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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:c25:d00a:e200/120
First address
2c19:dd:d9:dd:c25:c25:d00a:e200
Last address
2c19:dd:d9:dd:c25:c25:d00a:e2ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d00a:e200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.e.a.0.0.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:d00a:e200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d00a:e200/1282c19:dd:d9:dd:c25:c25:d00a:e200
22c19:dd:d9:dd:c25:c25:d00a:e201/1282c19:dd:d9:dd:c25:c25:d00a:e201
32c19:dd:d9:dd:c25:c25:d00a:e202/1282c19:dd:d9:dd:c25:c25:d00a:e202
42c19:dd:d9:dd:c25:c25:d00a:e203/1282c19:dd:d9:dd:c25:c25:d00a:e203
52c19:dd:d9:dd:c25:c25:d00a:e204/1282c19:dd:d9:dd:c25:c25:d00a:e204
62c19:dd:d9:dd:c25:c25:d00a:e205/1282c19:dd:d9:dd:c25:c25:d00a:e205
72c19:dd:d9:dd:c25:c25:d00a:e206/1282c19:dd:d9:dd:c25:c25:d00a:e206
82c19:dd:d9:dd:c25:c25:d00a:e207/1282c19:dd:d9:dd:c25:c25:d00a:e207
92c19:dd:d9:dd:c25:c25:d00a:e208/1282c19:dd:d9:dd:c25:c25:d00a:e208
102c19:dd:d9:dd:c25:c25:d00a:e209/1282c19:dd:d9:dd:c25:c25:d00a:e209
112c19:dd:d9:dd:c25:c25:d00a:e20a/1282c19:dd:d9:dd:c25:c25:d00a:e20a
122c19:dd:d9:dd:c25:c25:d00a:e20b/1282c19:dd:d9:dd:c25:c25:d00a:e20b
132c19:dd:d9:dd:c25:c25:d00a:e20c/1282c19:dd:d9:dd:c25:c25:d00a:e20c
142c19:dd:d9:dd:c25:c25:d00a:e20d/1282c19:dd:d9:dd:c25:c25:d00a:e20d
152c19:dd:d9:dd:c25:c25:d00a:e20e/1282c19:dd:d9:dd:c25:c25:d00a:e20e
162c19:dd:d9:dd:c25:c25:d00a:e20f/1282c19:dd:d9:dd:c25:c25:d00a:e20f
172c19:dd:d9:dd:c25:c25:d00a:e210/1282c19:dd:d9:dd:c25:c25:d00a:e210
182c19:dd:d9:dd:c25:c25:d00a:e211/1282c19:dd:d9:dd:c25:c25:d00a:e211
192c19:dd:d9:dd:c25:c25:d00a:e212/1282c19:dd:d9:dd:c25:c25:d00a:e212
202c19:dd:d9:dd:c25:c25:d00a:e213/1282c19:dd:d9:dd:c25:c25:d00a:e213
212c19:dd:d9:dd:c25:c25:d00a:e214/1282c19:dd:d9:dd:c25:c25:d00a:e214
222c19:dd:d9:dd:c25:c25:d00a:e215/1282c19:dd:d9:dd:c25:c25:d00a:e215
232c19:dd:d9:dd:c25:c25:d00a:e216/1282c19:dd:d9:dd:c25:c25:d00a:e216
242c19:dd:d9:dd:c25:c25:d00a:e217/1282c19:dd:d9:dd:c25:c25:d00a:e217
252c19:dd:d9:dd:c25:c25:d00a:e218/1282c19:dd:d9:dd:c25:c25:d00a:e218
262c19:dd:d9:dd:c25:c25:d00a:e219/1282c19:dd:d9:dd:c25:c25:d00a:e219
272c19:dd:d9:dd:c25:c25:d00a:e21a/1282c19:dd:d9:dd:c25:c25:d00a:e21a
282c19:dd:d9:dd:c25:c25:d00a:e21b/1282c19:dd:d9:dd:c25:c25:d00a:e21b
292c19:dd:d9:dd:c25:c25:d00a:e21c/1282c19:dd:d9:dd:c25:c25:d00a:e21c
302c19:dd:d9:dd:c25:c25:d00a:e21d/1282c19:dd:d9:dd:c25:c25:d00a:e21d
312c19:dd:d9:dd:c25:c25:d00a:e21e/1282c19:dd:d9:dd:c25:c25:d00a:e21e
322c19:dd:d9:dd:c25:c25:d00a:e21f/1282c19:dd:d9:dd:c25:c25:d00a:e21f
332c19:dd:d9:dd:c25:c25:d00a:e220/1282c19:dd:d9:dd:c25:c25:d00a:e220
342c19:dd:d9:dd:c25:c25:d00a:e221/1282c19:dd:d9:dd:c25:c25:d00a:e221
352c19:dd:d9:dd:c25:c25:d00a:e222/1282c19:dd:d9:dd:c25:c25:d00a:e222
362c19:dd:d9:dd:c25:c25:d00a:e223/1282c19:dd:d9:dd:c25:c25:d00a:e223
372c19:dd:d9:dd:c25:c25:d00a:e224/1282c19:dd:d9:dd:c25:c25:d00a:e224
382c19:dd:d9:dd:c25:c25:d00a:e225/1282c19:dd:d9:dd:c25:c25:d00a:e225
392c19:dd:d9:dd:c25:c25:d00a:e226/1282c19:dd:d9:dd:c25:c25:d00a:e226
402c19:dd:d9:dd:c25:c25:d00a:e227/1282c19:dd:d9:dd:c25:c25:d00a:e227
412c19:dd:d9:dd:c25:c25:d00a:e228/1282c19:dd:d9:dd:c25:c25:d00a:e228
422c19:dd:d9:dd:c25:c25:d00a:e229/1282c19:dd:d9:dd:c25:c25:d00a:e229
432c19:dd:d9:dd:c25:c25:d00a:e22a/1282c19:dd:d9:dd:c25:c25:d00a:e22a
442c19:dd:d9:dd:c25:c25:d00a:e22b/1282c19:dd:d9:dd:c25:c25:d00a:e22b
452c19:dd:d9:dd:c25:c25:d00a:e22c/1282c19:dd:d9:dd:c25:c25:d00a:e22c
462c19:dd:d9:dd:c25:c25:d00a:e22d/1282c19:dd:d9:dd:c25:c25:d00a:e22d
472c19:dd:d9:dd:c25:c25:d00a:e22e/1282c19:dd:d9:dd:c25:c25:d00a:e22e
482c19:dd:d9:dd:c25:c25:d00a:e22f/1282c19:dd:d9:dd:c25:c25:d00a:e22f
492c19:dd:d9:dd:c25:c25:d00a:e230/1282c19:dd:d9:dd:c25:c25:d00a:e230
502c19:dd:d9:dd:c25:c25:d00a:e231/1282c19:dd:d9:dd:c25:c25:d00a:e231
512c19:dd:d9:dd:c25:c25:d00a:e232/1282c19:dd:d9:dd:c25:c25:d00a:e232
522c19:dd:d9:dd:c25:c25:d00a:e233/1282c19:dd:d9:dd:c25:c25:d00a:e233
532c19:dd:d9:dd:c25:c25:d00a:e234/1282c19:dd:d9:dd:c25:c25:d00a:e234
542c19:dd:d9:dd:c25:c25:d00a:e235/1282c19:dd:d9:dd:c25:c25:d00a:e235
552c19:dd:d9:dd:c25:c25:d00a:e236/1282c19:dd:d9:dd:c25:c25:d00a:e236
562c19:dd:d9:dd:c25:c25:d00a:e237/1282c19:dd:d9:dd:c25:c25:d00a:e237
572c19:dd:d9:dd:c25:c25:d00a:e238/1282c19:dd:d9:dd:c25:c25:d00a:e238
582c19:dd:d9:dd:c25:c25:d00a:e239/1282c19:dd:d9:dd:c25:c25:d00a:e239
592c19:dd:d9:dd:c25:c25:d00a:e23a/1282c19:dd:d9:dd:c25:c25:d00a:e23a
602c19:dd:d9:dd:c25:c25:d00a:e23b/1282c19:dd:d9:dd:c25:c25:d00a:e23b
612c19:dd:d9:dd:c25:c25:d00a:e23c/1282c19:dd:d9:dd:c25:c25:d00a:e23c
622c19:dd:d9:dd:c25:c25:d00a:e23d/1282c19:dd:d9:dd:c25:c25:d00a:e23d
632c19:dd:d9:dd:c25:c25:d00a:e23e/1282c19:dd:d9:dd:c25:c25:d00a:e23e
642c19:dd:d9:dd:c25:c25:d00a:e23f/1282c19:dd:d9:dd:c25:c25:d00a:e23f
652c19:dd:d9:dd:c25:c25:d00a:e240/1282c19:dd:d9:dd:c25:c25:d00a:e240
662c19:dd:d9:dd:c25:c25:d00a:e241/1282c19:dd:d9:dd:c25:c25:d00a:e241
672c19:dd:d9:dd:c25:c25:d00a:e242/1282c19:dd:d9:dd:c25:c25:d00a:e242
682c19:dd:d9:dd:c25:c25:d00a:e243/1282c19:dd:d9:dd:c25:c25:d00a:e243
692c19:dd:d9:dd:c25:c25:d00a:e244/1282c19:dd:d9:dd:c25:c25:d00a:e244
702c19:dd:d9:dd:c25:c25:d00a:e245/1282c19:dd:d9:dd:c25:c25:d00a:e245
712c19:dd:d9:dd:c25:c25:d00a:e246/1282c19:dd:d9:dd:c25:c25:d00a:e246
722c19:dd:d9:dd:c25:c25:d00a:e247/1282c19:dd:d9:dd:c25:c25:d00a:e247
732c19:dd:d9:dd:c25:c25:d00a:e248/1282c19:dd:d9:dd:c25:c25:d00a:e248
742c19:dd:d9:dd:c25:c25:d00a:e249/1282c19:dd:d9:dd:c25:c25:d00a:e249
752c19:dd:d9:dd:c25:c25:d00a:e24a/1282c19:dd:d9:dd:c25:c25:d00a:e24a
762c19:dd:d9:dd:c25:c25:d00a:e24b/1282c19:dd:d9:dd:c25:c25:d00a:e24b
772c19:dd:d9:dd:c25:c25:d00a:e24c/1282c19:dd:d9:dd:c25:c25:d00a:e24c
782c19:dd:d9:dd:c25:c25:d00a:e24d/1282c19:dd:d9:dd:c25:c25:d00a:e24d
792c19:dd:d9:dd:c25:c25:d00a:e24e/1282c19:dd:d9:dd:c25:c25:d00a:e24e
802c19:dd:d9:dd:c25:c25:d00a:e24f/1282c19:dd:d9:dd:c25:c25:d00a:e24f
812c19:dd:d9:dd:c25:c25:d00a:e250/1282c19:dd:d9:dd:c25:c25:d00a:e250
822c19:dd:d9:dd:c25:c25:d00a:e251/1282c19:dd:d9:dd:c25:c25:d00a:e251
832c19:dd:d9:dd:c25:c25:d00a:e252/1282c19:dd:d9:dd:c25:c25:d00a:e252
842c19:dd:d9:dd:c25:c25:d00a:e253/1282c19:dd:d9:dd:c25:c25:d00a:e253
852c19:dd:d9:dd:c25:c25:d00a:e254/1282c19:dd:d9:dd:c25:c25:d00a:e254
862c19:dd:d9:dd:c25:c25:d00a:e255/1282c19:dd:d9:dd:c25:c25:d00a:e255
872c19:dd:d9:dd:c25:c25:d00a:e256/1282c19:dd:d9:dd:c25:c25:d00a:e256
882c19:dd:d9:dd:c25:c25:d00a:e257/1282c19:dd:d9:dd:c25:c25:d00a:e257
892c19:dd:d9:dd:c25:c25:d00a:e258/1282c19:dd:d9:dd:c25:c25:d00a:e258
902c19:dd:d9:dd:c25:c25:d00a:e259/1282c19:dd:d9:dd:c25:c25:d00a:e259
912c19:dd:d9:dd:c25:c25:d00a:e25a/1282c19:dd:d9:dd:c25:c25:d00a:e25a
922c19:dd:d9:dd:c25:c25:d00a:e25b/1282c19:dd:d9:dd:c25:c25:d00a:e25b
932c19:dd:d9:dd:c25:c25:d00a:e25c/1282c19:dd:d9:dd:c25:c25:d00a:e25c
942c19:dd:d9:dd:c25:c25:d00a:e25d/1282c19:dd:d9:dd:c25:c25:d00a:e25d
952c19:dd:d9:dd:c25:c25:d00a:e25e/1282c19:dd:d9:dd:c25:c25:d00a:e25e
962c19:dd:d9:dd:c25:c25:d00a:e25f/1282c19:dd:d9:dd:c25:c25:d00a:e25f
972c19:dd:d9:dd:c25:c25:d00a:e260/1282c19:dd:d9:dd:c25:c25:d00a:e260
982c19:dd:d9:dd:c25:c25:d00a:e261/1282c19:dd:d9:dd:c25:c25:d00a:e261
992c19:dd:d9:dd:c25:c25:d00a:e262/1282c19:dd:d9:dd:c25:c25:d00a:e262
1002c19:dd:d9:dd:c25:c25:d00a:e263/1282c19:dd:d9:dd:c25:c25:d00a:e263
1012c19:dd:d9:dd:c25:c25:d00a:e264/1282c19:dd:d9:dd:c25:c25:d00a:e264
1022c19:dd:d9:dd:c25:c25:d00a:e265/1282c19:dd:d9:dd:c25:c25:d00a:e265
1032c19:dd:d9:dd:c25:c25:d00a:e266/1282c19:dd:d9:dd:c25:c25:d00a:e266
1042c19:dd:d9:dd:c25:c25:d00a:e267/1282c19:dd:d9:dd:c25:c25:d00a:e267
1052c19:dd:d9:dd:c25:c25:d00a:e268/1282c19:dd:d9:dd:c25:c25:d00a:e268
1062c19:dd:d9:dd:c25:c25:d00a:e269/1282c19:dd:d9:dd:c25:c25:d00a:e269
1072c19:dd:d9:dd:c25:c25:d00a:e26a/1282c19:dd:d9:dd:c25:c25:d00a:e26a
1082c19:dd:d9:dd:c25:c25:d00a:e26b/1282c19:dd:d9:dd:c25:c25:d00a:e26b
1092c19:dd:d9:dd:c25:c25:d00a:e26c/1282c19:dd:d9:dd:c25:c25:d00a:e26c
1102c19:dd:d9:dd:c25:c25:d00a:e26d/1282c19:dd:d9:dd:c25:c25:d00a:e26d
1112c19:dd:d9:dd:c25:c25:d00a:e26e/1282c19:dd:d9:dd:c25:c25:d00a:e26e
1122c19:dd:d9:dd:c25:c25:d00a:e26f/1282c19:dd:d9:dd:c25:c25:d00a:e26f
1132c19:dd:d9:dd:c25:c25:d00a:e270/1282c19:dd:d9:dd:c25:c25:d00a:e270
1142c19:dd:d9:dd:c25:c25:d00a:e271/1282c19:dd:d9:dd:c25:c25:d00a:e271
1152c19:dd:d9:dd:c25:c25:d00a:e272/1282c19:dd:d9:dd:c25:c25:d00a:e272
1162c19:dd:d9:dd:c25:c25:d00a:e273/1282c19:dd:d9:dd:c25:c25:d00a:e273
1172c19:dd:d9:dd:c25:c25:d00a:e274/1282c19:dd:d9:dd:c25:c25:d00a:e274
1182c19:dd:d9:dd:c25:c25:d00a:e275/1282c19:dd:d9:dd:c25:c25:d00a:e275
1192c19:dd:d9:dd:c25:c25:d00a:e276/1282c19:dd:d9:dd:c25:c25:d00a:e276
1202c19:dd:d9:dd:c25:c25:d00a:e277/1282c19:dd:d9:dd:c25:c25:d00a:e277
1212c19:dd:d9:dd:c25:c25:d00a:e278/1282c19:dd:d9:dd:c25:c25:d00a:e278
1222c19:dd:d9:dd:c25:c25:d00a:e279/1282c19:dd:d9:dd:c25:c25:d00a:e279
1232c19:dd:d9:dd:c25:c25:d00a:e27a/1282c19:dd:d9:dd:c25:c25:d00a:e27a
1242c19:dd:d9:dd:c25:c25:d00a:e27b/1282c19:dd:d9:dd:c25:c25:d00a:e27b
1252c19:dd:d9:dd:c25:c25:d00a:e27c/1282c19:dd:d9:dd:c25:c25:d00a:e27c
1262c19:dd:d9:dd:c25:c25:d00a:e27d/1282c19:dd:d9:dd:c25:c25:d00a:e27d
1272c19:dd:d9:dd:c25:c25:d00a:e27e/1282c19:dd:d9:dd:c25:c25:d00a:e27e
1282c19:dd:d9:dd:c25:c25:d00a:e27f/1282c19:dd:d9:dd:c25:c25:d00a:e27f
1292c19:dd:d9:dd:c25:c25:d00a:e280/1282c19:dd:d9:dd:c25:c25:d00a:e280
1302c19:dd:d9:dd:c25:c25:d00a:e281/1282c19:dd:d9:dd:c25:c25:d00a:e281
1312c19:dd:d9:dd:c25:c25:d00a:e282/1282c19:dd:d9:dd:c25:c25:d00a:e282
1322c19:dd:d9:dd:c25:c25:d00a:e283/1282c19:dd:d9:dd:c25:c25:d00a:e283
1332c19:dd:d9:dd:c25:c25:d00a:e284/1282c19:dd:d9:dd:c25:c25:d00a:e284
1342c19:dd:d9:dd:c25:c25:d00a:e285/1282c19:dd:d9:dd:c25:c25:d00a:e285
1352c19:dd:d9:dd:c25:c25:d00a:e286/1282c19:dd:d9:dd:c25:c25:d00a:e286
1362c19:dd:d9:dd:c25:c25:d00a:e287/1282c19:dd:d9:dd:c25:c25:d00a:e287
1372c19:dd:d9:dd:c25:c25:d00a:e288/1282c19:dd:d9:dd:c25:c25:d00a:e288
1382c19:dd:d9:dd:c25:c25:d00a:e289/1282c19:dd:d9:dd:c25:c25:d00a:e289
1392c19:dd:d9:dd:c25:c25:d00a:e28a/1282c19:dd:d9:dd:c25:c25:d00a:e28a
1402c19:dd:d9:dd:c25:c25:d00a:e28b/1282c19:dd:d9:dd:c25:c25:d00a:e28b
1412c19:dd:d9:dd:c25:c25:d00a:e28c/1282c19:dd:d9:dd:c25:c25:d00a:e28c
1422c19:dd:d9:dd:c25:c25:d00a:e28d/1282c19:dd:d9:dd:c25:c25:d00a:e28d
1432c19:dd:d9:dd:c25:c25:d00a:e28e/1282c19:dd:d9:dd:c25:c25:d00a:e28e
1442c19:dd:d9:dd:c25:c25:d00a:e28f/1282c19:dd:d9:dd:c25:c25:d00a:e28f
1452c19:dd:d9:dd:c25:c25:d00a:e290/1282c19:dd:d9:dd:c25:c25:d00a:e290
1462c19:dd:d9:dd:c25:c25:d00a:e291/1282c19:dd:d9:dd:c25:c25:d00a:e291
1472c19:dd:d9:dd:c25:c25:d00a:e292/1282c19:dd:d9:dd:c25:c25:d00a:e292
1482c19:dd:d9:dd:c25:c25:d00a:e293/1282c19:dd:d9:dd:c25:c25:d00a:e293
1492c19:dd:d9:dd:c25:c25:d00a:e294/1282c19:dd:d9:dd:c25:c25:d00a:e294
1502c19:dd:d9:dd:c25:c25:d00a:e295/1282c19:dd:d9:dd:c25:c25:d00a:e295
1512c19:dd:d9:dd:c25:c25:d00a:e296/1282c19:dd:d9:dd:c25:c25:d00a:e296
1522c19:dd:d9:dd:c25:c25:d00a:e297/1282c19:dd:d9:dd:c25:c25:d00a:e297
1532c19:dd:d9:dd:c25:c25:d00a:e298/1282c19:dd:d9:dd:c25:c25:d00a:e298
1542c19:dd:d9:dd:c25:c25:d00a:e299/1282c19:dd:d9:dd:c25:c25:d00a:e299
1552c19:dd:d9:dd:c25:c25:d00a:e29a/1282c19:dd:d9:dd:c25:c25:d00a:e29a
1562c19:dd:d9:dd:c25:c25:d00a:e29b/1282c19:dd:d9:dd:c25:c25:d00a:e29b
1572c19:dd:d9:dd:c25:c25:d00a:e29c/1282c19:dd:d9:dd:c25:c25:d00a:e29c
1582c19:dd:d9:dd:c25:c25:d00a:e29d/1282c19:dd:d9:dd:c25:c25:d00a:e29d
1592c19:dd:d9:dd:c25:c25:d00a:e29e/1282c19:dd:d9:dd:c25:c25:d00a:e29e
1602c19:dd:d9:dd:c25:c25:d00a:e29f/1282c19:dd:d9:dd:c25:c25:d00a:e29f
1612c19:dd:d9:dd:c25:c25:d00a:e2a0/1282c19:dd:d9:dd:c25:c25:d00a:e2a0
1622c19:dd:d9:dd:c25:c25:d00a:e2a1/1282c19:dd:d9:dd:c25:c25:d00a:e2a1
1632c19:dd:d9:dd:c25:c25:d00a:e2a2/1282c19:dd:d9:dd:c25:c25:d00a:e2a2
1642c19:dd:d9:dd:c25:c25:d00a:e2a3/1282c19:dd:d9:dd:c25:c25:d00a:e2a3
1652c19:dd:d9:dd:c25:c25:d00a:e2a4/1282c19:dd:d9:dd:c25:c25:d00a:e2a4
1662c19:dd:d9:dd:c25:c25:d00a:e2a5/1282c19:dd:d9:dd:c25:c25:d00a:e2a5
1672c19:dd:d9:dd:c25:c25:d00a:e2a6/1282c19:dd:d9:dd:c25:c25:d00a:e2a6
1682c19:dd:d9:dd:c25:c25:d00a:e2a7/1282c19:dd:d9:dd:c25:c25:d00a:e2a7
1692c19:dd:d9:dd:c25:c25:d00a:e2a8/1282c19:dd:d9:dd:c25:c25:d00a:e2a8
1702c19:dd:d9:dd:c25:c25:d00a:e2a9/1282c19:dd:d9:dd:c25:c25:d00a:e2a9
1712c19:dd:d9:dd:c25:c25:d00a:e2aa/1282c19:dd:d9:dd:c25:c25:d00a:e2aa
1722c19:dd:d9:dd:c25:c25:d00a:e2ab/1282c19:dd:d9:dd:c25:c25:d00a:e2ab
1732c19:dd:d9:dd:c25:c25:d00a:e2ac/1282c19:dd:d9:dd:c25:c25:d00a:e2ac
1742c19:dd:d9:dd:c25:c25:d00a:e2ad/1282c19:dd:d9:dd:c25:c25:d00a:e2ad
1752c19:dd:d9:dd:c25:c25:d00a:e2ae/1282c19:dd:d9:dd:c25:c25:d00a:e2ae
1762c19:dd:d9:dd:c25:c25:d00a:e2af/1282c19:dd:d9:dd:c25:c25:d00a:e2af
1772c19:dd:d9:dd:c25:c25:d00a:e2b0/1282c19:dd:d9:dd:c25:c25:d00a:e2b0
1782c19:dd:d9:dd:c25:c25:d00a:e2b1/1282c19:dd:d9:dd:c25:c25:d00a:e2b1
1792c19:dd:d9:dd:c25:c25:d00a:e2b2/1282c19:dd:d9:dd:c25:c25:d00a:e2b2
1802c19:dd:d9:dd:c25:c25:d00a:e2b3/1282c19:dd:d9:dd:c25:c25:d00a:e2b3
1812c19:dd:d9:dd:c25:c25:d00a:e2b4/1282c19:dd:d9:dd:c25:c25:d00a:e2b4
1822c19:dd:d9:dd:c25:c25:d00a:e2b5/1282c19:dd:d9:dd:c25:c25:d00a:e2b5
1832c19:dd:d9:dd:c25:c25:d00a:e2b6/1282c19:dd:d9:dd:c25:c25:d00a:e2b6
1842c19:dd:d9:dd:c25:c25:d00a:e2b7/1282c19:dd:d9:dd:c25:c25:d00a:e2b7
1852c19:dd:d9:dd:c25:c25:d00a:e2b8/1282c19:dd:d9:dd:c25:c25:d00a:e2b8
1862c19:dd:d9:dd:c25:c25:d00a:e2b9/1282c19:dd:d9:dd:c25:c25:d00a:e2b9
1872c19:dd:d9:dd:c25:c25:d00a:e2ba/1282c19:dd:d9:dd:c25:c25:d00a:e2ba
1882c19:dd:d9:dd:c25:c25:d00a:e2bb/1282c19:dd:d9:dd:c25:c25:d00a:e2bb
1892c19:dd:d9:dd:c25:c25:d00a:e2bc/1282c19:dd:d9:dd:c25:c25:d00a:e2bc
1902c19:dd:d9:dd:c25:c25:d00a:e2bd/1282c19:dd:d9:dd:c25:c25:d00a:e2bd
1912c19:dd:d9:dd:c25:c25:d00a:e2be/1282c19:dd:d9:dd:c25:c25:d00a:e2be
1922c19:dd:d9:dd:c25:c25:d00a:e2bf/1282c19:dd:d9:dd:c25:c25:d00a:e2bf
1932c19:dd:d9:dd:c25:c25:d00a:e2c0/1282c19:dd:d9:dd:c25:c25:d00a:e2c0
1942c19:dd:d9:dd:c25:c25:d00a:e2c1/1282c19:dd:d9:dd:c25:c25:d00a:e2c1
1952c19:dd:d9:dd:c25:c25:d00a:e2c2/1282c19:dd:d9:dd:c25:c25:d00a:e2c2
1962c19:dd:d9:dd:c25:c25:d00a:e2c3/1282c19:dd:d9:dd:c25:c25:d00a:e2c3
1972c19:dd:d9:dd:c25:c25:d00a:e2c4/1282c19:dd:d9:dd:c25:c25:d00a:e2c4
1982c19:dd:d9:dd:c25:c25:d00a:e2c5/1282c19:dd:d9:dd:c25:c25:d00a:e2c5
1992c19:dd:d9:dd:c25:c25:d00a:e2c6/1282c19:dd:d9:dd:c25:c25:d00a:e2c6
2002c19:dd:d9:dd:c25:c25:d00a:e2c7/1282c19:dd:d9:dd:c25:c25:d00a:e2c7
2012c19:dd:d9:dd:c25:c25:d00a:e2c8/1282c19:dd:d9:dd:c25:c25:d00a:e2c8
2022c19:dd:d9:dd:c25:c25:d00a:e2c9/1282c19:dd:d9:dd:c25:c25:d00a:e2c9
2032c19:dd:d9:dd:c25:c25:d00a:e2ca/1282c19:dd:d9:dd:c25:c25:d00a:e2ca
2042c19:dd:d9:dd:c25:c25:d00a:e2cb/1282c19:dd:d9:dd:c25:c25:d00a:e2cb
2052c19:dd:d9:dd:c25:c25:d00a:e2cc/1282c19:dd:d9:dd:c25:c25:d00a:e2cc
2062c19:dd:d9:dd:c25:c25:d00a:e2cd/1282c19:dd:d9:dd:c25:c25:d00a:e2cd
2072c19:dd:d9:dd:c25:c25:d00a:e2ce/1282c19:dd:d9:dd:c25:c25:d00a:e2ce
2082c19:dd:d9:dd:c25:c25:d00a:e2cf/1282c19:dd:d9:dd:c25:c25:d00a:e2cf
2092c19:dd:d9:dd:c25:c25:d00a:e2d0/1282c19:dd:d9:dd:c25:c25:d00a:e2d0
2102c19:dd:d9:dd:c25:c25:d00a:e2d1/1282c19:dd:d9:dd:c25:c25:d00a:e2d1
2112c19:dd:d9:dd:c25:c25:d00a:e2d2/1282c19:dd:d9:dd:c25:c25:d00a:e2d2
2122c19:dd:d9:dd:c25:c25:d00a:e2d3/1282c19:dd:d9:dd:c25:c25:d00a:e2d3
2132c19:dd:d9:dd:c25:c25:d00a:e2d4/1282c19:dd:d9:dd:c25:c25:d00a:e2d4
2142c19:dd:d9:dd:c25:c25:d00a:e2d5/1282c19:dd:d9:dd:c25:c25:d00a:e2d5
2152c19:dd:d9:dd:c25:c25:d00a:e2d6/1282c19:dd:d9:dd:c25:c25:d00a:e2d6
2162c19:dd:d9:dd:c25:c25:d00a:e2d7/1282c19:dd:d9:dd:c25:c25:d00a:e2d7
2172c19:dd:d9:dd:c25:c25:d00a:e2d8/1282c19:dd:d9:dd:c25:c25:d00a:e2d8
2182c19:dd:d9:dd:c25:c25:d00a:e2d9/1282c19:dd:d9:dd:c25:c25:d00a:e2d9
2192c19:dd:d9:dd:c25:c25:d00a:e2da/1282c19:dd:d9:dd:c25:c25:d00a:e2da
2202c19:dd:d9:dd:c25:c25:d00a:e2db/1282c19:dd:d9:dd:c25:c25:d00a:e2db
2212c19:dd:d9:dd:c25:c25:d00a:e2dc/1282c19:dd:d9:dd:c25:c25:d00a:e2dc
2222c19:dd:d9:dd:c25:c25:d00a:e2dd/1282c19:dd:d9:dd:c25:c25:d00a:e2dd
2232c19:dd:d9:dd:c25:c25:d00a:e2de/1282c19:dd:d9:dd:c25:c25:d00a:e2de
2242c19:dd:d9:dd:c25:c25:d00a:e2df/1282c19:dd:d9:dd:c25:c25:d00a:e2df
2252c19:dd:d9:dd:c25:c25:d00a:e2e0/1282c19:dd:d9:dd:c25:c25:d00a:e2e0
2262c19:dd:d9:dd:c25:c25:d00a:e2e1/1282c19:dd:d9:dd:c25:c25:d00a:e2e1
2272c19:dd:d9:dd:c25:c25:d00a:e2e2/1282c19:dd:d9:dd:c25:c25:d00a:e2e2
2282c19:dd:d9:dd:c25:c25:d00a:e2e3/1282c19:dd:d9:dd:c25:c25:d00a:e2e3
2292c19:dd:d9:dd:c25:c25:d00a:e2e4/1282c19:dd:d9:dd:c25:c25:d00a:e2e4
2302c19:dd:d9:dd:c25:c25:d00a:e2e5/1282c19:dd:d9:dd:c25:c25:d00a:e2e5
2312c19:dd:d9:dd:c25:c25:d00a:e2e6/1282c19:dd:d9:dd:c25:c25:d00a:e2e6
2322c19:dd:d9:dd:c25:c25:d00a:e2e7/1282c19:dd:d9:dd:c25:c25:d00a:e2e7
2332c19:dd:d9:dd:c25:c25:d00a:e2e8/1282c19:dd:d9:dd:c25:c25:d00a:e2e8
2342c19:dd:d9:dd:c25:c25:d00a:e2e9/1282c19:dd:d9:dd:c25:c25:d00a:e2e9
2352c19:dd:d9:dd:c25:c25:d00a:e2ea/1282c19:dd:d9:dd:c25:c25:d00a:e2ea
2362c19:dd:d9:dd:c25:c25:d00a:e2eb/1282c19:dd:d9:dd:c25:c25:d00a:e2eb
2372c19:dd:d9:dd:c25:c25:d00a:e2ec/1282c19:dd:d9:dd:c25:c25:d00a:e2ec
2382c19:dd:d9:dd:c25:c25:d00a:e2ed/1282c19:dd:d9:dd:c25:c25:d00a:e2ed
2392c19:dd:d9:dd:c25:c25:d00a:e2ee/1282c19:dd:d9:dd:c25:c25:d00a:e2ee
2402c19:dd:d9:dd:c25:c25:d00a:e2ef/1282c19:dd:d9:dd:c25:c25:d00a:e2ef
2412c19:dd:d9:dd:c25:c25:d00a:e2f0/1282c19:dd:d9:dd:c25:c25:d00a:e2f0
2422c19:dd:d9:dd:c25:c25:d00a:e2f1/1282c19:dd:d9:dd:c25:c25:d00a:e2f1
2432c19:dd:d9:dd:c25:c25:d00a:e2f2/1282c19:dd:d9:dd:c25:c25:d00a:e2f2
2442c19:dd:d9:dd:c25:c25:d00a:e2f3/1282c19:dd:d9:dd:c25:c25:d00a:e2f3
2452c19:dd:d9:dd:c25:c25:d00a:e2f4/1282c19:dd:d9:dd:c25:c25:d00a:e2f4
2462c19:dd:d9:dd:c25:c25:d00a:e2f5/1282c19:dd:d9:dd:c25:c25:d00a:e2f5
2472c19:dd:d9:dd:c25:c25:d00a:e2f6/1282c19:dd:d9:dd:c25:c25:d00a:e2f6
2482c19:dd:d9:dd:c25:c25:d00a:e2f7/1282c19:dd:d9:dd:c25:c25:d00a:e2f7
2492c19:dd:d9:dd:c25:c25:d00a:e2f8/1282c19:dd:d9:dd:c25:c25:d00a:e2f8
2502c19:dd:d9:dd:c25:c25:d00a:e2f9/1282c19:dd:d9:dd:c25:c25:d00a:e2f9
2512c19:dd:d9:dd:c25:c25:d00a:e2fa/1282c19:dd:d9:dd:c25:c25:d00a:e2fa
2522c19:dd:d9:dd:c25:c25:d00a:e2fb/1282c19:dd:d9:dd:c25:c25:d00a:e2fb
2532c19:dd:d9:dd:c25:c25:d00a:e2fc/1282c19:dd:d9:dd:c25:c25:d00a:e2fc
2542c19:dd:d9:dd:c25:c25:d00a:e2fd/1282c19:dd:d9:dd:c25:c25:d00a:e2fd
2552c19:dd:d9:dd:c25:c25:d00a:e2fe/1282c19:dd:d9:dd:c25:c25:d00a:e2fe
2562c19:dd:d9:dd:c25:c25:d00a:e2ff/1282c19:dd:d9:dd:c25:c25:d00a:e2ff

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.