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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25a:d00a:d200/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:d200
Last address
2c19:dd:d9:dd:c25:c25a:d00a:d2ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:d200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.d.a.0.0.d.a.5.2.c.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25a:d00a:d200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:d200/1282c19:dd:d9:dd:c25:c25a:d00a:d200
22c19:dd:d9:dd:c25:c25a:d00a:d201/1282c19:dd:d9:dd:c25:c25a:d00a:d201
32c19:dd:d9:dd:c25:c25a:d00a:d202/1282c19:dd:d9:dd:c25:c25a:d00a:d202
42c19:dd:d9:dd:c25:c25a:d00a:d203/1282c19:dd:d9:dd:c25:c25a:d00a:d203
52c19:dd:d9:dd:c25:c25a:d00a:d204/1282c19:dd:d9:dd:c25:c25a:d00a:d204
62c19:dd:d9:dd:c25:c25a:d00a:d205/1282c19:dd:d9:dd:c25:c25a:d00a:d205
72c19:dd:d9:dd:c25:c25a:d00a:d206/1282c19:dd:d9:dd:c25:c25a:d00a:d206
82c19:dd:d9:dd:c25:c25a:d00a:d207/1282c19:dd:d9:dd:c25:c25a:d00a:d207
92c19:dd:d9:dd:c25:c25a:d00a:d208/1282c19:dd:d9:dd:c25:c25a:d00a:d208
102c19:dd:d9:dd:c25:c25a:d00a:d209/1282c19:dd:d9:dd:c25:c25a:d00a:d209
112c19:dd:d9:dd:c25:c25a:d00a:d20a/1282c19:dd:d9:dd:c25:c25a:d00a:d20a
122c19:dd:d9:dd:c25:c25a:d00a:d20b/1282c19:dd:d9:dd:c25:c25a:d00a:d20b
132c19:dd:d9:dd:c25:c25a:d00a:d20c/1282c19:dd:d9:dd:c25:c25a:d00a:d20c
142c19:dd:d9:dd:c25:c25a:d00a:d20d/1282c19:dd:d9:dd:c25:c25a:d00a:d20d
152c19:dd:d9:dd:c25:c25a:d00a:d20e/1282c19:dd:d9:dd:c25:c25a:d00a:d20e
162c19:dd:d9:dd:c25:c25a:d00a:d20f/1282c19:dd:d9:dd:c25:c25a:d00a:d20f
172c19:dd:d9:dd:c25:c25a:d00a:d210/1282c19:dd:d9:dd:c25:c25a:d00a:d210
182c19:dd:d9:dd:c25:c25a:d00a:d211/1282c19:dd:d9:dd:c25:c25a:d00a:d211
192c19:dd:d9:dd:c25:c25a:d00a:d212/1282c19:dd:d9:dd:c25:c25a:d00a:d212
202c19:dd:d9:dd:c25:c25a:d00a:d213/1282c19:dd:d9:dd:c25:c25a:d00a:d213
212c19:dd:d9:dd:c25:c25a:d00a:d214/1282c19:dd:d9:dd:c25:c25a:d00a:d214
222c19:dd:d9:dd:c25:c25a:d00a:d215/1282c19:dd:d9:dd:c25:c25a:d00a:d215
232c19:dd:d9:dd:c25:c25a:d00a:d216/1282c19:dd:d9:dd:c25:c25a:d00a:d216
242c19:dd:d9:dd:c25:c25a:d00a:d217/1282c19:dd:d9:dd:c25:c25a:d00a:d217
252c19:dd:d9:dd:c25:c25a:d00a:d218/1282c19:dd:d9:dd:c25:c25a:d00a:d218
262c19:dd:d9:dd:c25:c25a:d00a:d219/1282c19:dd:d9:dd:c25:c25a:d00a:d219
272c19:dd:d9:dd:c25:c25a:d00a:d21a/1282c19:dd:d9:dd:c25:c25a:d00a:d21a
282c19:dd:d9:dd:c25:c25a:d00a:d21b/1282c19:dd:d9:dd:c25:c25a:d00a:d21b
292c19:dd:d9:dd:c25:c25a:d00a:d21c/1282c19:dd:d9:dd:c25:c25a:d00a:d21c
302c19:dd:d9:dd:c25:c25a:d00a:d21d/1282c19:dd:d9:dd:c25:c25a:d00a:d21d
312c19:dd:d9:dd:c25:c25a:d00a:d21e/1282c19:dd:d9:dd:c25:c25a:d00a:d21e
322c19:dd:d9:dd:c25:c25a:d00a:d21f/1282c19:dd:d9:dd:c25:c25a:d00a:d21f
332c19:dd:d9:dd:c25:c25a:d00a:d220/1282c19:dd:d9:dd:c25:c25a:d00a:d220
342c19:dd:d9:dd:c25:c25a:d00a:d221/1282c19:dd:d9:dd:c25:c25a:d00a:d221
352c19:dd:d9:dd:c25:c25a:d00a:d222/1282c19:dd:d9:dd:c25:c25a:d00a:d222
362c19:dd:d9:dd:c25:c25a:d00a:d223/1282c19:dd:d9:dd:c25:c25a:d00a:d223
372c19:dd:d9:dd:c25:c25a:d00a:d224/1282c19:dd:d9:dd:c25:c25a:d00a:d224
382c19:dd:d9:dd:c25:c25a:d00a:d225/1282c19:dd:d9:dd:c25:c25a:d00a:d225
392c19:dd:d9:dd:c25:c25a:d00a:d226/1282c19:dd:d9:dd:c25:c25a:d00a:d226
402c19:dd:d9:dd:c25:c25a:d00a:d227/1282c19:dd:d9:dd:c25:c25a:d00a:d227
412c19:dd:d9:dd:c25:c25a:d00a:d228/1282c19:dd:d9:dd:c25:c25a:d00a:d228
422c19:dd:d9:dd:c25:c25a:d00a:d229/1282c19:dd:d9:dd:c25:c25a:d00a:d229
432c19:dd:d9:dd:c25:c25a:d00a:d22a/1282c19:dd:d9:dd:c25:c25a:d00a:d22a
442c19:dd:d9:dd:c25:c25a:d00a:d22b/1282c19:dd:d9:dd:c25:c25a:d00a:d22b
452c19:dd:d9:dd:c25:c25a:d00a:d22c/1282c19:dd:d9:dd:c25:c25a:d00a:d22c
462c19:dd:d9:dd:c25:c25a:d00a:d22d/1282c19:dd:d9:dd:c25:c25a:d00a:d22d
472c19:dd:d9:dd:c25:c25a:d00a:d22e/1282c19:dd:d9:dd:c25:c25a:d00a:d22e
482c19:dd:d9:dd:c25:c25a:d00a:d22f/1282c19:dd:d9:dd:c25:c25a:d00a:d22f
492c19:dd:d9:dd:c25:c25a:d00a:d230/1282c19:dd:d9:dd:c25:c25a:d00a:d230
502c19:dd:d9:dd:c25:c25a:d00a:d231/1282c19:dd:d9:dd:c25:c25a:d00a:d231
512c19:dd:d9:dd:c25:c25a:d00a:d232/1282c19:dd:d9:dd:c25:c25a:d00a:d232
522c19:dd:d9:dd:c25:c25a:d00a:d233/1282c19:dd:d9:dd:c25:c25a:d00a:d233
532c19:dd:d9:dd:c25:c25a:d00a:d234/1282c19:dd:d9:dd:c25:c25a:d00a:d234
542c19:dd:d9:dd:c25:c25a:d00a:d235/1282c19:dd:d9:dd:c25:c25a:d00a:d235
552c19:dd:d9:dd:c25:c25a:d00a:d236/1282c19:dd:d9:dd:c25:c25a:d00a:d236
562c19:dd:d9:dd:c25:c25a:d00a:d237/1282c19:dd:d9:dd:c25:c25a:d00a:d237
572c19:dd:d9:dd:c25:c25a:d00a:d238/1282c19:dd:d9:dd:c25:c25a:d00a:d238
582c19:dd:d9:dd:c25:c25a:d00a:d239/1282c19:dd:d9:dd:c25:c25a:d00a:d239
592c19:dd:d9:dd:c25:c25a:d00a:d23a/1282c19:dd:d9:dd:c25:c25a:d00a:d23a
602c19:dd:d9:dd:c25:c25a:d00a:d23b/1282c19:dd:d9:dd:c25:c25a:d00a:d23b
612c19:dd:d9:dd:c25:c25a:d00a:d23c/1282c19:dd:d9:dd:c25:c25a:d00a:d23c
622c19:dd:d9:dd:c25:c25a:d00a:d23d/1282c19:dd:d9:dd:c25:c25a:d00a:d23d
632c19:dd:d9:dd:c25:c25a:d00a:d23e/1282c19:dd:d9:dd:c25:c25a:d00a:d23e
642c19:dd:d9:dd:c25:c25a:d00a:d23f/1282c19:dd:d9:dd:c25:c25a:d00a:d23f
652c19:dd:d9:dd:c25:c25a:d00a:d240/1282c19:dd:d9:dd:c25:c25a:d00a:d240
662c19:dd:d9:dd:c25:c25a:d00a:d241/1282c19:dd:d9:dd:c25:c25a:d00a:d241
672c19:dd:d9:dd:c25:c25a:d00a:d242/1282c19:dd:d9:dd:c25:c25a:d00a:d242
682c19:dd:d9:dd:c25:c25a:d00a:d243/1282c19:dd:d9:dd:c25:c25a:d00a:d243
692c19:dd:d9:dd:c25:c25a:d00a:d244/1282c19:dd:d9:dd:c25:c25a:d00a:d244
702c19:dd:d9:dd:c25:c25a:d00a:d245/1282c19:dd:d9:dd:c25:c25a:d00a:d245
712c19:dd:d9:dd:c25:c25a:d00a:d246/1282c19:dd:d9:dd:c25:c25a:d00a:d246
722c19:dd:d9:dd:c25:c25a:d00a:d247/1282c19:dd:d9:dd:c25:c25a:d00a:d247
732c19:dd:d9:dd:c25:c25a:d00a:d248/1282c19:dd:d9:dd:c25:c25a:d00a:d248
742c19:dd:d9:dd:c25:c25a:d00a:d249/1282c19:dd:d9:dd:c25:c25a:d00a:d249
752c19:dd:d9:dd:c25:c25a:d00a:d24a/1282c19:dd:d9:dd:c25:c25a:d00a:d24a
762c19:dd:d9:dd:c25:c25a:d00a:d24b/1282c19:dd:d9:dd:c25:c25a:d00a:d24b
772c19:dd:d9:dd:c25:c25a:d00a:d24c/1282c19:dd:d9:dd:c25:c25a:d00a:d24c
782c19:dd:d9:dd:c25:c25a:d00a:d24d/1282c19:dd:d9:dd:c25:c25a:d00a:d24d
792c19:dd:d9:dd:c25:c25a:d00a:d24e/1282c19:dd:d9:dd:c25:c25a:d00a:d24e
802c19:dd:d9:dd:c25:c25a:d00a:d24f/1282c19:dd:d9:dd:c25:c25a:d00a:d24f
812c19:dd:d9:dd:c25:c25a:d00a:d250/1282c19:dd:d9:dd:c25:c25a:d00a:d250
822c19:dd:d9:dd:c25:c25a:d00a:d251/1282c19:dd:d9:dd:c25:c25a:d00a:d251
832c19:dd:d9:dd:c25:c25a:d00a:d252/1282c19:dd:d9:dd:c25:c25a:d00a:d252
842c19:dd:d9:dd:c25:c25a:d00a:d253/1282c19:dd:d9:dd:c25:c25a:d00a:d253
852c19:dd:d9:dd:c25:c25a:d00a:d254/1282c19:dd:d9:dd:c25:c25a:d00a:d254
862c19:dd:d9:dd:c25:c25a:d00a:d255/1282c19:dd:d9:dd:c25:c25a:d00a:d255
872c19:dd:d9:dd:c25:c25a:d00a:d256/1282c19:dd:d9:dd:c25:c25a:d00a:d256
882c19:dd:d9:dd:c25:c25a:d00a:d257/1282c19:dd:d9:dd:c25:c25a:d00a:d257
892c19:dd:d9:dd:c25:c25a:d00a:d258/1282c19:dd:d9:dd:c25:c25a:d00a:d258
902c19:dd:d9:dd:c25:c25a:d00a:d259/1282c19:dd:d9:dd:c25:c25a:d00a:d259
912c19:dd:d9:dd:c25:c25a:d00a:d25a/1282c19:dd:d9:dd:c25:c25a:d00a:d25a
922c19:dd:d9:dd:c25:c25a:d00a:d25b/1282c19:dd:d9:dd:c25:c25a:d00a:d25b
932c19:dd:d9:dd:c25:c25a:d00a:d25c/1282c19:dd:d9:dd:c25:c25a:d00a:d25c
942c19:dd:d9:dd:c25:c25a:d00a:d25d/1282c19:dd:d9:dd:c25:c25a:d00a:d25d
952c19:dd:d9:dd:c25:c25a:d00a:d25e/1282c19:dd:d9:dd:c25:c25a:d00a:d25e
962c19:dd:d9:dd:c25:c25a:d00a:d25f/1282c19:dd:d9:dd:c25:c25a:d00a:d25f
972c19:dd:d9:dd:c25:c25a:d00a:d260/1282c19:dd:d9:dd:c25:c25a:d00a:d260
982c19:dd:d9:dd:c25:c25a:d00a:d261/1282c19:dd:d9:dd:c25:c25a:d00a:d261
992c19:dd:d9:dd:c25:c25a:d00a:d262/1282c19:dd:d9:dd:c25:c25a:d00a:d262
1002c19:dd:d9:dd:c25:c25a:d00a:d263/1282c19:dd:d9:dd:c25:c25a:d00a:d263
1012c19:dd:d9:dd:c25:c25a:d00a:d264/1282c19:dd:d9:dd:c25:c25a:d00a:d264
1022c19:dd:d9:dd:c25:c25a:d00a:d265/1282c19:dd:d9:dd:c25:c25a:d00a:d265
1032c19:dd:d9:dd:c25:c25a:d00a:d266/1282c19:dd:d9:dd:c25:c25a:d00a:d266
1042c19:dd:d9:dd:c25:c25a:d00a:d267/1282c19:dd:d9:dd:c25:c25a:d00a:d267
1052c19:dd:d9:dd:c25:c25a:d00a:d268/1282c19:dd:d9:dd:c25:c25a:d00a:d268
1062c19:dd:d9:dd:c25:c25a:d00a:d269/1282c19:dd:d9:dd:c25:c25a:d00a:d269
1072c19:dd:d9:dd:c25:c25a:d00a:d26a/1282c19:dd:d9:dd:c25:c25a:d00a:d26a
1082c19:dd:d9:dd:c25:c25a:d00a:d26b/1282c19:dd:d9:dd:c25:c25a:d00a:d26b
1092c19:dd:d9:dd:c25:c25a:d00a:d26c/1282c19:dd:d9:dd:c25:c25a:d00a:d26c
1102c19:dd:d9:dd:c25:c25a:d00a:d26d/1282c19:dd:d9:dd:c25:c25a:d00a:d26d
1112c19:dd:d9:dd:c25:c25a:d00a:d26e/1282c19:dd:d9:dd:c25:c25a:d00a:d26e
1122c19:dd:d9:dd:c25:c25a:d00a:d26f/1282c19:dd:d9:dd:c25:c25a:d00a:d26f
1132c19:dd:d9:dd:c25:c25a:d00a:d270/1282c19:dd:d9:dd:c25:c25a:d00a:d270
1142c19:dd:d9:dd:c25:c25a:d00a:d271/1282c19:dd:d9:dd:c25:c25a:d00a:d271
1152c19:dd:d9:dd:c25:c25a:d00a:d272/1282c19:dd:d9:dd:c25:c25a:d00a:d272
1162c19:dd:d9:dd:c25:c25a:d00a:d273/1282c19:dd:d9:dd:c25:c25a:d00a:d273
1172c19:dd:d9:dd:c25:c25a:d00a:d274/1282c19:dd:d9:dd:c25:c25a:d00a:d274
1182c19:dd:d9:dd:c25:c25a:d00a:d275/1282c19:dd:d9:dd:c25:c25a:d00a:d275
1192c19:dd:d9:dd:c25:c25a:d00a:d276/1282c19:dd:d9:dd:c25:c25a:d00a:d276
1202c19:dd:d9:dd:c25:c25a:d00a:d277/1282c19:dd:d9:dd:c25:c25a:d00a:d277
1212c19:dd:d9:dd:c25:c25a:d00a:d278/1282c19:dd:d9:dd:c25:c25a:d00a:d278
1222c19:dd:d9:dd:c25:c25a:d00a:d279/1282c19:dd:d9:dd:c25:c25a:d00a:d279
1232c19:dd:d9:dd:c25:c25a:d00a:d27a/1282c19:dd:d9:dd:c25:c25a:d00a:d27a
1242c19:dd:d9:dd:c25:c25a:d00a:d27b/1282c19:dd:d9:dd:c25:c25a:d00a:d27b
1252c19:dd:d9:dd:c25:c25a:d00a:d27c/1282c19:dd:d9:dd:c25:c25a:d00a:d27c
1262c19:dd:d9:dd:c25:c25a:d00a:d27d/1282c19:dd:d9:dd:c25:c25a:d00a:d27d
1272c19:dd:d9:dd:c25:c25a:d00a:d27e/1282c19:dd:d9:dd:c25:c25a:d00a:d27e
1282c19:dd:d9:dd:c25:c25a:d00a:d27f/1282c19:dd:d9:dd:c25:c25a:d00a:d27f
1292c19:dd:d9:dd:c25:c25a:d00a:d280/1282c19:dd:d9:dd:c25:c25a:d00a:d280
1302c19:dd:d9:dd:c25:c25a:d00a:d281/1282c19:dd:d9:dd:c25:c25a:d00a:d281
1312c19:dd:d9:dd:c25:c25a:d00a:d282/1282c19:dd:d9:dd:c25:c25a:d00a:d282
1322c19:dd:d9:dd:c25:c25a:d00a:d283/1282c19:dd:d9:dd:c25:c25a:d00a:d283
1332c19:dd:d9:dd:c25:c25a:d00a:d284/1282c19:dd:d9:dd:c25:c25a:d00a:d284
1342c19:dd:d9:dd:c25:c25a:d00a:d285/1282c19:dd:d9:dd:c25:c25a:d00a:d285
1352c19:dd:d9:dd:c25:c25a:d00a:d286/1282c19:dd:d9:dd:c25:c25a:d00a:d286
1362c19:dd:d9:dd:c25:c25a:d00a:d287/1282c19:dd:d9:dd:c25:c25a:d00a:d287
1372c19:dd:d9:dd:c25:c25a:d00a:d288/1282c19:dd:d9:dd:c25:c25a:d00a:d288
1382c19:dd:d9:dd:c25:c25a:d00a:d289/1282c19:dd:d9:dd:c25:c25a:d00a:d289
1392c19:dd:d9:dd:c25:c25a:d00a:d28a/1282c19:dd:d9:dd:c25:c25a:d00a:d28a
1402c19:dd:d9:dd:c25:c25a:d00a:d28b/1282c19:dd:d9:dd:c25:c25a:d00a:d28b
1412c19:dd:d9:dd:c25:c25a:d00a:d28c/1282c19:dd:d9:dd:c25:c25a:d00a:d28c
1422c19:dd:d9:dd:c25:c25a:d00a:d28d/1282c19:dd:d9:dd:c25:c25a:d00a:d28d
1432c19:dd:d9:dd:c25:c25a:d00a:d28e/1282c19:dd:d9:dd:c25:c25a:d00a:d28e
1442c19:dd:d9:dd:c25:c25a:d00a:d28f/1282c19:dd:d9:dd:c25:c25a:d00a:d28f
1452c19:dd:d9:dd:c25:c25a:d00a:d290/1282c19:dd:d9:dd:c25:c25a:d00a:d290
1462c19:dd:d9:dd:c25:c25a:d00a:d291/1282c19:dd:d9:dd:c25:c25a:d00a:d291
1472c19:dd:d9:dd:c25:c25a:d00a:d292/1282c19:dd:d9:dd:c25:c25a:d00a:d292
1482c19:dd:d9:dd:c25:c25a:d00a:d293/1282c19:dd:d9:dd:c25:c25a:d00a:d293
1492c19:dd:d9:dd:c25:c25a:d00a:d294/1282c19:dd:d9:dd:c25:c25a:d00a:d294
1502c19:dd:d9:dd:c25:c25a:d00a:d295/1282c19:dd:d9:dd:c25:c25a:d00a:d295
1512c19:dd:d9:dd:c25:c25a:d00a:d296/1282c19:dd:d9:dd:c25:c25a:d00a:d296
1522c19:dd:d9:dd:c25:c25a:d00a:d297/1282c19:dd:d9:dd:c25:c25a:d00a:d297
1532c19:dd:d9:dd:c25:c25a:d00a:d298/1282c19:dd:d9:dd:c25:c25a:d00a:d298
1542c19:dd:d9:dd:c25:c25a:d00a:d299/1282c19:dd:d9:dd:c25:c25a:d00a:d299
1552c19:dd:d9:dd:c25:c25a:d00a:d29a/1282c19:dd:d9:dd:c25:c25a:d00a:d29a
1562c19:dd:d9:dd:c25:c25a:d00a:d29b/1282c19:dd:d9:dd:c25:c25a:d00a:d29b
1572c19:dd:d9:dd:c25:c25a:d00a:d29c/1282c19:dd:d9:dd:c25:c25a:d00a:d29c
1582c19:dd:d9:dd:c25:c25a:d00a:d29d/1282c19:dd:d9:dd:c25:c25a:d00a:d29d
1592c19:dd:d9:dd:c25:c25a:d00a:d29e/1282c19:dd:d9:dd:c25:c25a:d00a:d29e
1602c19:dd:d9:dd:c25:c25a:d00a:d29f/1282c19:dd:d9:dd:c25:c25a:d00a:d29f
1612c19:dd:d9:dd:c25:c25a:d00a:d2a0/1282c19:dd:d9:dd:c25:c25a:d00a:d2a0
1622c19:dd:d9:dd:c25:c25a:d00a:d2a1/1282c19:dd:d9:dd:c25:c25a:d00a:d2a1
1632c19:dd:d9:dd:c25:c25a:d00a:d2a2/1282c19:dd:d9:dd:c25:c25a:d00a:d2a2
1642c19:dd:d9:dd:c25:c25a:d00a:d2a3/1282c19:dd:d9:dd:c25:c25a:d00a:d2a3
1652c19:dd:d9:dd:c25:c25a:d00a:d2a4/1282c19:dd:d9:dd:c25:c25a:d00a:d2a4
1662c19:dd:d9:dd:c25:c25a:d00a:d2a5/1282c19:dd:d9:dd:c25:c25a:d00a:d2a5
1672c19:dd:d9:dd:c25:c25a:d00a:d2a6/1282c19:dd:d9:dd:c25:c25a:d00a:d2a6
1682c19:dd:d9:dd:c25:c25a:d00a:d2a7/1282c19:dd:d9:dd:c25:c25a:d00a:d2a7
1692c19:dd:d9:dd:c25:c25a:d00a:d2a8/1282c19:dd:d9:dd:c25:c25a:d00a:d2a8
1702c19:dd:d9:dd:c25:c25a:d00a:d2a9/1282c19:dd:d9:dd:c25:c25a:d00a:d2a9
1712c19:dd:d9:dd:c25:c25a:d00a:d2aa/1282c19:dd:d9:dd:c25:c25a:d00a:d2aa
1722c19:dd:d9:dd:c25:c25a:d00a:d2ab/1282c19:dd:d9:dd:c25:c25a:d00a:d2ab
1732c19:dd:d9:dd:c25:c25a:d00a:d2ac/1282c19:dd:d9:dd:c25:c25a:d00a:d2ac
1742c19:dd:d9:dd:c25:c25a:d00a:d2ad/1282c19:dd:d9:dd:c25:c25a:d00a:d2ad
1752c19:dd:d9:dd:c25:c25a:d00a:d2ae/1282c19:dd:d9:dd:c25:c25a:d00a:d2ae
1762c19:dd:d9:dd:c25:c25a:d00a:d2af/1282c19:dd:d9:dd:c25:c25a:d00a:d2af
1772c19:dd:d9:dd:c25:c25a:d00a:d2b0/1282c19:dd:d9:dd:c25:c25a:d00a:d2b0
1782c19:dd:d9:dd:c25:c25a:d00a:d2b1/1282c19:dd:d9:dd:c25:c25a:d00a:d2b1
1792c19:dd:d9:dd:c25:c25a:d00a:d2b2/1282c19:dd:d9:dd:c25:c25a:d00a:d2b2
1802c19:dd:d9:dd:c25:c25a:d00a:d2b3/1282c19:dd:d9:dd:c25:c25a:d00a:d2b3
1812c19:dd:d9:dd:c25:c25a:d00a:d2b4/1282c19:dd:d9:dd:c25:c25a:d00a:d2b4
1822c19:dd:d9:dd:c25:c25a:d00a:d2b5/1282c19:dd:d9:dd:c25:c25a:d00a:d2b5
1832c19:dd:d9:dd:c25:c25a:d00a:d2b6/1282c19:dd:d9:dd:c25:c25a:d00a:d2b6
1842c19:dd:d9:dd:c25:c25a:d00a:d2b7/1282c19:dd:d9:dd:c25:c25a:d00a:d2b7
1852c19:dd:d9:dd:c25:c25a:d00a:d2b8/1282c19:dd:d9:dd:c25:c25a:d00a:d2b8
1862c19:dd:d9:dd:c25:c25a:d00a:d2b9/1282c19:dd:d9:dd:c25:c25a:d00a:d2b9
1872c19:dd:d9:dd:c25:c25a:d00a:d2ba/1282c19:dd:d9:dd:c25:c25a:d00a:d2ba
1882c19:dd:d9:dd:c25:c25a:d00a:d2bb/1282c19:dd:d9:dd:c25:c25a:d00a:d2bb
1892c19:dd:d9:dd:c25:c25a:d00a:d2bc/1282c19:dd:d9:dd:c25:c25a:d00a:d2bc
1902c19:dd:d9:dd:c25:c25a:d00a:d2bd/1282c19:dd:d9:dd:c25:c25a:d00a:d2bd
1912c19:dd:d9:dd:c25:c25a:d00a:d2be/1282c19:dd:d9:dd:c25:c25a:d00a:d2be
1922c19:dd:d9:dd:c25:c25a:d00a:d2bf/1282c19:dd:d9:dd:c25:c25a:d00a:d2bf
1932c19:dd:d9:dd:c25:c25a:d00a:d2c0/1282c19:dd:d9:dd:c25:c25a:d00a:d2c0
1942c19:dd:d9:dd:c25:c25a:d00a:d2c1/1282c19:dd:d9:dd:c25:c25a:d00a:d2c1
1952c19:dd:d9:dd:c25:c25a:d00a:d2c2/1282c19:dd:d9:dd:c25:c25a:d00a:d2c2
1962c19:dd:d9:dd:c25:c25a:d00a:d2c3/1282c19:dd:d9:dd:c25:c25a:d00a:d2c3
1972c19:dd:d9:dd:c25:c25a:d00a:d2c4/1282c19:dd:d9:dd:c25:c25a:d00a:d2c4
1982c19:dd:d9:dd:c25:c25a:d00a:d2c5/1282c19:dd:d9:dd:c25:c25a:d00a:d2c5
1992c19:dd:d9:dd:c25:c25a:d00a:d2c6/1282c19:dd:d9:dd:c25:c25a:d00a:d2c6
2002c19:dd:d9:dd:c25:c25a:d00a:d2c7/1282c19:dd:d9:dd:c25:c25a:d00a:d2c7
2012c19:dd:d9:dd:c25:c25a:d00a:d2c8/1282c19:dd:d9:dd:c25:c25a:d00a:d2c8
2022c19:dd:d9:dd:c25:c25a:d00a:d2c9/1282c19:dd:d9:dd:c25:c25a:d00a:d2c9
2032c19:dd:d9:dd:c25:c25a:d00a:d2ca/1282c19:dd:d9:dd:c25:c25a:d00a:d2ca
2042c19:dd:d9:dd:c25:c25a:d00a:d2cb/1282c19:dd:d9:dd:c25:c25a:d00a:d2cb
2052c19:dd:d9:dd:c25:c25a:d00a:d2cc/1282c19:dd:d9:dd:c25:c25a:d00a:d2cc
2062c19:dd:d9:dd:c25:c25a:d00a:d2cd/1282c19:dd:d9:dd:c25:c25a:d00a:d2cd
2072c19:dd:d9:dd:c25:c25a:d00a:d2ce/1282c19:dd:d9:dd:c25:c25a:d00a:d2ce
2082c19:dd:d9:dd:c25:c25a:d00a:d2cf/1282c19:dd:d9:dd:c25:c25a:d00a:d2cf
2092c19:dd:d9:dd:c25:c25a:d00a:d2d0/1282c19:dd:d9:dd:c25:c25a:d00a:d2d0
2102c19:dd:d9:dd:c25:c25a:d00a:d2d1/1282c19:dd:d9:dd:c25:c25a:d00a:d2d1
2112c19:dd:d9:dd:c25:c25a:d00a:d2d2/1282c19:dd:d9:dd:c25:c25a:d00a:d2d2
2122c19:dd:d9:dd:c25:c25a:d00a:d2d3/1282c19:dd:d9:dd:c25:c25a:d00a:d2d3
2132c19:dd:d9:dd:c25:c25a:d00a:d2d4/1282c19:dd:d9:dd:c25:c25a:d00a:d2d4
2142c19:dd:d9:dd:c25:c25a:d00a:d2d5/1282c19:dd:d9:dd:c25:c25a:d00a:d2d5
2152c19:dd:d9:dd:c25:c25a:d00a:d2d6/1282c19:dd:d9:dd:c25:c25a:d00a:d2d6
2162c19:dd:d9:dd:c25:c25a:d00a:d2d7/1282c19:dd:d9:dd:c25:c25a:d00a:d2d7
2172c19:dd:d9:dd:c25:c25a:d00a:d2d8/1282c19:dd:d9:dd:c25:c25a:d00a:d2d8
2182c19:dd:d9:dd:c25:c25a:d00a:d2d9/1282c19:dd:d9:dd:c25:c25a:d00a:d2d9
2192c19:dd:d9:dd:c25:c25a:d00a:d2da/1282c19:dd:d9:dd:c25:c25a:d00a:d2da
2202c19:dd:d9:dd:c25:c25a:d00a:d2db/1282c19:dd:d9:dd:c25:c25a:d00a:d2db
2212c19:dd:d9:dd:c25:c25a:d00a:d2dc/1282c19:dd:d9:dd:c25:c25a:d00a:d2dc
2222c19:dd:d9:dd:c25:c25a:d00a:d2dd/1282c19:dd:d9:dd:c25:c25a:d00a:d2dd
2232c19:dd:d9:dd:c25:c25a:d00a:d2de/1282c19:dd:d9:dd:c25:c25a:d00a:d2de
2242c19:dd:d9:dd:c25:c25a:d00a:d2df/1282c19:dd:d9:dd:c25:c25a:d00a:d2df
2252c19:dd:d9:dd:c25:c25a:d00a:d2e0/1282c19:dd:d9:dd:c25:c25a:d00a:d2e0
2262c19:dd:d9:dd:c25:c25a:d00a:d2e1/1282c19:dd:d9:dd:c25:c25a:d00a:d2e1
2272c19:dd:d9:dd:c25:c25a:d00a:d2e2/1282c19:dd:d9:dd:c25:c25a:d00a:d2e2
2282c19:dd:d9:dd:c25:c25a:d00a:d2e3/1282c19:dd:d9:dd:c25:c25a:d00a:d2e3
2292c19:dd:d9:dd:c25:c25a:d00a:d2e4/1282c19:dd:d9:dd:c25:c25a:d00a:d2e4
2302c19:dd:d9:dd:c25:c25a:d00a:d2e5/1282c19:dd:d9:dd:c25:c25a:d00a:d2e5
2312c19:dd:d9:dd:c25:c25a:d00a:d2e6/1282c19:dd:d9:dd:c25:c25a:d00a:d2e6
2322c19:dd:d9:dd:c25:c25a:d00a:d2e7/1282c19:dd:d9:dd:c25:c25a:d00a:d2e7
2332c19:dd:d9:dd:c25:c25a:d00a:d2e8/1282c19:dd:d9:dd:c25:c25a:d00a:d2e8
2342c19:dd:d9:dd:c25:c25a:d00a:d2e9/1282c19:dd:d9:dd:c25:c25a:d00a:d2e9
2352c19:dd:d9:dd:c25:c25a:d00a:d2ea/1282c19:dd:d9:dd:c25:c25a:d00a:d2ea
2362c19:dd:d9:dd:c25:c25a:d00a:d2eb/1282c19:dd:d9:dd:c25:c25a:d00a:d2eb
2372c19:dd:d9:dd:c25:c25a:d00a:d2ec/1282c19:dd:d9:dd:c25:c25a:d00a:d2ec
2382c19:dd:d9:dd:c25:c25a:d00a:d2ed/1282c19:dd:d9:dd:c25:c25a:d00a:d2ed
2392c19:dd:d9:dd:c25:c25a:d00a:d2ee/1282c19:dd:d9:dd:c25:c25a:d00a:d2ee
2402c19:dd:d9:dd:c25:c25a:d00a:d2ef/1282c19:dd:d9:dd:c25:c25a:d00a:d2ef
2412c19:dd:d9:dd:c25:c25a:d00a:d2f0/1282c19:dd:d9:dd:c25:c25a:d00a:d2f0
2422c19:dd:d9:dd:c25:c25a:d00a:d2f1/1282c19:dd:d9:dd:c25:c25a:d00a:d2f1
2432c19:dd:d9:dd:c25:c25a:d00a:d2f2/1282c19:dd:d9:dd:c25:c25a:d00a:d2f2
2442c19:dd:d9:dd:c25:c25a:d00a:d2f3/1282c19:dd:d9:dd:c25:c25a:d00a:d2f3
2452c19:dd:d9:dd:c25:c25a:d00a:d2f4/1282c19:dd:d9:dd:c25:c25a:d00a:d2f4
2462c19:dd:d9:dd:c25:c25a:d00a:d2f5/1282c19:dd:d9:dd:c25:c25a:d00a:d2f5
2472c19:dd:d9:dd:c25:c25a:d00a:d2f6/1282c19:dd:d9:dd:c25:c25a:d00a:d2f6
2482c19:dd:d9:dd:c25:c25a:d00a:d2f7/1282c19:dd:d9:dd:c25:c25a:d00a:d2f7
2492c19:dd:d9:dd:c25:c25a:d00a:d2f8/1282c19:dd:d9:dd:c25:c25a:d00a:d2f8
2502c19:dd:d9:dd:c25:c25a:d00a:d2f9/1282c19:dd:d9:dd:c25:c25a:d00a:d2f9
2512c19:dd:d9:dd:c25:c25a:d00a:d2fa/1282c19:dd:d9:dd:c25:c25a:d00a:d2fa
2522c19:dd:d9:dd:c25:c25a:d00a:d2fb/1282c19:dd:d9:dd:c25:c25a:d00a:d2fb
2532c19:dd:d9:dd:c25:c25a:d00a:d2fc/1282c19:dd:d9:dd:c25:c25a:d00a:d2fc
2542c19:dd:d9:dd:c25:c25a:d00a:d2fd/1282c19:dd:d9:dd:c25:c25a:d00a:d2fd
2552c19:dd:d9:dd:c25:c25a:d00a:d2fe/1282c19:dd:d9:dd:c25:c25a:d00a:d2fe
2562c19:dd:d9:dd:c25:c25a:d00a:d2ff/1282c19:dd:d9:dd:c25:c25a:d00a:d2ff

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.