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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:d915:d200/119
First address
2c19:dd:d9:dd:c25:c25:d915:d200
Last address
2c19:dd:d9:dd:c25:c25:d915:d3ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:d200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.d.5.1.9.d.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.d.5.1.9.d.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:d915:d200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:d200/1272c19:dd:d9:dd:c25:c25:d915:d201
22c19:dd:d9:dd:c25:c25:d915:d202/1272c19:dd:d9:dd:c25:c25:d915:d203
32c19:dd:d9:dd:c25:c25:d915:d204/1272c19:dd:d9:dd:c25:c25:d915:d205
42c19:dd:d9:dd:c25:c25:d915:d206/1272c19:dd:d9:dd:c25:c25:d915:d207
52c19:dd:d9:dd:c25:c25:d915:d208/1272c19:dd:d9:dd:c25:c25:d915:d209
62c19:dd:d9:dd:c25:c25:d915:d20a/1272c19:dd:d9:dd:c25:c25:d915:d20b
72c19:dd:d9:dd:c25:c25:d915:d20c/1272c19:dd:d9:dd:c25:c25:d915:d20d
82c19:dd:d9:dd:c25:c25:d915:d20e/1272c19:dd:d9:dd:c25:c25:d915:d20f
92c19:dd:d9:dd:c25:c25:d915:d210/1272c19:dd:d9:dd:c25:c25:d915:d211
102c19:dd:d9:dd:c25:c25:d915:d212/1272c19:dd:d9:dd:c25:c25:d915:d213
112c19:dd:d9:dd:c25:c25:d915:d214/1272c19:dd:d9:dd:c25:c25:d915:d215
122c19:dd:d9:dd:c25:c25:d915:d216/1272c19:dd:d9:dd:c25:c25:d915:d217
132c19:dd:d9:dd:c25:c25:d915:d218/1272c19:dd:d9:dd:c25:c25:d915:d219
142c19:dd:d9:dd:c25:c25:d915:d21a/1272c19:dd:d9:dd:c25:c25:d915:d21b
152c19:dd:d9:dd:c25:c25:d915:d21c/1272c19:dd:d9:dd:c25:c25:d915:d21d
162c19:dd:d9:dd:c25:c25:d915:d21e/1272c19:dd:d9:dd:c25:c25:d915:d21f
172c19:dd:d9:dd:c25:c25:d915:d220/1272c19:dd:d9:dd:c25:c25:d915:d221
182c19:dd:d9:dd:c25:c25:d915:d222/1272c19:dd:d9:dd:c25:c25:d915:d223
192c19:dd:d9:dd:c25:c25:d915:d224/1272c19:dd:d9:dd:c25:c25:d915:d225
202c19:dd:d9:dd:c25:c25:d915:d226/1272c19:dd:d9:dd:c25:c25:d915:d227
212c19:dd:d9:dd:c25:c25:d915:d228/1272c19:dd:d9:dd:c25:c25:d915:d229
222c19:dd:d9:dd:c25:c25:d915:d22a/1272c19:dd:d9:dd:c25:c25:d915:d22b
232c19:dd:d9:dd:c25:c25:d915:d22c/1272c19:dd:d9:dd:c25:c25:d915:d22d
242c19:dd:d9:dd:c25:c25:d915:d22e/1272c19:dd:d9:dd:c25:c25:d915:d22f
252c19:dd:d9:dd:c25:c25:d915:d230/1272c19:dd:d9:dd:c25:c25:d915:d231
262c19:dd:d9:dd:c25:c25:d915:d232/1272c19:dd:d9:dd:c25:c25:d915:d233
272c19:dd:d9:dd:c25:c25:d915:d234/1272c19:dd:d9:dd:c25:c25:d915:d235
282c19:dd:d9:dd:c25:c25:d915:d236/1272c19:dd:d9:dd:c25:c25:d915:d237
292c19:dd:d9:dd:c25:c25:d915:d238/1272c19:dd:d9:dd:c25:c25:d915:d239
302c19:dd:d9:dd:c25:c25:d915:d23a/1272c19:dd:d9:dd:c25:c25:d915:d23b
312c19:dd:d9:dd:c25:c25:d915:d23c/1272c19:dd:d9:dd:c25:c25:d915:d23d
322c19:dd:d9:dd:c25:c25:d915:d23e/1272c19:dd:d9:dd:c25:c25:d915:d23f
332c19:dd:d9:dd:c25:c25:d915:d240/1272c19:dd:d9:dd:c25:c25:d915:d241
342c19:dd:d9:dd:c25:c25:d915:d242/1272c19:dd:d9:dd:c25:c25:d915:d243
352c19:dd:d9:dd:c25:c25:d915:d244/1272c19:dd:d9:dd:c25:c25:d915:d245
362c19:dd:d9:dd:c25:c25:d915:d246/1272c19:dd:d9:dd:c25:c25:d915:d247
372c19:dd:d9:dd:c25:c25:d915:d248/1272c19:dd:d9:dd:c25:c25:d915:d249
382c19:dd:d9:dd:c25:c25:d915:d24a/1272c19:dd:d9:dd:c25:c25:d915:d24b
392c19:dd:d9:dd:c25:c25:d915:d24c/1272c19:dd:d9:dd:c25:c25:d915:d24d
402c19:dd:d9:dd:c25:c25:d915:d24e/1272c19:dd:d9:dd:c25:c25:d915:d24f
412c19:dd:d9:dd:c25:c25:d915:d250/1272c19:dd:d9:dd:c25:c25:d915:d251
422c19:dd:d9:dd:c25:c25:d915:d252/1272c19:dd:d9:dd:c25:c25:d915:d253
432c19:dd:d9:dd:c25:c25:d915:d254/1272c19:dd:d9:dd:c25:c25:d915:d255
442c19:dd:d9:dd:c25:c25:d915:d256/1272c19:dd:d9:dd:c25:c25:d915:d257
452c19:dd:d9:dd:c25:c25:d915:d258/1272c19:dd:d9:dd:c25:c25:d915:d259
462c19:dd:d9:dd:c25:c25:d915:d25a/1272c19:dd:d9:dd:c25:c25:d915:d25b
472c19:dd:d9:dd:c25:c25:d915:d25c/1272c19:dd:d9:dd:c25:c25:d915:d25d
482c19:dd:d9:dd:c25:c25:d915:d25e/1272c19:dd:d9:dd:c25:c25:d915:d25f
492c19:dd:d9:dd:c25:c25:d915:d260/1272c19:dd:d9:dd:c25:c25:d915:d261
502c19:dd:d9:dd:c25:c25:d915:d262/1272c19:dd:d9:dd:c25:c25:d915:d263
512c19:dd:d9:dd:c25:c25:d915:d264/1272c19:dd:d9:dd:c25:c25:d915:d265
522c19:dd:d9:dd:c25:c25:d915:d266/1272c19:dd:d9:dd:c25:c25:d915:d267
532c19:dd:d9:dd:c25:c25:d915:d268/1272c19:dd:d9:dd:c25:c25:d915:d269
542c19:dd:d9:dd:c25:c25:d915:d26a/1272c19:dd:d9:dd:c25:c25:d915:d26b
552c19:dd:d9:dd:c25:c25:d915:d26c/1272c19:dd:d9:dd:c25:c25:d915:d26d
562c19:dd:d9:dd:c25:c25:d915:d26e/1272c19:dd:d9:dd:c25:c25:d915:d26f
572c19:dd:d9:dd:c25:c25:d915:d270/1272c19:dd:d9:dd:c25:c25:d915:d271
582c19:dd:d9:dd:c25:c25:d915:d272/1272c19:dd:d9:dd:c25:c25:d915:d273
592c19:dd:d9:dd:c25:c25:d915:d274/1272c19:dd:d9:dd:c25:c25:d915:d275
602c19:dd:d9:dd:c25:c25:d915:d276/1272c19:dd:d9:dd:c25:c25:d915:d277
612c19:dd:d9:dd:c25:c25:d915:d278/1272c19:dd:d9:dd:c25:c25:d915:d279
622c19:dd:d9:dd:c25:c25:d915:d27a/1272c19:dd:d9:dd:c25:c25:d915:d27b
632c19:dd:d9:dd:c25:c25:d915:d27c/1272c19:dd:d9:dd:c25:c25:d915:d27d
642c19:dd:d9:dd:c25:c25:d915:d27e/1272c19:dd:d9:dd:c25:c25:d915:d27f
652c19:dd:d9:dd:c25:c25:d915:d280/1272c19:dd:d9:dd:c25:c25:d915:d281
662c19:dd:d9:dd:c25:c25:d915:d282/1272c19:dd:d9:dd:c25:c25:d915:d283
672c19:dd:d9:dd:c25:c25:d915:d284/1272c19:dd:d9:dd:c25:c25:d915:d285
682c19:dd:d9:dd:c25:c25:d915:d286/1272c19:dd:d9:dd:c25:c25:d915:d287
692c19:dd:d9:dd:c25:c25:d915:d288/1272c19:dd:d9:dd:c25:c25:d915:d289
702c19:dd:d9:dd:c25:c25:d915:d28a/1272c19:dd:d9:dd:c25:c25:d915:d28b
712c19:dd:d9:dd:c25:c25:d915:d28c/1272c19:dd:d9:dd:c25:c25:d915:d28d
722c19:dd:d9:dd:c25:c25:d915:d28e/1272c19:dd:d9:dd:c25:c25:d915:d28f
732c19:dd:d9:dd:c25:c25:d915:d290/1272c19:dd:d9:dd:c25:c25:d915:d291
742c19:dd:d9:dd:c25:c25:d915:d292/1272c19:dd:d9:dd:c25:c25:d915:d293
752c19:dd:d9:dd:c25:c25:d915:d294/1272c19:dd:d9:dd:c25:c25:d915:d295
762c19:dd:d9:dd:c25:c25:d915:d296/1272c19:dd:d9:dd:c25:c25:d915:d297
772c19:dd:d9:dd:c25:c25:d915:d298/1272c19:dd:d9:dd:c25:c25:d915:d299
782c19:dd:d9:dd:c25:c25:d915:d29a/1272c19:dd:d9:dd:c25:c25:d915:d29b
792c19:dd:d9:dd:c25:c25:d915:d29c/1272c19:dd:d9:dd:c25:c25:d915:d29d
802c19:dd:d9:dd:c25:c25:d915:d29e/1272c19:dd:d9:dd:c25:c25:d915:d29f
812c19:dd:d9:dd:c25:c25:d915:d2a0/1272c19:dd:d9:dd:c25:c25:d915:d2a1
822c19:dd:d9:dd:c25:c25:d915:d2a2/1272c19:dd:d9:dd:c25:c25:d915:d2a3
832c19:dd:d9:dd:c25:c25:d915:d2a4/1272c19:dd:d9:dd:c25:c25:d915:d2a5
842c19:dd:d9:dd:c25:c25:d915:d2a6/1272c19:dd:d9:dd:c25:c25:d915:d2a7
852c19:dd:d9:dd:c25:c25:d915:d2a8/1272c19:dd:d9:dd:c25:c25:d915:d2a9
862c19:dd:d9:dd:c25:c25:d915:d2aa/1272c19:dd:d9:dd:c25:c25:d915:d2ab
872c19:dd:d9:dd:c25:c25:d915:d2ac/1272c19:dd:d9:dd:c25:c25:d915:d2ad
882c19:dd:d9:dd:c25:c25:d915:d2ae/1272c19:dd:d9:dd:c25:c25:d915:d2af
892c19:dd:d9:dd:c25:c25:d915:d2b0/1272c19:dd:d9:dd:c25:c25:d915:d2b1
902c19:dd:d9:dd:c25:c25:d915:d2b2/1272c19:dd:d9:dd:c25:c25:d915:d2b3
912c19:dd:d9:dd:c25:c25:d915:d2b4/1272c19:dd:d9:dd:c25:c25:d915:d2b5
922c19:dd:d9:dd:c25:c25:d915:d2b6/1272c19:dd:d9:dd:c25:c25:d915:d2b7
932c19:dd:d9:dd:c25:c25:d915:d2b8/1272c19:dd:d9:dd:c25:c25:d915:d2b9
942c19:dd:d9:dd:c25:c25:d915:d2ba/1272c19:dd:d9:dd:c25:c25:d915:d2bb
952c19:dd:d9:dd:c25:c25:d915:d2bc/1272c19:dd:d9:dd:c25:c25:d915:d2bd
962c19:dd:d9:dd:c25:c25:d915:d2be/1272c19:dd:d9:dd:c25:c25:d915:d2bf
972c19:dd:d9:dd:c25:c25:d915:d2c0/1272c19:dd:d9:dd:c25:c25:d915:d2c1
982c19:dd:d9:dd:c25:c25:d915:d2c2/1272c19:dd:d9:dd:c25:c25:d915:d2c3
992c19:dd:d9:dd:c25:c25:d915:d2c4/1272c19:dd:d9:dd:c25:c25:d915:d2c5
1002c19:dd:d9:dd:c25:c25:d915:d2c6/1272c19:dd:d9:dd:c25:c25:d915:d2c7
1012c19:dd:d9:dd:c25:c25:d915:d2c8/1272c19:dd:d9:dd:c25:c25:d915:d2c9
1022c19:dd:d9:dd:c25:c25:d915:d2ca/1272c19:dd:d9:dd:c25:c25:d915:d2cb
1032c19:dd:d9:dd:c25:c25:d915:d2cc/1272c19:dd:d9:dd:c25:c25:d915:d2cd
1042c19:dd:d9:dd:c25:c25:d915:d2ce/1272c19:dd:d9:dd:c25:c25:d915:d2cf
1052c19:dd:d9:dd:c25:c25:d915:d2d0/1272c19:dd:d9:dd:c25:c25:d915:d2d1
1062c19:dd:d9:dd:c25:c25:d915:d2d2/1272c19:dd:d9:dd:c25:c25:d915:d2d3
1072c19:dd:d9:dd:c25:c25:d915:d2d4/1272c19:dd:d9:dd:c25:c25:d915:d2d5
1082c19:dd:d9:dd:c25:c25:d915:d2d6/1272c19:dd:d9:dd:c25:c25:d915:d2d7
1092c19:dd:d9:dd:c25:c25:d915:d2d8/1272c19:dd:d9:dd:c25:c25:d915:d2d9
1102c19:dd:d9:dd:c25:c25:d915:d2da/1272c19:dd:d9:dd:c25:c25:d915:d2db
1112c19:dd:d9:dd:c25:c25:d915:d2dc/1272c19:dd:d9:dd:c25:c25:d915:d2dd
1122c19:dd:d9:dd:c25:c25:d915:d2de/1272c19:dd:d9:dd:c25:c25:d915:d2df
1132c19:dd:d9:dd:c25:c25:d915:d2e0/1272c19:dd:d9:dd:c25:c25:d915:d2e1
1142c19:dd:d9:dd:c25:c25:d915:d2e2/1272c19:dd:d9:dd:c25:c25:d915:d2e3
1152c19:dd:d9:dd:c25:c25:d915:d2e4/1272c19:dd:d9:dd:c25:c25:d915:d2e5
1162c19:dd:d9:dd:c25:c25:d915:d2e6/1272c19:dd:d9:dd:c25:c25:d915:d2e7
1172c19:dd:d9:dd:c25:c25:d915:d2e8/1272c19:dd:d9:dd:c25:c25:d915:d2e9
1182c19:dd:d9:dd:c25:c25:d915:d2ea/1272c19:dd:d9:dd:c25:c25:d915:d2eb
1192c19:dd:d9:dd:c25:c25:d915:d2ec/1272c19:dd:d9:dd:c25:c25:d915:d2ed
1202c19:dd:d9:dd:c25:c25:d915:d2ee/1272c19:dd:d9:dd:c25:c25:d915:d2ef
1212c19:dd:d9:dd:c25:c25:d915:d2f0/1272c19:dd:d9:dd:c25:c25:d915:d2f1
1222c19:dd:d9:dd:c25:c25:d915:d2f2/1272c19:dd:d9:dd:c25:c25:d915:d2f3
1232c19:dd:d9:dd:c25:c25:d915:d2f4/1272c19:dd:d9:dd:c25:c25:d915:d2f5
1242c19:dd:d9:dd:c25:c25:d915:d2f6/1272c19:dd:d9:dd:c25:c25:d915:d2f7
1252c19:dd:d9:dd:c25:c25:d915:d2f8/1272c19:dd:d9:dd:c25:c25:d915:d2f9
1262c19:dd:d9:dd:c25:c25:d915:d2fa/1272c19:dd:d9:dd:c25:c25:d915:d2fb
1272c19:dd:d9:dd:c25:c25:d915:d2fc/1272c19:dd:d9:dd:c25:c25:d915:d2fd
1282c19:dd:d9:dd:c25:c25:d915:d2fe/1272c19:dd:d9:dd:c25:c25:d915:d2ff
1292c19:dd:d9:dd:c25:c25:d915:d300/1272c19:dd:d9:dd:c25:c25:d915:d301
1302c19:dd:d9:dd:c25:c25:d915:d302/1272c19:dd:d9:dd:c25:c25:d915:d303
1312c19:dd:d9:dd:c25:c25:d915:d304/1272c19:dd:d9:dd:c25:c25:d915:d305
1322c19:dd:d9:dd:c25:c25:d915:d306/1272c19:dd:d9:dd:c25:c25:d915:d307
1332c19:dd:d9:dd:c25:c25:d915:d308/1272c19:dd:d9:dd:c25:c25:d915:d309
1342c19:dd:d9:dd:c25:c25:d915:d30a/1272c19:dd:d9:dd:c25:c25:d915:d30b
1352c19:dd:d9:dd:c25:c25:d915:d30c/1272c19:dd:d9:dd:c25:c25:d915:d30d
1362c19:dd:d9:dd:c25:c25:d915:d30e/1272c19:dd:d9:dd:c25:c25:d915:d30f
1372c19:dd:d9:dd:c25:c25:d915:d310/1272c19:dd:d9:dd:c25:c25:d915:d311
1382c19:dd:d9:dd:c25:c25:d915:d312/1272c19:dd:d9:dd:c25:c25:d915:d313
1392c19:dd:d9:dd:c25:c25:d915:d314/1272c19:dd:d9:dd:c25:c25:d915:d315
1402c19:dd:d9:dd:c25:c25:d915:d316/1272c19:dd:d9:dd:c25:c25:d915:d317
1412c19:dd:d9:dd:c25:c25:d915:d318/1272c19:dd:d9:dd:c25:c25:d915:d319
1422c19:dd:d9:dd:c25:c25:d915:d31a/1272c19:dd:d9:dd:c25:c25:d915:d31b
1432c19:dd:d9:dd:c25:c25:d915:d31c/1272c19:dd:d9:dd:c25:c25:d915:d31d
1442c19:dd:d9:dd:c25:c25:d915:d31e/1272c19:dd:d9:dd:c25:c25:d915:d31f
1452c19:dd:d9:dd:c25:c25:d915:d320/1272c19:dd:d9:dd:c25:c25:d915:d321
1462c19:dd:d9:dd:c25:c25:d915:d322/1272c19:dd:d9:dd:c25:c25:d915:d323
1472c19:dd:d9:dd:c25:c25:d915:d324/1272c19:dd:d9:dd:c25:c25:d915:d325
1482c19:dd:d9:dd:c25:c25:d915:d326/1272c19:dd:d9:dd:c25:c25:d915:d327
1492c19:dd:d9:dd:c25:c25:d915:d328/1272c19:dd:d9:dd:c25:c25:d915:d329
1502c19:dd:d9:dd:c25:c25:d915:d32a/1272c19:dd:d9:dd:c25:c25:d915:d32b
1512c19:dd:d9:dd:c25:c25:d915:d32c/1272c19:dd:d9:dd:c25:c25:d915:d32d
1522c19:dd:d9:dd:c25:c25:d915:d32e/1272c19:dd:d9:dd:c25:c25:d915:d32f
1532c19:dd:d9:dd:c25:c25:d915:d330/1272c19:dd:d9:dd:c25:c25:d915:d331
1542c19:dd:d9:dd:c25:c25:d915:d332/1272c19:dd:d9:dd:c25:c25:d915:d333
1552c19:dd:d9:dd:c25:c25:d915:d334/1272c19:dd:d9:dd:c25:c25:d915:d335
1562c19:dd:d9:dd:c25:c25:d915:d336/1272c19:dd:d9:dd:c25:c25:d915:d337
1572c19:dd:d9:dd:c25:c25:d915:d338/1272c19:dd:d9:dd:c25:c25:d915:d339
1582c19:dd:d9:dd:c25:c25:d915:d33a/1272c19:dd:d9:dd:c25:c25:d915:d33b
1592c19:dd:d9:dd:c25:c25:d915:d33c/1272c19:dd:d9:dd:c25:c25:d915:d33d
1602c19:dd:d9:dd:c25:c25:d915:d33e/1272c19:dd:d9:dd:c25:c25:d915:d33f
1612c19:dd:d9:dd:c25:c25:d915:d340/1272c19:dd:d9:dd:c25:c25:d915:d341
1622c19:dd:d9:dd:c25:c25:d915:d342/1272c19:dd:d9:dd:c25:c25:d915:d343
1632c19:dd:d9:dd:c25:c25:d915:d344/1272c19:dd:d9:dd:c25:c25:d915:d345
1642c19:dd:d9:dd:c25:c25:d915:d346/1272c19:dd:d9:dd:c25:c25:d915:d347
1652c19:dd:d9:dd:c25:c25:d915:d348/1272c19:dd:d9:dd:c25:c25:d915:d349
1662c19:dd:d9:dd:c25:c25:d915:d34a/1272c19:dd:d9:dd:c25:c25:d915:d34b
1672c19:dd:d9:dd:c25:c25:d915:d34c/1272c19:dd:d9:dd:c25:c25:d915:d34d
1682c19:dd:d9:dd:c25:c25:d915:d34e/1272c19:dd:d9:dd:c25:c25:d915:d34f
1692c19:dd:d9:dd:c25:c25:d915:d350/1272c19:dd:d9:dd:c25:c25:d915:d351
1702c19:dd:d9:dd:c25:c25:d915:d352/1272c19:dd:d9:dd:c25:c25:d915:d353
1712c19:dd:d9:dd:c25:c25:d915:d354/1272c19:dd:d9:dd:c25:c25:d915:d355
1722c19:dd:d9:dd:c25:c25:d915:d356/1272c19:dd:d9:dd:c25:c25:d915:d357
1732c19:dd:d9:dd:c25:c25:d915:d358/1272c19:dd:d9:dd:c25:c25:d915:d359
1742c19:dd:d9:dd:c25:c25:d915:d35a/1272c19:dd:d9:dd:c25:c25:d915:d35b
1752c19:dd:d9:dd:c25:c25:d915:d35c/1272c19:dd:d9:dd:c25:c25:d915:d35d
1762c19:dd:d9:dd:c25:c25:d915:d35e/1272c19:dd:d9:dd:c25:c25:d915:d35f
1772c19:dd:d9:dd:c25:c25:d915:d360/1272c19:dd:d9:dd:c25:c25:d915:d361
1782c19:dd:d9:dd:c25:c25:d915:d362/1272c19:dd:d9:dd:c25:c25:d915:d363
1792c19:dd:d9:dd:c25:c25:d915:d364/1272c19:dd:d9:dd:c25:c25:d915:d365
1802c19:dd:d9:dd:c25:c25:d915:d366/1272c19:dd:d9:dd:c25:c25:d915:d367
1812c19:dd:d9:dd:c25:c25:d915:d368/1272c19:dd:d9:dd:c25:c25:d915:d369
1822c19:dd:d9:dd:c25:c25:d915:d36a/1272c19:dd:d9:dd:c25:c25:d915:d36b
1832c19:dd:d9:dd:c25:c25:d915:d36c/1272c19:dd:d9:dd:c25:c25:d915:d36d
1842c19:dd:d9:dd:c25:c25:d915:d36e/1272c19:dd:d9:dd:c25:c25:d915:d36f
1852c19:dd:d9:dd:c25:c25:d915:d370/1272c19:dd:d9:dd:c25:c25:d915:d371
1862c19:dd:d9:dd:c25:c25:d915:d372/1272c19:dd:d9:dd:c25:c25:d915:d373
1872c19:dd:d9:dd:c25:c25:d915:d374/1272c19:dd:d9:dd:c25:c25:d915:d375
1882c19:dd:d9:dd:c25:c25:d915:d376/1272c19:dd:d9:dd:c25:c25:d915:d377
1892c19:dd:d9:dd:c25:c25:d915:d378/1272c19:dd:d9:dd:c25:c25:d915:d379
1902c19:dd:d9:dd:c25:c25:d915:d37a/1272c19:dd:d9:dd:c25:c25:d915:d37b
1912c19:dd:d9:dd:c25:c25:d915:d37c/1272c19:dd:d9:dd:c25:c25:d915:d37d
1922c19:dd:d9:dd:c25:c25:d915:d37e/1272c19:dd:d9:dd:c25:c25:d915:d37f
1932c19:dd:d9:dd:c25:c25:d915:d380/1272c19:dd:d9:dd:c25:c25:d915:d381
1942c19:dd:d9:dd:c25:c25:d915:d382/1272c19:dd:d9:dd:c25:c25:d915:d383
1952c19:dd:d9:dd:c25:c25:d915:d384/1272c19:dd:d9:dd:c25:c25:d915:d385
1962c19:dd:d9:dd:c25:c25:d915:d386/1272c19:dd:d9:dd:c25:c25:d915:d387
1972c19:dd:d9:dd:c25:c25:d915:d388/1272c19:dd:d9:dd:c25:c25:d915:d389
1982c19:dd:d9:dd:c25:c25:d915:d38a/1272c19:dd:d9:dd:c25:c25:d915:d38b
1992c19:dd:d9:dd:c25:c25:d915:d38c/1272c19:dd:d9:dd:c25:c25:d915:d38d
2002c19:dd:d9:dd:c25:c25:d915:d38e/1272c19:dd:d9:dd:c25:c25:d915:d38f
2012c19:dd:d9:dd:c25:c25:d915:d390/1272c19:dd:d9:dd:c25:c25:d915:d391
2022c19:dd:d9:dd:c25:c25:d915:d392/1272c19:dd:d9:dd:c25:c25:d915:d393
2032c19:dd:d9:dd:c25:c25:d915:d394/1272c19:dd:d9:dd:c25:c25:d915:d395
2042c19:dd:d9:dd:c25:c25:d915:d396/1272c19:dd:d9:dd:c25:c25:d915:d397
2052c19:dd:d9:dd:c25:c25:d915:d398/1272c19:dd:d9:dd:c25:c25:d915:d399
2062c19:dd:d9:dd:c25:c25:d915:d39a/1272c19:dd:d9:dd:c25:c25:d915:d39b
2072c19:dd:d9:dd:c25:c25:d915:d39c/1272c19:dd:d9:dd:c25:c25:d915:d39d
2082c19:dd:d9:dd:c25:c25:d915:d39e/1272c19:dd:d9:dd:c25:c25:d915:d39f
2092c19:dd:d9:dd:c25:c25:d915:d3a0/1272c19:dd:d9:dd:c25:c25:d915:d3a1
2102c19:dd:d9:dd:c25:c25:d915:d3a2/1272c19:dd:d9:dd:c25:c25:d915:d3a3
2112c19:dd:d9:dd:c25:c25:d915:d3a4/1272c19:dd:d9:dd:c25:c25:d915:d3a5
2122c19:dd:d9:dd:c25:c25:d915:d3a6/1272c19:dd:d9:dd:c25:c25:d915:d3a7
2132c19:dd:d9:dd:c25:c25:d915:d3a8/1272c19:dd:d9:dd:c25:c25:d915:d3a9
2142c19:dd:d9:dd:c25:c25:d915:d3aa/1272c19:dd:d9:dd:c25:c25:d915:d3ab
2152c19:dd:d9:dd:c25:c25:d915:d3ac/1272c19:dd:d9:dd:c25:c25:d915:d3ad
2162c19:dd:d9:dd:c25:c25:d915:d3ae/1272c19:dd:d9:dd:c25:c25:d915:d3af
2172c19:dd:d9:dd:c25:c25:d915:d3b0/1272c19:dd:d9:dd:c25:c25:d915:d3b1
2182c19:dd:d9:dd:c25:c25:d915:d3b2/1272c19:dd:d9:dd:c25:c25:d915:d3b3
2192c19:dd:d9:dd:c25:c25:d915:d3b4/1272c19:dd:d9:dd:c25:c25:d915:d3b5
2202c19:dd:d9:dd:c25:c25:d915:d3b6/1272c19:dd:d9:dd:c25:c25:d915:d3b7
2212c19:dd:d9:dd:c25:c25:d915:d3b8/1272c19:dd:d9:dd:c25:c25:d915:d3b9
2222c19:dd:d9:dd:c25:c25:d915:d3ba/1272c19:dd:d9:dd:c25:c25:d915:d3bb
2232c19:dd:d9:dd:c25:c25:d915:d3bc/1272c19:dd:d9:dd:c25:c25:d915:d3bd
2242c19:dd:d9:dd:c25:c25:d915:d3be/1272c19:dd:d9:dd:c25:c25:d915:d3bf
2252c19:dd:d9:dd:c25:c25:d915:d3c0/1272c19:dd:d9:dd:c25:c25:d915:d3c1
2262c19:dd:d9:dd:c25:c25:d915:d3c2/1272c19:dd:d9:dd:c25:c25:d915:d3c3
2272c19:dd:d9:dd:c25:c25:d915:d3c4/1272c19:dd:d9:dd:c25:c25:d915:d3c5
2282c19:dd:d9:dd:c25:c25:d915:d3c6/1272c19:dd:d9:dd:c25:c25:d915:d3c7
2292c19:dd:d9:dd:c25:c25:d915:d3c8/1272c19:dd:d9:dd:c25:c25:d915:d3c9
2302c19:dd:d9:dd:c25:c25:d915:d3ca/1272c19:dd:d9:dd:c25:c25:d915:d3cb
2312c19:dd:d9:dd:c25:c25:d915:d3cc/1272c19:dd:d9:dd:c25:c25:d915:d3cd
2322c19:dd:d9:dd:c25:c25:d915:d3ce/1272c19:dd:d9:dd:c25:c25:d915:d3cf
2332c19:dd:d9:dd:c25:c25:d915:d3d0/1272c19:dd:d9:dd:c25:c25:d915:d3d1
2342c19:dd:d9:dd:c25:c25:d915:d3d2/1272c19:dd:d9:dd:c25:c25:d915:d3d3
2352c19:dd:d9:dd:c25:c25:d915:d3d4/1272c19:dd:d9:dd:c25:c25:d915:d3d5
2362c19:dd:d9:dd:c25:c25:d915:d3d6/1272c19:dd:d9:dd:c25:c25:d915:d3d7
2372c19:dd:d9:dd:c25:c25:d915:d3d8/1272c19:dd:d9:dd:c25:c25:d915:d3d9
2382c19:dd:d9:dd:c25:c25:d915:d3da/1272c19:dd:d9:dd:c25:c25:d915:d3db
2392c19:dd:d9:dd:c25:c25:d915:d3dc/1272c19:dd:d9:dd:c25:c25:d915:d3dd
2402c19:dd:d9:dd:c25:c25:d915:d3de/1272c19:dd:d9:dd:c25:c25:d915:d3df
2412c19:dd:d9:dd:c25:c25:d915:d3e0/1272c19:dd:d9:dd:c25:c25:d915:d3e1
2422c19:dd:d9:dd:c25:c25:d915:d3e2/1272c19:dd:d9:dd:c25:c25:d915:d3e3
2432c19:dd:d9:dd:c25:c25:d915:d3e4/1272c19:dd:d9:dd:c25:c25:d915:d3e5
2442c19:dd:d9:dd:c25:c25:d915:d3e6/1272c19:dd:d9:dd:c25:c25:d915:d3e7
2452c19:dd:d9:dd:c25:c25:d915:d3e8/1272c19:dd:d9:dd:c25:c25:d915:d3e9
2462c19:dd:d9:dd:c25:c25:d915:d3ea/1272c19:dd:d9:dd:c25:c25:d915:d3eb
2472c19:dd:d9:dd:c25:c25:d915:d3ec/1272c19:dd:d9:dd:c25:c25:d915:d3ed
2482c19:dd:d9:dd:c25:c25:d915:d3ee/1272c19:dd:d9:dd:c25:c25:d915:d3ef
2492c19:dd:d9:dd:c25:c25:d915:d3f0/1272c19:dd:d9:dd:c25:c25:d915:d3f1
2502c19:dd:d9:dd:c25:c25:d915:d3f2/1272c19:dd:d9:dd:c25:c25:d915:d3f3
2512c19:dd:d9:dd:c25:c25:d915:d3f4/1272c19:dd:d9:dd:c25:c25:d915:d3f5
2522c19:dd:d9:dd:c25:c25:d915:d3f6/1272c19:dd:d9:dd:c25:c25:d915:d3f7
2532c19:dd:d9:dd:c25:c25:d915:d3f8/1272c19:dd:d9:dd:c25:c25:d915:d3f9
2542c19:dd:d9:dd:c25:c25:d915:d3fa/1272c19:dd:d9:dd:c25:c25:d915:d3fb
2552c19:dd:d9:dd:c25:c25:d915:d3fc/1272c19:dd:d9:dd:c25:c25:d915:d3fd
2562c19:dd:d9:dd:c25:c25:d915:d3fe/1272c19:dd:d9:dd:c25:c25:d915:d3ff

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.