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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:e200/119
First address
2c19:dd:d9:dd:c25:c25:94de:e200
Last address
2c19:dd:d9:dd:c25:c25:94de:e3ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:e200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.e.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.e.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:e200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:e200/1272c19:dd:d9:dd:c25:c25:94de:e201
22c19:dd:d9:dd:c25:c25:94de:e202/1272c19:dd:d9:dd:c25:c25:94de:e203
32c19:dd:d9:dd:c25:c25:94de:e204/1272c19:dd:d9:dd:c25:c25:94de:e205
42c19:dd:d9:dd:c25:c25:94de:e206/1272c19:dd:d9:dd:c25:c25:94de:e207
52c19:dd:d9:dd:c25:c25:94de:e208/1272c19:dd:d9:dd:c25:c25:94de:e209
62c19:dd:d9:dd:c25:c25:94de:e20a/1272c19:dd:d9:dd:c25:c25:94de:e20b
72c19:dd:d9:dd:c25:c25:94de:e20c/1272c19:dd:d9:dd:c25:c25:94de:e20d
82c19:dd:d9:dd:c25:c25:94de:e20e/1272c19:dd:d9:dd:c25:c25:94de:e20f
92c19:dd:d9:dd:c25:c25:94de:e210/1272c19:dd:d9:dd:c25:c25:94de:e211
102c19:dd:d9:dd:c25:c25:94de:e212/1272c19:dd:d9:dd:c25:c25:94de:e213
112c19:dd:d9:dd:c25:c25:94de:e214/1272c19:dd:d9:dd:c25:c25:94de:e215
122c19:dd:d9:dd:c25:c25:94de:e216/1272c19:dd:d9:dd:c25:c25:94de:e217
132c19:dd:d9:dd:c25:c25:94de:e218/1272c19:dd:d9:dd:c25:c25:94de:e219
142c19:dd:d9:dd:c25:c25:94de:e21a/1272c19:dd:d9:dd:c25:c25:94de:e21b
152c19:dd:d9:dd:c25:c25:94de:e21c/1272c19:dd:d9:dd:c25:c25:94de:e21d
162c19:dd:d9:dd:c25:c25:94de:e21e/1272c19:dd:d9:dd:c25:c25:94de:e21f
172c19:dd:d9:dd:c25:c25:94de:e220/1272c19:dd:d9:dd:c25:c25:94de:e221
182c19:dd:d9:dd:c25:c25:94de:e222/1272c19:dd:d9:dd:c25:c25:94de:e223
192c19:dd:d9:dd:c25:c25:94de:e224/1272c19:dd:d9:dd:c25:c25:94de:e225
202c19:dd:d9:dd:c25:c25:94de:e226/1272c19:dd:d9:dd:c25:c25:94de:e227
212c19:dd:d9:dd:c25:c25:94de:e228/1272c19:dd:d9:dd:c25:c25:94de:e229
222c19:dd:d9:dd:c25:c25:94de:e22a/1272c19:dd:d9:dd:c25:c25:94de:e22b
232c19:dd:d9:dd:c25:c25:94de:e22c/1272c19:dd:d9:dd:c25:c25:94de:e22d
242c19:dd:d9:dd:c25:c25:94de:e22e/1272c19:dd:d9:dd:c25:c25:94de:e22f
252c19:dd:d9:dd:c25:c25:94de:e230/1272c19:dd:d9:dd:c25:c25:94de:e231
262c19:dd:d9:dd:c25:c25:94de:e232/1272c19:dd:d9:dd:c25:c25:94de:e233
272c19:dd:d9:dd:c25:c25:94de:e234/1272c19:dd:d9:dd:c25:c25:94de:e235
282c19:dd:d9:dd:c25:c25:94de:e236/1272c19:dd:d9:dd:c25:c25:94de:e237
292c19:dd:d9:dd:c25:c25:94de:e238/1272c19:dd:d9:dd:c25:c25:94de:e239
302c19:dd:d9:dd:c25:c25:94de:e23a/1272c19:dd:d9:dd:c25:c25:94de:e23b
312c19:dd:d9:dd:c25:c25:94de:e23c/1272c19:dd:d9:dd:c25:c25:94de:e23d
322c19:dd:d9:dd:c25:c25:94de:e23e/1272c19:dd:d9:dd:c25:c25:94de:e23f
332c19:dd:d9:dd:c25:c25:94de:e240/1272c19:dd:d9:dd:c25:c25:94de:e241
342c19:dd:d9:dd:c25:c25:94de:e242/1272c19:dd:d9:dd:c25:c25:94de:e243
352c19:dd:d9:dd:c25:c25:94de:e244/1272c19:dd:d9:dd:c25:c25:94de:e245
362c19:dd:d9:dd:c25:c25:94de:e246/1272c19:dd:d9:dd:c25:c25:94de:e247
372c19:dd:d9:dd:c25:c25:94de:e248/1272c19:dd:d9:dd:c25:c25:94de:e249
382c19:dd:d9:dd:c25:c25:94de:e24a/1272c19:dd:d9:dd:c25:c25:94de:e24b
392c19:dd:d9:dd:c25:c25:94de:e24c/1272c19:dd:d9:dd:c25:c25:94de:e24d
402c19:dd:d9:dd:c25:c25:94de:e24e/1272c19:dd:d9:dd:c25:c25:94de:e24f
412c19:dd:d9:dd:c25:c25:94de:e250/1272c19:dd:d9:dd:c25:c25:94de:e251
422c19:dd:d9:dd:c25:c25:94de:e252/1272c19:dd:d9:dd:c25:c25:94de:e253
432c19:dd:d9:dd:c25:c25:94de:e254/1272c19:dd:d9:dd:c25:c25:94de:e255
442c19:dd:d9:dd:c25:c25:94de:e256/1272c19:dd:d9:dd:c25:c25:94de:e257
452c19:dd:d9:dd:c25:c25:94de:e258/1272c19:dd:d9:dd:c25:c25:94de:e259
462c19:dd:d9:dd:c25:c25:94de:e25a/1272c19:dd:d9:dd:c25:c25:94de:e25b
472c19:dd:d9:dd:c25:c25:94de:e25c/1272c19:dd:d9:dd:c25:c25:94de:e25d
482c19:dd:d9:dd:c25:c25:94de:e25e/1272c19:dd:d9:dd:c25:c25:94de:e25f
492c19:dd:d9:dd:c25:c25:94de:e260/1272c19:dd:d9:dd:c25:c25:94de:e261
502c19:dd:d9:dd:c25:c25:94de:e262/1272c19:dd:d9:dd:c25:c25:94de:e263
512c19:dd:d9:dd:c25:c25:94de:e264/1272c19:dd:d9:dd:c25:c25:94de:e265
522c19:dd:d9:dd:c25:c25:94de:e266/1272c19:dd:d9:dd:c25:c25:94de:e267
532c19:dd:d9:dd:c25:c25:94de:e268/1272c19:dd:d9:dd:c25:c25:94de:e269
542c19:dd:d9:dd:c25:c25:94de:e26a/1272c19:dd:d9:dd:c25:c25:94de:e26b
552c19:dd:d9:dd:c25:c25:94de:e26c/1272c19:dd:d9:dd:c25:c25:94de:e26d
562c19:dd:d9:dd:c25:c25:94de:e26e/1272c19:dd:d9:dd:c25:c25:94de:e26f
572c19:dd:d9:dd:c25:c25:94de:e270/1272c19:dd:d9:dd:c25:c25:94de:e271
582c19:dd:d9:dd:c25:c25:94de:e272/1272c19:dd:d9:dd:c25:c25:94de:e273
592c19:dd:d9:dd:c25:c25:94de:e274/1272c19:dd:d9:dd:c25:c25:94de:e275
602c19:dd:d9:dd:c25:c25:94de:e276/1272c19:dd:d9:dd:c25:c25:94de:e277
612c19:dd:d9:dd:c25:c25:94de:e278/1272c19:dd:d9:dd:c25:c25:94de:e279
622c19:dd:d9:dd:c25:c25:94de:e27a/1272c19:dd:d9:dd:c25:c25:94de:e27b
632c19:dd:d9:dd:c25:c25:94de:e27c/1272c19:dd:d9:dd:c25:c25:94de:e27d
642c19:dd:d9:dd:c25:c25:94de:e27e/1272c19:dd:d9:dd:c25:c25:94de:e27f
652c19:dd:d9:dd:c25:c25:94de:e280/1272c19:dd:d9:dd:c25:c25:94de:e281
662c19:dd:d9:dd:c25:c25:94de:e282/1272c19:dd:d9:dd:c25:c25:94de:e283
672c19:dd:d9:dd:c25:c25:94de:e284/1272c19:dd:d9:dd:c25:c25:94de:e285
682c19:dd:d9:dd:c25:c25:94de:e286/1272c19:dd:d9:dd:c25:c25:94de:e287
692c19:dd:d9:dd:c25:c25:94de:e288/1272c19:dd:d9:dd:c25:c25:94de:e289
702c19:dd:d9:dd:c25:c25:94de:e28a/1272c19:dd:d9:dd:c25:c25:94de:e28b
712c19:dd:d9:dd:c25:c25:94de:e28c/1272c19:dd:d9:dd:c25:c25:94de:e28d
722c19:dd:d9:dd:c25:c25:94de:e28e/1272c19:dd:d9:dd:c25:c25:94de:e28f
732c19:dd:d9:dd:c25:c25:94de:e290/1272c19:dd:d9:dd:c25:c25:94de:e291
742c19:dd:d9:dd:c25:c25:94de:e292/1272c19:dd:d9:dd:c25:c25:94de:e293
752c19:dd:d9:dd:c25:c25:94de:e294/1272c19:dd:d9:dd:c25:c25:94de:e295
762c19:dd:d9:dd:c25:c25:94de:e296/1272c19:dd:d9:dd:c25:c25:94de:e297
772c19:dd:d9:dd:c25:c25:94de:e298/1272c19:dd:d9:dd:c25:c25:94de:e299
782c19:dd:d9:dd:c25:c25:94de:e29a/1272c19:dd:d9:dd:c25:c25:94de:e29b
792c19:dd:d9:dd:c25:c25:94de:e29c/1272c19:dd:d9:dd:c25:c25:94de:e29d
802c19:dd:d9:dd:c25:c25:94de:e29e/1272c19:dd:d9:dd:c25:c25:94de:e29f
812c19:dd:d9:dd:c25:c25:94de:e2a0/1272c19:dd:d9:dd:c25:c25:94de:e2a1
822c19:dd:d9:dd:c25:c25:94de:e2a2/1272c19:dd:d9:dd:c25:c25:94de:e2a3
832c19:dd:d9:dd:c25:c25:94de:e2a4/1272c19:dd:d9:dd:c25:c25:94de:e2a5
842c19:dd:d9:dd:c25:c25:94de:e2a6/1272c19:dd:d9:dd:c25:c25:94de:e2a7
852c19:dd:d9:dd:c25:c25:94de:e2a8/1272c19:dd:d9:dd:c25:c25:94de:e2a9
862c19:dd:d9:dd:c25:c25:94de:e2aa/1272c19:dd:d9:dd:c25:c25:94de:e2ab
872c19:dd:d9:dd:c25:c25:94de:e2ac/1272c19:dd:d9:dd:c25:c25:94de:e2ad
882c19:dd:d9:dd:c25:c25:94de:e2ae/1272c19:dd:d9:dd:c25:c25:94de:e2af
892c19:dd:d9:dd:c25:c25:94de:e2b0/1272c19:dd:d9:dd:c25:c25:94de:e2b1
902c19:dd:d9:dd:c25:c25:94de:e2b2/1272c19:dd:d9:dd:c25:c25:94de:e2b3
912c19:dd:d9:dd:c25:c25:94de:e2b4/1272c19:dd:d9:dd:c25:c25:94de:e2b5
922c19:dd:d9:dd:c25:c25:94de:e2b6/1272c19:dd:d9:dd:c25:c25:94de:e2b7
932c19:dd:d9:dd:c25:c25:94de:e2b8/1272c19:dd:d9:dd:c25:c25:94de:e2b9
942c19:dd:d9:dd:c25:c25:94de:e2ba/1272c19:dd:d9:dd:c25:c25:94de:e2bb
952c19:dd:d9:dd:c25:c25:94de:e2bc/1272c19:dd:d9:dd:c25:c25:94de:e2bd
962c19:dd:d9:dd:c25:c25:94de:e2be/1272c19:dd:d9:dd:c25:c25:94de:e2bf
972c19:dd:d9:dd:c25:c25:94de:e2c0/1272c19:dd:d9:dd:c25:c25:94de:e2c1
982c19:dd:d9:dd:c25:c25:94de:e2c2/1272c19:dd:d9:dd:c25:c25:94de:e2c3
992c19:dd:d9:dd:c25:c25:94de:e2c4/1272c19:dd:d9:dd:c25:c25:94de:e2c5
1002c19:dd:d9:dd:c25:c25:94de:e2c6/1272c19:dd:d9:dd:c25:c25:94de:e2c7
1012c19:dd:d9:dd:c25:c25:94de:e2c8/1272c19:dd:d9:dd:c25:c25:94de:e2c9
1022c19:dd:d9:dd:c25:c25:94de:e2ca/1272c19:dd:d9:dd:c25:c25:94de:e2cb
1032c19:dd:d9:dd:c25:c25:94de:e2cc/1272c19:dd:d9:dd:c25:c25:94de:e2cd
1042c19:dd:d9:dd:c25:c25:94de:e2ce/1272c19:dd:d9:dd:c25:c25:94de:e2cf
1052c19:dd:d9:dd:c25:c25:94de:e2d0/1272c19:dd:d9:dd:c25:c25:94de:e2d1
1062c19:dd:d9:dd:c25:c25:94de:e2d2/1272c19:dd:d9:dd:c25:c25:94de:e2d3
1072c19:dd:d9:dd:c25:c25:94de:e2d4/1272c19:dd:d9:dd:c25:c25:94de:e2d5
1082c19:dd:d9:dd:c25:c25:94de:e2d6/1272c19:dd:d9:dd:c25:c25:94de:e2d7
1092c19:dd:d9:dd:c25:c25:94de:e2d8/1272c19:dd:d9:dd:c25:c25:94de:e2d9
1102c19:dd:d9:dd:c25:c25:94de:e2da/1272c19:dd:d9:dd:c25:c25:94de:e2db
1112c19:dd:d9:dd:c25:c25:94de:e2dc/1272c19:dd:d9:dd:c25:c25:94de:e2dd
1122c19:dd:d9:dd:c25:c25:94de:e2de/1272c19:dd:d9:dd:c25:c25:94de:e2df
1132c19:dd:d9:dd:c25:c25:94de:e2e0/1272c19:dd:d9:dd:c25:c25:94de:e2e1
1142c19:dd:d9:dd:c25:c25:94de:e2e2/1272c19:dd:d9:dd:c25:c25:94de:e2e3
1152c19:dd:d9:dd:c25:c25:94de:e2e4/1272c19:dd:d9:dd:c25:c25:94de:e2e5
1162c19:dd:d9:dd:c25:c25:94de:e2e6/1272c19:dd:d9:dd:c25:c25:94de:e2e7
1172c19:dd:d9:dd:c25:c25:94de:e2e8/1272c19:dd:d9:dd:c25:c25:94de:e2e9
1182c19:dd:d9:dd:c25:c25:94de:e2ea/1272c19:dd:d9:dd:c25:c25:94de:e2eb
1192c19:dd:d9:dd:c25:c25:94de:e2ec/1272c19:dd:d9:dd:c25:c25:94de:e2ed
1202c19:dd:d9:dd:c25:c25:94de:e2ee/1272c19:dd:d9:dd:c25:c25:94de:e2ef
1212c19:dd:d9:dd:c25:c25:94de:e2f0/1272c19:dd:d9:dd:c25:c25:94de:e2f1
1222c19:dd:d9:dd:c25:c25:94de:e2f2/1272c19:dd:d9:dd:c25:c25:94de:e2f3
1232c19:dd:d9:dd:c25:c25:94de:e2f4/1272c19:dd:d9:dd:c25:c25:94de:e2f5
1242c19:dd:d9:dd:c25:c25:94de:e2f6/1272c19:dd:d9:dd:c25:c25:94de:e2f7
1252c19:dd:d9:dd:c25:c25:94de:e2f8/1272c19:dd:d9:dd:c25:c25:94de:e2f9
1262c19:dd:d9:dd:c25:c25:94de:e2fa/1272c19:dd:d9:dd:c25:c25:94de:e2fb
1272c19:dd:d9:dd:c25:c25:94de:e2fc/1272c19:dd:d9:dd:c25:c25:94de:e2fd
1282c19:dd:d9:dd:c25:c25:94de:e2fe/1272c19:dd:d9:dd:c25:c25:94de:e2ff
1292c19:dd:d9:dd:c25:c25:94de:e300/1272c19:dd:d9:dd:c25:c25:94de:e301
1302c19:dd:d9:dd:c25:c25:94de:e302/1272c19:dd:d9:dd:c25:c25:94de:e303
1312c19:dd:d9:dd:c25:c25:94de:e304/1272c19:dd:d9:dd:c25:c25:94de:e305
1322c19:dd:d9:dd:c25:c25:94de:e306/1272c19:dd:d9:dd:c25:c25:94de:e307
1332c19:dd:d9:dd:c25:c25:94de:e308/1272c19:dd:d9:dd:c25:c25:94de:e309
1342c19:dd:d9:dd:c25:c25:94de:e30a/1272c19:dd:d9:dd:c25:c25:94de:e30b
1352c19:dd:d9:dd:c25:c25:94de:e30c/1272c19:dd:d9:dd:c25:c25:94de:e30d
1362c19:dd:d9:dd:c25:c25:94de:e30e/1272c19:dd:d9:dd:c25:c25:94de:e30f
1372c19:dd:d9:dd:c25:c25:94de:e310/1272c19:dd:d9:dd:c25:c25:94de:e311
1382c19:dd:d9:dd:c25:c25:94de:e312/1272c19:dd:d9:dd:c25:c25:94de:e313
1392c19:dd:d9:dd:c25:c25:94de:e314/1272c19:dd:d9:dd:c25:c25:94de:e315
1402c19:dd:d9:dd:c25:c25:94de:e316/1272c19:dd:d9:dd:c25:c25:94de:e317
1412c19:dd:d9:dd:c25:c25:94de:e318/1272c19:dd:d9:dd:c25:c25:94de:e319
1422c19:dd:d9:dd:c25:c25:94de:e31a/1272c19:dd:d9:dd:c25:c25:94de:e31b
1432c19:dd:d9:dd:c25:c25:94de:e31c/1272c19:dd:d9:dd:c25:c25:94de:e31d
1442c19:dd:d9:dd:c25:c25:94de:e31e/1272c19:dd:d9:dd:c25:c25:94de:e31f
1452c19:dd:d9:dd:c25:c25:94de:e320/1272c19:dd:d9:dd:c25:c25:94de:e321
1462c19:dd:d9:dd:c25:c25:94de:e322/1272c19:dd:d9:dd:c25:c25:94de:e323
1472c19:dd:d9:dd:c25:c25:94de:e324/1272c19:dd:d9:dd:c25:c25:94de:e325
1482c19:dd:d9:dd:c25:c25:94de:e326/1272c19:dd:d9:dd:c25:c25:94de:e327
1492c19:dd:d9:dd:c25:c25:94de:e328/1272c19:dd:d9:dd:c25:c25:94de:e329
1502c19:dd:d9:dd:c25:c25:94de:e32a/1272c19:dd:d9:dd:c25:c25:94de:e32b
1512c19:dd:d9:dd:c25:c25:94de:e32c/1272c19:dd:d9:dd:c25:c25:94de:e32d
1522c19:dd:d9:dd:c25:c25:94de:e32e/1272c19:dd:d9:dd:c25:c25:94de:e32f
1532c19:dd:d9:dd:c25:c25:94de:e330/1272c19:dd:d9:dd:c25:c25:94de:e331
1542c19:dd:d9:dd:c25:c25:94de:e332/1272c19:dd:d9:dd:c25:c25:94de:e333
1552c19:dd:d9:dd:c25:c25:94de:e334/1272c19:dd:d9:dd:c25:c25:94de:e335
1562c19:dd:d9:dd:c25:c25:94de:e336/1272c19:dd:d9:dd:c25:c25:94de:e337
1572c19:dd:d9:dd:c25:c25:94de:e338/1272c19:dd:d9:dd:c25:c25:94de:e339
1582c19:dd:d9:dd:c25:c25:94de:e33a/1272c19:dd:d9:dd:c25:c25:94de:e33b
1592c19:dd:d9:dd:c25:c25:94de:e33c/1272c19:dd:d9:dd:c25:c25:94de:e33d
1602c19:dd:d9:dd:c25:c25:94de:e33e/1272c19:dd:d9:dd:c25:c25:94de:e33f
1612c19:dd:d9:dd:c25:c25:94de:e340/1272c19:dd:d9:dd:c25:c25:94de:e341
1622c19:dd:d9:dd:c25:c25:94de:e342/1272c19:dd:d9:dd:c25:c25:94de:e343
1632c19:dd:d9:dd:c25:c25:94de:e344/1272c19:dd:d9:dd:c25:c25:94de:e345
1642c19:dd:d9:dd:c25:c25:94de:e346/1272c19:dd:d9:dd:c25:c25:94de:e347
1652c19:dd:d9:dd:c25:c25:94de:e348/1272c19:dd:d9:dd:c25:c25:94de:e349
1662c19:dd:d9:dd:c25:c25:94de:e34a/1272c19:dd:d9:dd:c25:c25:94de:e34b
1672c19:dd:d9:dd:c25:c25:94de:e34c/1272c19:dd:d9:dd:c25:c25:94de:e34d
1682c19:dd:d9:dd:c25:c25:94de:e34e/1272c19:dd:d9:dd:c25:c25:94de:e34f
1692c19:dd:d9:dd:c25:c25:94de:e350/1272c19:dd:d9:dd:c25:c25:94de:e351
1702c19:dd:d9:dd:c25:c25:94de:e352/1272c19:dd:d9:dd:c25:c25:94de:e353
1712c19:dd:d9:dd:c25:c25:94de:e354/1272c19:dd:d9:dd:c25:c25:94de:e355
1722c19:dd:d9:dd:c25:c25:94de:e356/1272c19:dd:d9:dd:c25:c25:94de:e357
1732c19:dd:d9:dd:c25:c25:94de:e358/1272c19:dd:d9:dd:c25:c25:94de:e359
1742c19:dd:d9:dd:c25:c25:94de:e35a/1272c19:dd:d9:dd:c25:c25:94de:e35b
1752c19:dd:d9:dd:c25:c25:94de:e35c/1272c19:dd:d9:dd:c25:c25:94de:e35d
1762c19:dd:d9:dd:c25:c25:94de:e35e/1272c19:dd:d9:dd:c25:c25:94de:e35f
1772c19:dd:d9:dd:c25:c25:94de:e360/1272c19:dd:d9:dd:c25:c25:94de:e361
1782c19:dd:d9:dd:c25:c25:94de:e362/1272c19:dd:d9:dd:c25:c25:94de:e363
1792c19:dd:d9:dd:c25:c25:94de:e364/1272c19:dd:d9:dd:c25:c25:94de:e365
1802c19:dd:d9:dd:c25:c25:94de:e366/1272c19:dd:d9:dd:c25:c25:94de:e367
1812c19:dd:d9:dd:c25:c25:94de:e368/1272c19:dd:d9:dd:c25:c25:94de:e369
1822c19:dd:d9:dd:c25:c25:94de:e36a/1272c19:dd:d9:dd:c25:c25:94de:e36b
1832c19:dd:d9:dd:c25:c25:94de:e36c/1272c19:dd:d9:dd:c25:c25:94de:e36d
1842c19:dd:d9:dd:c25:c25:94de:e36e/1272c19:dd:d9:dd:c25:c25:94de:e36f
1852c19:dd:d9:dd:c25:c25:94de:e370/1272c19:dd:d9:dd:c25:c25:94de:e371
1862c19:dd:d9:dd:c25:c25:94de:e372/1272c19:dd:d9:dd:c25:c25:94de:e373
1872c19:dd:d9:dd:c25:c25:94de:e374/1272c19:dd:d9:dd:c25:c25:94de:e375
1882c19:dd:d9:dd:c25:c25:94de:e376/1272c19:dd:d9:dd:c25:c25:94de:e377
1892c19:dd:d9:dd:c25:c25:94de:e378/1272c19:dd:d9:dd:c25:c25:94de:e379
1902c19:dd:d9:dd:c25:c25:94de:e37a/1272c19:dd:d9:dd:c25:c25:94de:e37b
1912c19:dd:d9:dd:c25:c25:94de:e37c/1272c19:dd:d9:dd:c25:c25:94de:e37d
1922c19:dd:d9:dd:c25:c25:94de:e37e/1272c19:dd:d9:dd:c25:c25:94de:e37f
1932c19:dd:d9:dd:c25:c25:94de:e380/1272c19:dd:d9:dd:c25:c25:94de:e381
1942c19:dd:d9:dd:c25:c25:94de:e382/1272c19:dd:d9:dd:c25:c25:94de:e383
1952c19:dd:d9:dd:c25:c25:94de:e384/1272c19:dd:d9:dd:c25:c25:94de:e385
1962c19:dd:d9:dd:c25:c25:94de:e386/1272c19:dd:d9:dd:c25:c25:94de:e387
1972c19:dd:d9:dd:c25:c25:94de:e388/1272c19:dd:d9:dd:c25:c25:94de:e389
1982c19:dd:d9:dd:c25:c25:94de:e38a/1272c19:dd:d9:dd:c25:c25:94de:e38b
1992c19:dd:d9:dd:c25:c25:94de:e38c/1272c19:dd:d9:dd:c25:c25:94de:e38d
2002c19:dd:d9:dd:c25:c25:94de:e38e/1272c19:dd:d9:dd:c25:c25:94de:e38f
2012c19:dd:d9:dd:c25:c25:94de:e390/1272c19:dd:d9:dd:c25:c25:94de:e391
2022c19:dd:d9:dd:c25:c25:94de:e392/1272c19:dd:d9:dd:c25:c25:94de:e393
2032c19:dd:d9:dd:c25:c25:94de:e394/1272c19:dd:d9:dd:c25:c25:94de:e395
2042c19:dd:d9:dd:c25:c25:94de:e396/1272c19:dd:d9:dd:c25:c25:94de:e397
2052c19:dd:d9:dd:c25:c25:94de:e398/1272c19:dd:d9:dd:c25:c25:94de:e399
2062c19:dd:d9:dd:c25:c25:94de:e39a/1272c19:dd:d9:dd:c25:c25:94de:e39b
2072c19:dd:d9:dd:c25:c25:94de:e39c/1272c19:dd:d9:dd:c25:c25:94de:e39d
2082c19:dd:d9:dd:c25:c25:94de:e39e/1272c19:dd:d9:dd:c25:c25:94de:e39f
2092c19:dd:d9:dd:c25:c25:94de:e3a0/1272c19:dd:d9:dd:c25:c25:94de:e3a1
2102c19:dd:d9:dd:c25:c25:94de:e3a2/1272c19:dd:d9:dd:c25:c25:94de:e3a3
2112c19:dd:d9:dd:c25:c25:94de:e3a4/1272c19:dd:d9:dd:c25:c25:94de:e3a5
2122c19:dd:d9:dd:c25:c25:94de:e3a6/1272c19:dd:d9:dd:c25:c25:94de:e3a7
2132c19:dd:d9:dd:c25:c25:94de:e3a8/1272c19:dd:d9:dd:c25:c25:94de:e3a9
2142c19:dd:d9:dd:c25:c25:94de:e3aa/1272c19:dd:d9:dd:c25:c25:94de:e3ab
2152c19:dd:d9:dd:c25:c25:94de:e3ac/1272c19:dd:d9:dd:c25:c25:94de:e3ad
2162c19:dd:d9:dd:c25:c25:94de:e3ae/1272c19:dd:d9:dd:c25:c25:94de:e3af
2172c19:dd:d9:dd:c25:c25:94de:e3b0/1272c19:dd:d9:dd:c25:c25:94de:e3b1
2182c19:dd:d9:dd:c25:c25:94de:e3b2/1272c19:dd:d9:dd:c25:c25:94de:e3b3
2192c19:dd:d9:dd:c25:c25:94de:e3b4/1272c19:dd:d9:dd:c25:c25:94de:e3b5
2202c19:dd:d9:dd:c25:c25:94de:e3b6/1272c19:dd:d9:dd:c25:c25:94de:e3b7
2212c19:dd:d9:dd:c25:c25:94de:e3b8/1272c19:dd:d9:dd:c25:c25:94de:e3b9
2222c19:dd:d9:dd:c25:c25:94de:e3ba/1272c19:dd:d9:dd:c25:c25:94de:e3bb
2232c19:dd:d9:dd:c25:c25:94de:e3bc/1272c19:dd:d9:dd:c25:c25:94de:e3bd
2242c19:dd:d9:dd:c25:c25:94de:e3be/1272c19:dd:d9:dd:c25:c25:94de:e3bf
2252c19:dd:d9:dd:c25:c25:94de:e3c0/1272c19:dd:d9:dd:c25:c25:94de:e3c1
2262c19:dd:d9:dd:c25:c25:94de:e3c2/1272c19:dd:d9:dd:c25:c25:94de:e3c3
2272c19:dd:d9:dd:c25:c25:94de:e3c4/1272c19:dd:d9:dd:c25:c25:94de:e3c5
2282c19:dd:d9:dd:c25:c25:94de:e3c6/1272c19:dd:d9:dd:c25:c25:94de:e3c7
2292c19:dd:d9:dd:c25:c25:94de:e3c8/1272c19:dd:d9:dd:c25:c25:94de:e3c9
2302c19:dd:d9:dd:c25:c25:94de:e3ca/1272c19:dd:d9:dd:c25:c25:94de:e3cb
2312c19:dd:d9:dd:c25:c25:94de:e3cc/1272c19:dd:d9:dd:c25:c25:94de:e3cd
2322c19:dd:d9:dd:c25:c25:94de:e3ce/1272c19:dd:d9:dd:c25:c25:94de:e3cf
2332c19:dd:d9:dd:c25:c25:94de:e3d0/1272c19:dd:d9:dd:c25:c25:94de:e3d1
2342c19:dd:d9:dd:c25:c25:94de:e3d2/1272c19:dd:d9:dd:c25:c25:94de:e3d3
2352c19:dd:d9:dd:c25:c25:94de:e3d4/1272c19:dd:d9:dd:c25:c25:94de:e3d5
2362c19:dd:d9:dd:c25:c25:94de:e3d6/1272c19:dd:d9:dd:c25:c25:94de:e3d7
2372c19:dd:d9:dd:c25:c25:94de:e3d8/1272c19:dd:d9:dd:c25:c25:94de:e3d9
2382c19:dd:d9:dd:c25:c25:94de:e3da/1272c19:dd:d9:dd:c25:c25:94de:e3db
2392c19:dd:d9:dd:c25:c25:94de:e3dc/1272c19:dd:d9:dd:c25:c25:94de:e3dd
2402c19:dd:d9:dd:c25:c25:94de:e3de/1272c19:dd:d9:dd:c25:c25:94de:e3df
2412c19:dd:d9:dd:c25:c25:94de:e3e0/1272c19:dd:d9:dd:c25:c25:94de:e3e1
2422c19:dd:d9:dd:c25:c25:94de:e3e2/1272c19:dd:d9:dd:c25:c25:94de:e3e3
2432c19:dd:d9:dd:c25:c25:94de:e3e4/1272c19:dd:d9:dd:c25:c25:94de:e3e5
2442c19:dd:d9:dd:c25:c25:94de:e3e6/1272c19:dd:d9:dd:c25:c25:94de:e3e7
2452c19:dd:d9:dd:c25:c25:94de:e3e8/1272c19:dd:d9:dd:c25:c25:94de:e3e9
2462c19:dd:d9:dd:c25:c25:94de:e3ea/1272c19:dd:d9:dd:c25:c25:94de:e3eb
2472c19:dd:d9:dd:c25:c25:94de:e3ec/1272c19:dd:d9:dd:c25:c25:94de:e3ed
2482c19:dd:d9:dd:c25:c25:94de:e3ee/1272c19:dd:d9:dd:c25:c25:94de:e3ef
2492c19:dd:d9:dd:c25:c25:94de:e3f0/1272c19:dd:d9:dd:c25:c25:94de:e3f1
2502c19:dd:d9:dd:c25:c25:94de:e3f2/1272c19:dd:d9:dd:c25:c25:94de:e3f3
2512c19:dd:d9:dd:c25:c25:94de:e3f4/1272c19:dd:d9:dd:c25:c25:94de:e3f5
2522c19:dd:d9:dd:c25:c25:94de:e3f6/1272c19:dd:d9:dd:c25:c25:94de:e3f7
2532c19:dd:d9:dd:c25:c25:94de:e3f8/1272c19:dd:d9:dd:c25:c25:94de:e3f9
2542c19:dd:d9:dd:c25:c25:94de:e3fa/1272c19:dd:d9:dd:c25:c25:94de:e3fb
2552c19:dd:d9:dd:c25:c25:94de:e3fc/1272c19:dd:d9:dd:c25:c25:94de:e3fd
2562c19:dd:d9:dd:c25:c25:94de:e3fe/1272c19:dd:d9:dd:c25:c25:94de:e3ff

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.