19:dd:d9:dd:c25:c25:94de:b216/1272c19:dd:d9:dd:c25:c25:94de:b217
132c19:dd:d9:dd:c25:c25:94de:b218/1272c19:dd:d9:dd:c25:c25:94de:b219
142c19:dd:d9:dd:c25:c25:94de:b21a/1272c19:dd:d9:dd:c25:c25:94de:b21b
152c19:dd:d9:dd:c25:c25:94de:b21c/1272c19:dd:d9:dd:c25:c25:94de:b21d
162c19:dd:d9:dd:c25:c25:94de:b21e/1272c19:dd:d9:dd:c25:c25:94de:b21f
172c19:dd:d9:dd:c25:c25:94de:b220/1272c19:dd:d9:dd:c25:c25:94de:b221
182c19:dd:d9:dd:c25:c25:94de:b222/1272c19:dd:d9:dd:c25:c25:94de:b223
192c19:dd:d9:dd:c25:c25:94de:b224/1272c19:dd:d9:dd:c25:c25:94de:b225
202c19:dd:d9:dd:c25:c25:94de:b226/1272c19:dd:d9:dd:c25:c25:94de:b227
212c19:dd:d9:dd:c25:c25:94de:b228/1272c19:dd:d9:dd:c25:c25:94de:b229
222c19:dd:d9:dd:c25:c25:94de:b22a/1272c19:dd:d9:dd:c25:c25:94de:b22b
232c19:dd:d9:dd:c25:c25:94de:b22c/1272c19:dd:d9:dd:c25:c25:94de:b22d
242c19:dd:d9:dd:c25:c25:94de:b22e/1272c19:dd:d9:dd:c25:c25:94de:b22f
252c19:dd:d9:dd:c25:c25:94de:b230/1272c19:dd:d9:dd:c25:c25:94de:b231
262c19:dd:d9:dd:c25:c25:94de:b232/1272c19:dd:d9:dd:c25:c25:94de:b233
272c19:dd:d9:dd:c25:c25:94de:b234/1272c19:dd:d9:dd:c25:c25:94de:b235
282c19:dd:d9:dd:c25:c25:94de:b236/1272c19:dd:d9:dd:c25:c25:94de:b237
292c19:dd:d9:dd:c25:c25:94de:b238/1272c19:dd:d9:dd:c25:c25:94de:b239
302c19:dd:d9:dd:c25:c25:94de:b23a/1272c19:dd:d9:dd:c25:c25:94de:b23b
312c19:dd:d9:dd:c25:c25:94de:b23c/1272c19:dd:d9:dd:c25:c25:94de:b23d
322c19:dd:d9:dd:c25:c25:94de:b23e/1272c19:dd:d9:dd:c25:c25:94de:b23f
332c19:dd:d9:dd:c25:c25:94de:b240/1272c19:dd:d9:dd:c25:c25:94de:b241
342c19:dd:d9:dd:c25:c25:94de:b242/1272c19:dd:d9:dd:c25:c25:94de:b243
352c19:dd:d9:dd:c25:c25:94de:b244/1272c19:dd:d9:dd:c25:c25:94de:b245
362c19:dd:d9:dd:c25:c25:94de:b246/1272c19:dd:d9:dd:c25:c25:94de:b247
372c19:dd:d9:dd:c25:c25:94de:b248/1272c19:dd:d9:dd:c25:c25:94de:b249
382c19:dd:d9:dd:c25:c25:94de:b24a/1272c19:dd:d9:dd:c25:c25:94de:b24b
392c19:dd:d9:dd:c25:c25:94de:b24c/1272c19:dd:d9:dd:c25:c25:94de:b24d
402c19:dd:d9:dd:c25:c25:94de:b24e/1272c19:dd:d9:dd:c25:c25:94de:b24f
412c19:dd:d9:dd:c25:c25:94de:b250/1272c19:dd:d9:dd:c25:c25:94de:b251
422c19:dd:d9:dd:c25:c25:94de:b252/1272c19:dd:d9:dd:c25:c25:94de:b253
432c19:dd:d9:dd:c25:c25:94de:b254/1272c19:dd:d9:dd:c25:c25:94de:b255
442c19:dd:d9:dd:c25:c25:94de:b256/1272c19:dd:d9:dd:c25:c25:94de:b257
452c19:dd:d9:dd:c25:c25:94de:b258/1272c19:dd:d9:dd:c25:c25:94de:b259
462c19:dd:d9:dd:c25:c25:94de:b25a/1272c19:dd:d9:dd:c25:c25:94de:b25b
472c19:dd:d9:dd:c25:c25:94de:b25c/1272c19:dd:d9:dd:c25:c25:94de:b25d
482c19:dd:d9:dd:c25:c25:94de:b25e/1272c19:dd:d9:dd:c25:c25:94de:b25f
492c19:dd:d9:dd:c25:c25:94de:b260/1272c19:dd:d9:dd:c25:c25:94de:b261
502c19:dd:d9:dd:c25:c25:94de:b262/1272c19:dd:d9:dd:c25:c25:94de:b263
512c19:dd:d9:dd:c25:c25:94de:b264/1272c19:dd:d9:dd:c25:c25:94de:b265
522c19:dd:d9:dd:c25:c25:94de:b266/1272c19:dd:d9:dd:c25:c25:94de:b267
532c19:dd:d9:dd:c25:c25:94de:b268/1272c19:dd:d9:dd:c25:c25:94de:b269
542c19:dd:d9:dd:c25:c25:94de:b26a/1272c19:dd:d9:dd:c25:c25:94de:b26b
552c19:dd:d9:dd:c25:c25:94de:b26c/1272c19:dd:d9:dd:c25:c25:94de:b26d
562c19:dd:d9:dd:c25:c25:94de:b26e/1272c19:dd:d9:dd:c25:c25:94de:b26f
572c19:dd:d9:dd:c25:c25:94de:b270/1272c19:dd:d9:dd:c25:c25:94de:b271
582c19:dd:d9:dd:c25:c25:94de:b272/1272c19:dd:d9:dd:c25:c25:94de:b273
592c19:dd:d9:dd:c25:c25:94de:b274/1272c19:dd:d9:dd:c25:c25:94de:b275
602c19:dd:d9:dd:c25:c25:94de:b276/1272c19:dd:d9:dd:c25:c25:94de:b277
612c19:dd:d9:dd:c25:c25:94de:b278/1272c19:dd:d9:dd:c25:c25:94de:b279
622c19:dd:d9:dd:c25:c25:94de:b27a/1272c19:dd:d9:dd:c25:c25:94de:b27b
632c19:dd:d9:dd:c25:c25:94de:b27c/1272c19:dd:d9:dd:c25:c25:94de:b27d
642c19:dd:d9:dd:c25:c25:94de:b27e/1272c19:dd:d9:dd:c25:c25:94de:b27f
652c19:dd:d9:dd:c25:c25:94de:b280/1272c19:dd:d9:dd:c25:c25:94de:b281
662c19:dd:d9:dd:c25:c25:94de:b282/1272c19:dd:d9:dd:c25:c25:94de:b283
672c19:dd:d9:dd:c25:c25:94de:b284/1272c19:dd:d9:dd:c25:c25:94de:b285
682c19:dd:d9:dd:c25:c25:94de:b286/1272c19:dd:d9:dd:c25:c25:94de:b287
692c19:dd:d9:dd:c25:c25:94de:b288/1272c19:dd:d9:dd:c25:c25:94de:b289
702c19:dd:d9:dd:c25:c25:94de:b28a/1272c19:dd:d9:dd:c25:c25:94de:b28b
712c19:dd:d9:dd:c25:c25:94de:b28c/1272c19:dd:d9:dd:c25:c25:94de:b28d
722c19:dd:d9:dd:c25:c25:94de:b28e/1272c19:dd:d9:dd:c25:c25:94de:b28f
732c19:dd:d9:dd:c25:c25:94de:b290/1272c19:dd:d9:dd:c25:c25:94de:b291
742c19:dd:d9:dd:c25:c25:94de:b292/1272c19:dd:d9:dd:c25:c25:94de:b293
752c19:dd:d9:dd:c25:c25:94de:b294/1272c19:dd:d9:dd:c25:c25:94de:b295
762c19:dd:d9:dd:c25:c25:94de:b296/1272c19:dd:d9:dd:c25:c25:94de:b297
772c19:dd:d9:dd:c25:c25:94de:b298/1272c19:dd:d9:dd:c25:c25:94de:b299
782c19:dd:d9:dd:c25:c25:94de:b29a/1272c19:dd:d9:dd:c25:c25:94de:b29b
792c19:dd:d9:dd:c25:c25:94de:b29c/1272c19:dd:d9:dd:c25:c25:94de:b29d
802c19:dd:d9:dd:c25:c25:94de:b29e/1272c19:dd:d9:dd:c25:c25:94de:b29f
812c19:dd:d9:dd:c25:c25:94de:b2a0/1272c19:dd:d9:dd:c25:c25:94de:b2a1
822c19:dd:d9:dd:c25:c25:94de:b2a2/1272c19:dd:d9:dd:c25:c25:94de:b2a3
832c19:dd:d9:dd:c25:c25:94de:b2a4/1272c19:dd:d9:dd:c25:c25:94de:b2a5
842c19:dd:d9:dd:c25:c25:94de:b2a6/1272c19:dd:d9:dd:c25:c25:94de:b2a7
852c19:dd:d9:dd:c25:c25:94de:b2a8/1272c19:dd:d9:dd:c25:c25:94de:b2a9
862c19:dd:d9:dd:c25:c25:94de:b2aa/1272c19:dd:d9:dd:c25:c25:94de:b2ab
872c19:dd:d9:dd:c25:c25:94de:b2ac/1272c19:dd:d9:dd:c25:c25:94de:b2ad
882c19:dd:d9:dd:c25:c25:94de:b2ae/1272c19:dd:d9:dd:c25:c25:94de:b2af
892c19:dd:d9:dd:c25:c25:94de:b2b0/1272c19:dd:d9:dd:c25:c25:94de:b2b1
902c19:dd:d9:dd:c25:c25:94de:b2b2/1272c19:dd:d9:dd:c25:c25:94de:b2b3
912c19:dd:d9:dd:c25:c25:94de:b2b4/1272c19:dd:d9:dd:c25:c25:94de:b2b5
922c19:dd:d9:dd:c25:c25:94de:b2b6/1272c19:dd:d9:dd:c25:c25:94de:b2b7
932c19:dd:d9:dd:c25:c25:94de:b2b8/1272c19:dd:d9:dd:c25:c25:94de:b2b9
942c19:dd:d9:dd:c25:c25:94de:b2ba/1272c19:dd:d9:dd:c25:c25:94de:b2bb
952c19:dd:d9:dd:c25:c25:94de:b2bc/1272c19:dd:d9:dd:c25:c25:94de:b2bd
962c19:dd:d9:dd:c25:c25:94de:b2be/1272c19:dd:d9:dd:c25:c25:94de:b2bf
972c19:dd:d9:dd:c25:c25:94de:b2c0/1272c19:dd:d9:dd:c25:c25:94de:b2c1
982c19:dd:d9:dd:c25:c25:94de:b2c2/1272c19:dd:d9:dd:c25:c25:94de:b2c3
992c19:dd:d9:dd:c25:c25:94de:b2c4/1272c19:dd:d9:dd:c25:c25:94de:b2c5
1002c19:dd:d9:dd:c25:c25:94de:b2c6/1272c19:dd:d9:dd:c25:c25:94de:b2c7
1012c19:dd:d9:dd:c25:c25:94de:b2c8/1272c19:dd:d9:dd:c25:c25:94de:b2c9
1022c19:dd:d9:dd:c25:c25:94de:b2ca/1272c19:dd:d9:dd:c25:c25:94de:b2cb
1032c19:dd:d9:dd:c25:c25:94de:b2cc/1272c19:dd:d9:dd:c25:c25:94de:b2cd
1042c19:dd:d9:dd:c25:c25:94de:b2ce/1272c19:dd:d9:dd:c25:c25:94de:b2cf
1052c19:dd:d9:dd:c25:c25:94de:b2d0/1272c19:dd:d9:dd:c25:c25:94de:b2d1
1062c19:dd:d9:dd:c25:c25:94de:b2d2/1272c19:dd:d9:dd:c25:c25:94de:b2d3
1072c19:dd:d9:dd:c25:c25:94de:b2d4/1272c19:dd:d9:dd:c25:c25:94de:b2d5
1082c19:dd:d9:dd:c25:c25:94de:b2d6/1272c19:dd:d9:dd:c25:c25:94de:b2d7
1092c19:dd:d9:dd:c25:c25:94de:b2d8/1272c19:dd:d9:dd:c25:c25:94de:b2d9
1102c19:dd:d9:dd:c25:c25:94de:b2da/1272c19:dd:d9:dd:c25:c25:94de:b2db
1112c19:dd:d9:dd:c25:c25:94de:b2dc/1272c19:dd:d9:dd:c25:c25:94de:b2dd
1122c19:dd:d9:dd:c25:c25:94de:b2de/1272c19:dd:d9:dd:c25:c25:94de:b2df
1132c19:dd:d9:dd:c25:c25:94de:b2e0/1272c19:dd:d9:dd:c25:c25:94de:b2e1
1142c19:dd:d9:dd:c25:c25:94de:b2e2/1272c19:dd:d9:dd:c25:c25:94de:b2e3
1152c19:dd:d9:dd:c25:c25:94de:b2e4/1272c19:dd:d9:dd:c25:c25:94de:b2e5
1162c19:dd:d9:dd:c25:c25:94de:b2e6/1272c19:dd:d9:dd:c25:c25:94de:b2e7
1172c19:dd:d9:dd:c25:c25:94de:b2e8/1272c19:dd:d9:dd:c25:c25:94de:b2e9
1182c19:dd:d9:dd:c25:c25:94de:b2ea/1272c19:dd:d9:dd:c25:c25:94de:b2eb
1192c19:dd:d9:dd:c25:c25:94de:b2ec/1272c19:dd:d9:dd:c25:c25:94de:b2ed
1202c19:dd:d9:dd:c25:c25:94de:b2ee/1272c19:dd:d9:dd:c25:c25:94de:b2ef
1212c19:dd:d9:dd:c25:c25:94de:b2f0/1272c19:dd:d9:dd:c25:c25:94de:b2f1
1222c19:dd:d9:dd:c25:c25:94de:b2f2/1272c19:dd:d9:dd:c25:c25:94de:b2f3
1232c19:dd:d9:dd:c25:c25:94de:b2f4/1272c19:dd:d9:dd:c25:c25:94de:b2f5
1242c19:dd:d9:dd:c25:c25:94de:b2f6/1272c19:dd:d9:dd:c25:c25:94de:b2f7
1252c19:dd:d9:dd:c25:c25:94de:b2f8/1272c19:dd:d9:dd:c25:c25:94de:b2f9
1262c19:dd:d9:dd:c25:c25:94de:b2fa/1272c19:dd:d9:dd:c25:c25:94de:b2fb
1272c19:dd:d9:dd:c25:c25:94de:b2fc/1272c19:dd:d9:dd:c25:c25:94de:b2fd
1282c19:dd:d9:dd:c25:c25:94de:b2fe/1272c19:dd:d9:dd:c25:c25:94de:b2ff
1292c19:dd:d9:dd:c25:c25:94de:b300/1272c19:dd:d9:dd:c25:c25:94de:b301
1302c19:dd:d9:dd:c25:c25:94de:b302/1272c19:dd:d9:dd:c25:c25:94de:b303
1312c19:dd:d9:dd:c25:c25:94de:b304/1272c19:dd:d9:dd:c25:c25:94de:b305
1322c19:dd:d9:dd:c25:c25:94de:b306/1272c19:dd:d9:dd:c25:c25:94de:b307
1332c19:dd:d9:dd:c25:c25:94de:b308/1272c19:dd:d9:dd:c25:c25:94de:b309
1342c19:dd:d9:dd:c25:c25:94de:b30a/1272c19:dd:d9:dd:c25:c25:94de:b30b
1352c19:dd:d9:dd:c25:c25:94de:b30c/1272c19:dd:d9:dd:c25:c25:94de:b30d
1362c19:dd:d9:dd:c25:c25:94de:b30e/1272c19:dd:d9:dd:c25:c25:94de:b30f
1372c19:dd:d9:dd:c25:c25:94de:b310/1272c19:dd:d9:dd:c25:c25:94de:b311
1382c19:dd:d9:dd:c25:c25:94de:b312/1272c19:dd:d9:dd:c25:c25:94de:b313
1392c19:dd:d9:dd:c25:c25:94de:b314/1272c19:dd:d9:dd:c25:c25:94de:b315
1402c19:dd:d9:dd:c25:c25:94de:b316/1272c19:dd:d9:dd:c25:c25:94de:b317
1412c19:dd:d9:dd:c25:c25:94de:b318/1272c19:dd:d9:dd:c25:c25:94de:b319
1422c19:dd:d9:dd:c25:c25:94de:b31a/1272c19:dd:d9:dd:c25:c25:94de:b31b
1432c19:dd:d9:dd:c25:c25:94de:b31c/1272c19:dd:d9:dd:c25:c25:94de:b31d
1442c19:dd:d9:dd:c25:c25:94de:b31e/1272c19:dd:d9:dd:c25:c25:94de:b31f
1452c19:dd:d9:dd:c25:c25:94de:b320/1272c19:dd:d9:dd:c25:c25:94de:b321
1462c19:dd:d9:dd:c25:c25:94de:b322/1272c19:dd:d9:dd:c25:c25:94de:b323
1472c19:dd:d9:dd:c25:c25:94de:b324/1272c19:dd:d9:dd:c25:c25:94de:b325
1482c19:dd:d9:dd:c25:c25:94de:b326/1272c19:dd:d9:dd:c25:c25:94de:b327
1492c19:dd:d9:dd:c25:c25:94de:b328/1272c19:dd:d9:dd:c25:c25:94de:b329
1502c19:dd:d9:dd:c25:c25:94de:b32a/1272c19:dd:d9:dd:c25:c25:94de:b32b
1512c19:dd:d9:dd:c25:c25:94de:b32c/1272c19:dd:d9:dd:c25:c25:94de:b32d
1522c19:dd:d9:dd:c25:c25:94de:b32e/1272c19:dd:d9:dd:c25:c25:94de:b32f
1532c19:dd:d9:dd:c25:c25:94de:b330/1272c19:dd:d9:dd:c25:c25:94de:b331
1542c19:dd:d9:dd:c25:c25:94de:b332/1272c19:dd:d9:dd:c25:c25:94de:b333
1552c19:dd:d9:dd:c25:c25:94de:b334/1272c19:dd:d9:dd:c25:c25:94de:b335
1562c19:dd:d9:dd:c25:c25:94de:b336/1272c19:dd:d9:dd:c25:c25:94de:b337
1572c19:dd:d9:dd:c25:c25:94de:b338/1272c19:dd:d9:dd:c25:c25:94de:b339
1582c19:dd:d9:dd:c25:c25:94de:b33a/1272c19:dd:d9:dd:c25:c25:94de:b33b
1592c19:dd:d9:dd:c25:c25:94de:b33c/1272c19:dd:d9:dd:c25:c25:94de:b33d
1602c19:dd:d9:dd:c25:c25:94de:b33e/1272c19:dd:d9:dd:c25:c25:94de:b33f
1612c19:dd:d9:dd:c25:c25:94de:b340/1272c19:dd:d9:dd:c25:c25:94de:b341
1622c19:dd:d9:dd:c25:c25:94de:b342/1272c19:dd:d9:dd:c25:c25:94de:b343
1632c19:dd:d9:dd:c25:c25:94de:b344/1272c19:dd:d9:dd:c25:c25:94de:b345
1642c19:dd:d9:dd:c25:c25:94de:b346/1272c19:dd:d9:dd:c25:c25:94de:b347
1652c19:dd:d9:dd:c25:c25:94de:b348/1272c19:dd:d9:dd:c25:c25:94de:b349
1662c19:dd:d9:dd:c25:c25:94de:b34a/1272c19:dd:d9:dd:c25:c25:94de:b34b
1672c19:dd:d9:dd:c25:c25:94de:b34c/1272c19:dd:d9:dd:c25:c25:94de:b34d
1682c19:dd:d9:dd:c25:c25:94de:b34e/1272c19:dd:d9:dd:c25:c25:94de:b34f
1692c19:dd:d9:dd:c25:c25:94de:b350/1272c19:dd:d9:dd:c25:c25:94de:b351
1702c19:dd:d9:dd:c25:c25:94de:b352/1272c19:dd:d9:dd:c25:c25:94de:b353
1712c19:dd:d9:dd:c25:c25:94de:b354/1272c19:dd:d9:dd:c25:c25:94de:b355
1722c19:dd:d9:dd:c25:c25:94de:b356/1272c19:dd:d9:dd:c25:c25:94de:b357
1732c19:dd:d9:dd:c25:c25:94de:b358/1272c19:dd:d9:dd:c25:c25:94de:b359
1742c19:dd:d9:dd:c25:c25:94de:b35a/1272c19:dd:d9:dd:c25:c25:94de:b35b
1752c19:dd:d9:dd:c25:c25:94de:b35c/1272c19:dd:d9:dd:c25:c25:94de:b35d
1762c19:dd:d9:dd:c25:c25:94de:b35e/1272c19:dd:d9:dd:c25:c25:94de:b35f
1772c19:dd:d9:dd:c25:c25:94de:b360/1272c19:dd:d9:dd:c25:c25:94de:b361
1782c19:dd:d9:dd:c25:c25:94de:b362/1272c19:dd:d9:dd:c25:c25:94de:b363
1792c19:dd:d9:dd:c25:c25:94de:b364/1272c19:dd:d9:dd:c25:c25:94de:b365
1802c19:dd:d9:dd:c25:c25:94de:b366/1272c19:dd:d9:dd:c25:c25:94de:b367
1812c19:dd:d9:dd:c25:c25:94de:b368/1272c19:dd:d9:dd:c25:c25:94de:b369
1822c19:dd:d9:dd:c25:c25:94de:b36a/1272c19:dd:d9:dd:c25:c25:94de:b36b
1832c19:dd:d9:dd:c25:c25:94de:b36c/1272c19:dd:d9:dd:c25:c25:94de:b36d
1842c19:dd:d9:dd:c25:c25:94de:b36e/1272c19:dd:d9:dd:c25:c25:94de:b36f
1852c19:dd:d9:dd:c25:c25:94de:b370/1272c19:dd:d9:dd:c25:c25:94de:b371
1862c19:dd:d9:dd:c25:c25:94de:b372/1272c19:dd:d9:dd:c25:c25:94de:b373
1872c19:dd:d9:dd:c25:c25:94de:b374/1272c19:dd:d9:dd:c25:c25:94de:b375
1882c19:dd:d9:dd:c25:c25:94de:b376/1272c19:dd:d9:dd:c25:c25:94de:b377
1892c19:dd:d9:dd:c25:c25:94de:b378/1272c19:dd:d9:dd:c25:c25:94de:b379
1902c19:dd:d9:dd:c25:c25:94de:b37a/1272c19:dd:d9:dd:c25:c25:94de:b37b
1912c19:dd:d9:dd:c25:c25:94de:b37c/1272c19:dd:d9:dd:c25:c25:94de:b37d
1922c19:dd:d9:dd:c25:c25:94de:b37e/1272c19:dd:d9:dd:c25:c25:94de:b37f
1932c19:dd:d9:dd:c25:c25:94de:b380/1272c19:dd:d9:dd:c25:c25:94de:b381
1942c19:dd:d9:dd:c25:c25:94de:b382/1272c19:dd:d9:dd:c25:c25:94de:b383
1952c19:dd:d9:dd:c25:c25:94de:b384/1272c19:dd:d9:dd:c25:c25:94de:b385
1962c19:dd:d9:dd:c25:c25:94de:b386/1272c19:dd:d9:dd:c25:c25:94de:b387
1972c19:dd:d9:dd:c25:c25:94de:b388/1272c19:dd:d9:dd:c25:c25:94de:b389
1982c19:dd:d9:dd:c25:c25:94de:b38a/1272c19:dd:d9:dd:c25:c25:94de:b38b
1992c19:dd:d9:dd:c25:c25:94de:b38c/1272c19:dd:d9:dd:c25:c25:94de:b38d
2002c19:dd:d9:dd:c25:c25:94de:b38e/1272c19:dd:d9:dd:c25:c25:94de:b38f
2012c19:dd:d9:dd:c25:c25:94de:b390/1272c19:dd:d9:dd:c25:c25:94de:b391
2022c19:dd:d9:dd:c25:c25:94de:b392/1272c19:dd:d9:dd:c25:c25:94de:b393
2032c19:dd:d9:dd:c25:c25:94de:b394/1272c19:dd:d9:dd:c25:c25:94de:b395
2042c19:dd:d9:dd:c25:c25:94de:b396/1272c19:dd:d9:dd:c25:c25:94de:b397
2052c19:dd:d9:dd:c25:c25:94de:b398/1272c19:dd:d9:dd:c25:c25:94de:b399
2062c19:dd:d9:dd:c25:c25:94de:b39a/1272c19:dd:d9:dd:c25:c25:94de:b39b
2072c19:dd:d9:dd:c25:c25:94de:b39c/1272c19:dd:d9:dd:c25:c25:94de:b39d
2082c19:dd:d9:dd:c25:c25:94de:b39e/1272c19:dd:d9:dd:c25:c25:94de:b39f
2092c19:dd:d9:dd:c25:c25:94de:b3a0/1272c19:dd:d9:dd:c25:c25:94de:b3a1
2102c19:dd:d9:dd:c25:c25:94de:b3a2/1272c19:dd:d9:dd:c25:c25:94de:b3a3
2112c19:dd:d9:dd:c25:c25:94de:b3a4/1272c19:dd:d9:dd:c25:c25:94de:b3a5
2122c19:dd:d9:dd:c25:c25:94de:b3a6/1272c19:dd:d9:dd:c25:c25:94de:b3a7
2132c19:dd:d9:dd:c25:c25:94de:b3a8/1272c19:dd:d9:dd:c25:c25:94de:b3a9
2142c19:dd:d9:dd:c25:c25:94de:b3aa/1272c19:dd:d9:dd:c25:c25:94de:b3ab
2152c19:dd:d9:dd:c25:c25:94de:b3ac/1272c19:dd:d9:dd:c25:c25:94de:b3ad
2162c19:dd:d9:dd:c25:c25:94de:b3ae/1272c19:dd:d9:dd:c25:c25:94de:b3af
2172c19:dd:d9:dd:c25:c25:94de:b3b0/1272c19:dd:d9:dd:c25:c25:94de:b3b1
2182c19:dd:d9:dd:c25:c25:94de:b3b2/1272c19:dd:d9:dd:c25:c25:94de:b3b3
2192c19:dd:d9:dd:c25:c25:94de:b3b4/1272c19:dd:d9:dd:c25:c25:94de:b3b5
2202c19:dd:d9:dd:c25:c25:94de:b3b6/1272c19:dd:d9:dd:c25:c25:94de:b3b7
2212c19:dd:d9:dd:c25:c25:94de:b3b8/1272c19:dd:d9:dd:c25:c25:94de:b3b9
2222c19:dd:d9:dd:c25:c25:94de:b3ba/1272c19:dd:d9:dd:c25:c25:94de:b3bb
2232c19:dd:d9:dd:c25:c25:94de:b3bc/1272c19:dd:d9:dd:c25:c25:94de:b3bd
2242c19:dd:d9:dd:c25:c25:94de:b3be/1272c19:dd:d9:dd:c25:c25:94de:b3bf
2252c19:dd:d9:dd:c25:c25:94de:b3c0/1272c19:dd:d9:dd:c25:c25:94de:b3c1
2262c19:dd:d9:dd:c25:c25:94de:b3c2/1272c19:dd:d9:dd:c25:c25:94de:b3c3
2272c19:dd:d9:dd:c25:c25:94de:b3c4/1272c19:dd:d9:dd:c25:c25:94de:b3c5
2282c19:dd:d9:dd:c25:c25:94de:b3c6/1272c19:dd:d9:dd:c25:c25:94de:b3c7
2292c19:dd:d9:dd:c25:c25:94de:b3c8/1272c19:dd:d9:dd:c25:c25:94de:b3c9
2302c19:dd:d9:dd:c25:c25:94de:b3ca/1272c19:dd:d9:dd:c25:c25:94de:b3cb
2312c19:dd:d9:dd:c25:c25:94de:b3cc/1272c19:dd:d9:dd:c25:c25:94de:b3cd
2322c19:dd:d9:dd:c25:c25:94de:b3ce/1272c19:dd:d9:dd:c25:c25:94de:b3cf
2332c19:dd:d9:dd:c25:c25:94de:b3d0/1272c19:dd:d9:dd:c25:c25:94de:b3d1
2342c19:dd:d9:dd:c25:c25:94de:b3d2/1272c19:dd:d9:dd:c25:c25:94de:b3d3
2352c19:dd:d9:dd:c25:c25:94de:b3d4/1272c19:dd:d9:dd:c25:c25:94de:b3d5
2362c19:dd:d9:dd:c25:c25:94de:b3d6/1272c19:dd:d9:dd:c25:c25:94de:b3d7
2372c19:dd:d9:dd:c25:c25:94de:b3d8/1272c19:dd:d9:dd:c25:c25:94de:b3d9
2382c19:dd:d9:dd:c25:c25:94de:b3da/1272c19:dd:d9:dd:c25:c25:94de:b3db
2392c19:dd:d9:dd:c25:c25:94de:b3dc/1272c19:dd:d9:dd:c25:c25:94de:b3dd
2402c19:dd:d9:dd:c25:c25:94de:b3de/1272c19:dd:d9:dd:c25:c25:94de:b3df
2412c19:dd:d9:dd:c25:c25:94de:b3e0/1272c19:dd:d9:dd:c25:c25:94de:b3e1
2422c19:dd:d9:dd:c25:c25:94de:b3e2/1272c19:dd:d9:dd:c25:c25:94de:b3e3
2432c19:dd:d9:dd:c25:c25:94de:b3e4/1272c19:dd:d9:dd:c25:c25:94de:b3e5
2442c19:dd:d9:dd:c25:c25:94de:b3e6/1272c19:dd:d9:dd:c25:c25:94de:b3e7
2452c19:dd:d9:dd:c25:c25:94de:b3e8/1272c19:dd:d9:dd:c25:c25:94de:b3e9
2462c19:dd:d9:dd:c25:c25:94de:b3ea/1272c19:dd:d9:dd:c25:c25:94de:b3eb
2472c19:dd:d9:dd:c25:c25:94de:b3ec/1272c19:dd:d9:dd:c25:c25:94de:b3ed
2482c19:dd:d9:dd:c25:c25:94de:b3ee/1272c19:dd:d9:dd:c25:c25:94de:b3ef
2492c19:dd:d9:dd:c25:c25:94de:b3f0/1272c19:dd:d9:dd:c25:c25:94de:b3f1
2502c19:dd:d9:dd:c25:c25:94de:b3f2/1272c19:dd:d9:dd:c25:c25:94de:b3f3
2512c19:dd:d9:dd:c25:c25:94de:b3f4/1272c19:dd:d9:dd:c25:c25:94de:b3f5
2522c19:dd:d9:dd:c25:c25:94de:b3f6/1272c19:dd:d9:dd:c25:c25:94de:b3f7
2532c19:dd:d9:dd:c25:c25:94de:b3f8/1272c19:dd:d9:dd:c25:c25:94de:b3f9
2542c19:dd:d9:dd:c25:c25:94de:b3fa/1272c19:dd:d9:dd:c25:c25:94de:b3fb
2552c19:dd:d9:dd:c25:c25:94de:b3fc/1272c19:dd:d9:dd:c25:c25:94de:b3fd
2562c19:dd:d9:dd:c25:c25:94de:b3fe/1272c19:dd:d9:dd:c25:c25:94de:b3ff

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.