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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:b200/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:b200
Last address
2c19:dd:d9:dd:c25:c25a:d00a:b2ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:b200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.b.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:b200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:b200/1282c19:dd:d9:dd:c25:c25a:d00a:b200
22c19:dd:d9:dd:c25:c25a:d00a:b201/1282c19:dd:d9:dd:c25:c25a:d00a:b201
32c19:dd:d9:dd:c25:c25a:d00a:b202/1282c19:dd:d9:dd:c25:c25a:d00a:b202
42c19:dd:d9:dd:c25:c25a:d00a:b203/1282c19:dd:d9:dd:c25:c25a:d00a:b203
52c19:dd:d9:dd:c25:c25a:d00a:b204/1282c19:dd:d9:dd:c25:c25a:d00a:b204
62c19:dd:d9:dd:c25:c25a:d00a:b205/1282c19:dd:d9:dd:c25:c25a:d00a:b205
72c19:dd:d9:dd:c25:c25a:d00a:b206/1282c19:dd:d9:dd:c25:c25a:d00a:b206
82c19:dd:d9:dd:c25:c25a:d00a:b207/1282c19:dd:d9:dd:c25:c25a:d00a:b207
92c19:dd:d9:dd:c25:c25a:d00a:b208/1282c19:dd:d9:dd:c25:c25a:d00a:b208
102c19:dd:d9:dd:c25:c25a:d00a:b209/1282c19:dd:d9:dd:c25:c25a:d00a:b209
112c19:dd:d9:dd:c25:c25a:d00a:b20a/1282c19:dd:d9:dd:c25:c25a:d00a:b20a
122c19:dd:d9:dd:c25:c25a:d00a:b20b/1282c19:dd:d9:dd:c25:c25a:d00a:b20b
132c19:dd:d9:dd:c25:c25a:d00a:b20c/1282c19:dd:d9:dd:c25:c25a:d00a:b20c
142c19:dd:d9:dd:c25:c25a:d00a:b20d/1282c19:dd:d9:dd:c25:c25a:d00a:b20d
152c19:dd:d9:dd:c25:c25a:d00a:b20e/1282c19:dd:d9:dd:c25:c25a:d00a:b20e
162c19:dd:d9:dd:c25:c25a:d00a:b20f/1282c19:dd:d9:dd:c25:c25a:d00a:b20f
172c19:dd:d9:dd:c25:c25a:d00a:b210/1282c19:dd:d9:dd:c25:c25a:d00a:b210
182c19:dd:d9:dd:c25:c25a:d00a:b211/1282c19:dd:d9:dd:c25:c25a:d00a:b211
192c19:dd:d9:dd:c25:c25a:d00a:b212/1282c19:dd:d9:dd:c25:c25a:d00a:b212
202c19:dd:d9:dd:c25:c25a:d00a:b213/1282c19:dd:d9:dd:c25:c25a:d00a:b213
212c19:dd:d9:dd:c25:c25a:d00a:b214/1282c19:dd:d9:dd:c25:c25a:d00a:b214
222c19:dd:d9:dd:c25:c25a:d00a:b215/1282c19:dd:d9:dd:c25:c25a:d00a:b215
232c19:dd:d9:dd:c25:c25a:d00a:b216/1282c19:dd:d9:dd:c25:c25a:d00a:b216
242c19:dd:d9:dd:c25:c25a:d00a:b217/1282c19:dd:d9:dd:c25:c25a:d00a:b217
252c19:dd:d9:dd:c25:c25a:d00a:b218/1282c19:dd:d9:dd:c25:c25a:d00a:b218
262c19:dd:d9:dd:c25:c25a:d00a:b219/1282c19:dd:d9:dd:c25:c25a:d00a:b219
272c19:dd:d9:dd:c25:c25a:d00a:b21a/1282c19:dd:d9:dd:c25:c25a:d00a:b21a
282c19:dd:d9:dd:c25:c25a:d00a:b21b/1282c19:dd:d9:dd:c25:c25a:d00a:b21b
292c19:dd:d9:dd:c25:c25a:d00a:b21c/1282c19:dd:d9:dd:c25:c25a:d00a:b21c
302c19:dd:d9:dd:c25:c25a:d00a:b21d/1282c19:dd:d9:dd:c25:c25a:d00a:b21d
312c19:dd:d9:dd:c25:c25a:d00a:b21e/1282c19:dd:d9:dd:c25:c25a:d00a:b21e
322c19:dd:d9:dd:c25:c25a:d00a:b21f/1282c19:dd:d9:dd:c25:c25a:d00a:b21f
332c19:dd:d9:dd:c25:c25a:d00a:b220/1282c19:dd:d9:dd:c25:c25a:d00a:b220
342c19:dd:d9:dd:c25:c25a:d00a:b221/1282c19:dd:d9:dd:c25:c25a:d00a:b221
352c19:dd:d9:dd:c25:c25a:d00a:b222/1282c19:dd:d9:dd:c25:c25a:d00a:b222
362c19:dd:d9:dd:c25:c25a:d00a:b223/1282c19:dd:d9:dd:c25:c25a:d00a:b223
372c19:dd:d9:dd:c25:c25a:d00a:b224/1282c19:dd:d9:dd:c25:c25a:d00a:b224
382c19:dd:d9:dd:c25:c25a:d00a:b225/1282c19:dd:d9:dd:c25:c25a:d00a:b225
392c19:dd:d9:dd:c25:c25a:d00a:b226/1282c19:dd:d9:dd:c25:c25a:d00a:b226
402c19:dd:d9:dd:c25:c25a:d00a:b227/1282c19:dd:d9:dd:c25:c25a:d00a:b227
412c19:dd:d9:dd:c25:c25a:d00a:b228/1282c19:dd:d9:dd:c25:c25a:d00a:b228
422c19:dd:d9:dd:c25:c25a:d00a:b229/1282c19:dd:d9:dd:c25:c25a:d00a:b229
432c19:dd:d9:dd:c25:c25a:d00a:b22a/1282c19:dd:d9:dd:c25:c25a:d00a:b22a
442c19:dd:d9:dd:c25:c25a:d00a:b22b/1282c19:dd:d9:dd:c25:c25a:d00a:b22b
452c19:dd:d9:dd:c25:c25a:d00a:b22c/1282c19:dd:d9:dd:c25:c25a:d00a:b22c
462c19:dd:d9:dd:c25:c25a:d00a:b22d/1282c19:dd:d9:dd:c25:c25a:d00a:b22d
472c19:dd:d9:dd:c25:c25a:d00a:b22e/1282c19:dd:d9:dd:c25:c25a:d00a:b22e
482c19:dd:d9:dd:c25:c25a:d00a:b22f/1282c19:dd:d9:dd:c25:c25a:d00a:b22f
492c19:dd:d9:dd:c25:c25a:d00a:b230/1282c19:dd:d9:dd:c25:c25a:d00a:b230
502c19:dd:d9:dd:c25:c25a:d00a:b231/1282c19:dd:d9:dd:c25:c25a:d00a:b231
512c19:dd:d9:dd:c25:c25a:d00a:b232/1282c19:dd:d9:dd:c25:c25a:d00a:b232
522c19:dd:d9:dd:c25:c25a:d00a:b233/1282c19:dd:d9:dd:c25:c25a:d00a:b233
532c19:dd:d9:dd:c25:c25a:d00a:b234/1282c19:dd:d9:dd:c25:c25a:d00a:b234
542c19:dd:d9:dd:c25:c25a:d00a:b235/1282c19:dd:d9:dd:c25:c25a:d00a:b235
552c19:dd:d9:dd:c25:c25a:d00a:b236/1282c19:dd:d9:dd:c25:c25a:d00a:b236
562c19:dd:d9:dd:c25:c25a:d00a:b237/1282c19:dd:d9:dd:c25:c25a:d00a:b237
572c19:dd:d9:dd:c25:c25a:d00a:b238/1282c19:dd:d9:dd:c25:c25a:d00a:b238
582c19:dd:d9:dd:c25:c25a:d00a:b239/1282c19:dd:d9:dd:c25:c25a:d00a:b239
592c19:dd:d9:dd:c25:c25a:d00a:b23a/1282c19:dd:d9:dd:c25:c25a:d00a:b23a
602c19:dd:d9:dd:c25:c25a:d00a:b23b/1282c19:dd:d9:dd:c25:c25a:d00a:b23b
612c19:dd:d9:dd:c25:c25a:d00a:b23c/1282c19:dd:d9:dd:c25:c25a:d00a:b23c
622c19:dd:d9:dd:c25:c25a:d00a:b23d/1282c19:dd:d9:dd:c25:c25a:d00a:b23d
632c19:dd:d9:dd:c25:c25a:d00a:b23e/1282c19:dd:d9:dd:c25:c25a:d00a:b23e
642c19:dd:d9:dd:c25:c25a:d00a:b23f/1282c19:dd:d9:dd:c25:c25a:d00a:b23f
652c19:dd:d9:dd:c25:c25a:d00a:b240/1282c19:dd:d9:dd:c25:c25a:d00a:b240
662c19:dd:d9:dd:c25:c25a:d00a:b241/1282c19:dd:d9:dd:c25:c25a:d00a:b241
672c19:dd:d9:dd:c25:c25a:d00a:b242/1282c19:dd:d9:dd:c25:c25a:d00a:b242
682c19:dd:d9:dd:c25:c25a:d00a:b243/1282c19:dd:d9:dd:c25:c25a:d00a:b243
692c19:dd:d9:dd:c25:c25a:d00a:b244/1282c19:dd:d9:dd:c25:c25a:d00a:b244
702c19:dd:d9:dd:c25:c25a:d00a:b245/1282c19:dd:d9:dd:c25:c25a:d00a:b245
712c19:dd:d9:dd:c25:c25a:d00a:b246/1282c19:dd:d9:dd:c25:c25a:d00a:b246
722c19:dd:d9:dd:c25:c25a:d00a:b247/1282c19:dd:d9:dd:c25:c25a:d00a:b247
732c19:dd:d9:dd:c25:c25a:d00a:b248/1282c19:dd:d9:dd:c25:c25a:d00a:b248
742c19:dd:d9:dd:c25:c25a:d00a:b249/1282c19:dd:d9:dd:c25:c25a:d00a:b249
752c19:dd:d9:dd:c25:c25a:d00a:b24a/1282c19:dd:d9:dd:c25:c25a:d00a:b24a
762c19:dd:d9:dd:c25:c25a:d00a:b24b/1282c19:dd:d9:dd:c25:c25a:d00a:b24b
772c19:dd:d9:dd:c25:c25a:d00a:b24c/1282c19:dd:d9:dd:c25:c25a:d00a:b24c
782c19:dd:d9:dd:c25:c25a:d00a:b24d/1282c19:dd:d9:dd:c25:c25a:d00a:b24d
792c19:dd:d9:dd:c25:c25a:d00a:b24e/1282c19:dd:d9:dd:c25:c25a:d00a:b24e
802c19:dd:d9:dd:c25:c25a:d00a:b24f/1282c19:dd:d9:dd:c25:c25a:d00a:b24f
812c19:dd:d9:dd:c25:c25a:d00a:b250/1282c19:dd:d9:dd:c25:c25a:d00a:b250
822c19:dd:d9:dd:c25:c25a:d00a:b251/1282c19:dd:d9:dd:c25:c25a:d00a:b251
832c19:dd:d9:dd:c25:c25a:d00a:b252/1282c19:dd:d9:dd:c25:c25a:d00a:b252
842c19:dd:d9:dd:c25:c25a:d00a:b253/1282c19:dd:d9:dd:c25:c25a:d00a:b253
852c19:dd:d9:dd:c25:c25a:d00a:b254/1282c19:dd:d9:dd:c25:c25a:d00a:b254
862c19:dd:d9:dd:c25:c25a:d00a:b255/1282c19:dd:d9:dd:c25:c25a:d00a:b255
872c19:dd:d9:dd:c25:c25a:d00a:b256/1282c19:dd:d9:dd:c25:c25a:d00a:b256
882c19:dd:d9:dd:c25:c25a:d00a:b257/1282c19:dd:d9:dd:c25:c25a:d00a:b257
892c19:dd:d9:dd:c25:c25a:d00a:b258/1282c19:dd:d9:dd:c25:c25a:d00a:b258
902c19:dd:d9:dd:c25:c25a:d00a:b259/1282c19:dd:d9:dd:c25:c25a:d00a:b259
912c19:dd:d9:dd:c25:c25a:d00a:b25a/1282c19:dd:d9:dd:c25:c25a:d00a:b25a
922c19:dd:d9:dd:c25:c25a:d00a:b25b/1282c19:dd:d9:dd:c25:c25a:d00a:b25b
932c19:dd:d9:dd:c25:c25a:d00a:b25c/1282c19:dd:d9:dd:c25:c25a:d00a:b25c
942c19:dd:d9:dd:c25:c25a:d00a:b25d/1282c19:dd:d9:dd:c25:c25a:d00a:b25d
952c19:dd:d9:dd:c25:c25a:d00a:b25e/1282c19:dd:d9:dd:c25:c25a:d00a:b25e
962c19:dd:d9:dd:c25:c25a:d00a:b25f/1282c19:dd:d9:dd:c25:c25a:d00a:b25f
972c19:dd:d9:dd:c25:c25a:d00a:b260/1282c19:dd:d9:dd:c25:c25a:d00a:b260
982c19:dd:d9:dd:c25:c25a:d00a:b261/1282c19:dd:d9:dd:c25:c25a:d00a:b261
992c19:dd:d9:dd:c25:c25a:d00a:b262/1282c19:dd:d9:dd:c25:c25a:d00a:b262
1002c19:dd:d9:dd:c25:c25a:d00a:b263/1282c19:dd:d9:dd:c25:c25a:d00a:b263
1012c19:dd:d9:dd:c25:c25a:d00a:b264/1282c19:dd:d9:dd:c25:c25a:d00a:b264
1022c19:dd:d9:dd:c25:c25a:d00a:b265/1282c19:dd:d9:dd:c25:c25a:d00a:b265
1032c19:dd:d9:dd:c25:c25a:d00a:b266/1282c19:dd:d9:dd:c25:c25a:d00a:b266
1042c19:dd:d9:dd:c25:c25a:d00a:b267/1282c19:dd:d9:dd:c25:c25a:d00a:b267
1052c19:dd:d9:dd:c25:c25a:d00a:b268/1282c19:dd:d9:dd:c25:c25a:d00a:b268
1062c19:dd:d9:dd:c25:c25a:d00a:b269/1282c19:dd:d9:dd:c25:c25a:d00a:b269
1072c19:dd:d9:dd:c25:c25a:d00a:b26a/1282c19:dd:d9:dd:c25:c25a:d00a:b26a
1082c19:dd:d9:dd:c25:c25a:d00a:b26b/1282c19:dd:d9:dd:c25:c25a:d00a:b26b
1092c19:dd:d9:dd:c25:c25a:d00a:b26c/1282c19:dd:d9:dd:c25:c25a:d00a:b26c
1102c19:dd:d9:dd:c25:c25a:d00a:b26d/1282c19:dd:d9:dd:c25:c25a:d00a:b26d
1112c19:dd:d9:dd:c25:c25a:d00a:b26e/1282c19:dd:d9:dd:c25:c25a:d00a:b26e
1122c19:dd:d9:dd:c25:c25a:d00a:b26f/1282c19:dd:d9:dd:c25:c25a:d00a:b26f
1132c19:dd:d9:dd:c25:c25a:d00a:b270/1282c19:dd:d9:dd:c25:c25a:d00a:b270
1142c19:dd:d9:dd:c25:c25a:d00a:b271/1282c19:dd:d9:dd:c25:c25a:d00a:b271
1152c19:dd:d9:dd:c25:c25a:d00a:b272/1282c19:dd:d9:dd:c25:c25a:d00a:b272
1162c19:dd:d9:dd:c25:c25a:d00a:b273/1282c19:dd:d9:dd:c25:c25a:d00a:b273
1172c19:dd:d9:dd:c25:c25a:d00a:b274/1282c19:dd:d9:dd:c25:c25a:d00a:b274
1182c19:dd:d9:dd:c25:c25a:d00a:b275/1282c19:dd:d9:dd:c25:c25a:d00a:b275
1192c19:dd:d9:dd:c25:c25a:d00a:b276/1282c19:dd:d9:dd:c25:c25a:d00a:b276
1202c19:dd:d9:dd:c25:c25a:d00a:b277/1282c19:dd:d9:dd:c25:c25a:d00a:b277
1212c19:dd:d9:dd:c25:c25a:d00a:b278/1282c19:dd:d9:dd:c25:c25a:d00a:b278
1222c19:dd:d9:dd:c25:c25a:d00a:b279/1282c19:dd:d9:dd:c25:c25a:d00a:b279
1232c19:dd:d9:dd:c25:c25a:d00a:b27a/1282c19:dd:d9:dd:c25:c25a:d00a:b27a
1242c19:dd:d9:dd:c25:c25a:d00a:b27b/1282c19:dd:d9:dd:c25:c25a:d00a:b27b
1252c19:dd:d9:dd:c25:c25a:d00a:b27c/1282c19:dd:d9:dd:c25:c25a:d00a:b27c
1262c19:dd:d9:dd:c25:c25a:d00a:b27d/1282c19:dd:d9:dd:c25:c25a:d00a:b27d
1272c19:dd:d9:dd:c25:c25a:d00a:b27e/1282c19:dd:d9:dd:c25:c25a:d00a:b27e
1282c19:dd:d9:dd:c25:c25a:d00a:b27f/1282c19:dd:d9:dd:c25:c25a:d00a:b27f
1292c19:dd:d9:dd:c25:c25a:d00a:b280/1282c19:dd:d9:dd:c25:c25a:d00a:b280
1302c19:dd:d9:dd:c25:c25a:d00a:b281/1282c19:dd:d9:dd:c25:c25a:d00a:b281
1312c19:dd:d9:dd:c25:c25a:d00a:b282/1282c19:dd:d9:dd:c25:c25a:d00a:b282
1322c19:dd:d9:dd:c25:c25a:d00a:b283/1282c19:dd:d9:dd:c25:c25a:d00a:b283
1332c19:dd:d9:dd:c25:c25a:d00a:b284/1282c19:dd:d9:dd:c25:c25a:d00a:b284
1342c19:dd:d9:dd:c25:c25a:d00a:b285/1282c19:dd:d9:dd:c25:c25a:d00a:b285
1352c19:dd:d9:dd:c25:c25a:d00a:b286/1282c19:dd:d9:dd:c25:c25a:d00a:b286
1362c19:dd:d9:dd:c25:c25a:d00a:b287/1282c19:dd:d9:dd:c25:c25a:d00a:b287
1372c19:dd:d9:dd:c25:c25a:d00a:b288/1282c19:dd:d9:dd:c25:c25a:d00a:b288
1382c19:dd:d9:dd:c25:c25a:d00a:b289/1282c19:dd:d9:dd:c25:c25a:d00a:b289
1392c19:dd:d9:dd:c25:c25a:d00a:b28a/1282c19:dd:d9:dd:c25:c25a:d00a:b28a
1402c19:dd:d9:dd:c25:c25a:d00a:b28b/1282c19:dd:d9:dd:c25:c25a:d00a:b28b
1412c19:dd:d9:dd:c25:c25a:d00a:b28c/1282c19:dd:d9:dd:c25:c25a:d00a:b28c
1422c19:dd:d9:dd:c25:c25a:d00a:b28d/1282c19:dd:d9:dd:c25:c25a:d00a:b28d
1432c19:dd:d9:dd:c25:c25a:d00a:b28e/1282c19:dd:d9:dd:c25:c25a:d00a:b28e
1442c19:dd:d9:dd:c25:c25a:d00a:b28f/1282c19:dd:d9:dd:c25:c25a:d00a:b28f
1452c19:dd:d9:dd:c25:c25a:d00a:b290/1282c19:dd:d9:dd:c25:c25a:d00a:b290
1462c19:dd:d9:dd:c25:c25a:d00a:b291/1282c19:dd:d9:dd:c25:c25a:d00a:b291
1472c19:dd:d9:dd:c25:c25a:d00a:b292/1282c19:dd:d9:dd:c25:c25a:d00a:b292
1482c19:dd:d9:dd:c25:c25a:d00a:b293/1282c19:dd:d9:dd:c25:c25a:d00a:b293
1492c19:dd:d9:dd:c25:c25a:d00a:b294/1282c19:dd:d9:dd:c25:c25a:d00a:b294
1502c19:dd:d9:dd:c25:c25a:d00a:b295/1282c19:dd:d9:dd:c25:c25a:d00a:b295
1512c19:dd:d9:dd:c25:c25a:d00a:b296/1282c19:dd:d9:dd:c25:c25a:d00a:b296
1522c19:dd:d9:dd:c25:c25a:d00a:b297/1282c19:dd:d9:dd:c25:c25a:d00a:b297
1532c19:dd:d9:dd:c25:c25a:d00a:b298/1282c19:dd:d9:dd:c25:c25a:d00a:b298
1542c19:dd:d9:dd:c25:c25a:d00a:b299/1282c19:dd:d9:dd:c25:c25a:d00a:b299
1552c19:dd:d9:dd:c25:c25a:d00a:b29a/1282c19:dd:d9:dd:c25:c25a:d00a:b29a
1562c19:dd:d9:dd:c25:c25a:d00a:b29b/1282c19:dd:d9:dd:c25:c25a:d00a:b29b
1572c19:dd:d9:dd:c25:c25a:d00a:b29c/1282c19:dd:d9:dd:c25:c25a:d00a:b29c
1582c19:dd:d9:dd:c25:c25a:d00a:b29d/1282c19:dd:d9:dd:c25:c25a:d00a:b29d
1592c19:dd:d9:dd:c25:c25a:d00a:b29e/1282c19:dd:d9:dd:c25:c25a:d00a:b29e
1602c19:dd:d9:dd:c25:c25a:d00a:b29f/1282c19:dd:d9:dd:c25:c25a:d00a:b29f
1612c19:dd:d9:dd:c25:c25a:d00a:b2a0/1282c19:dd:d9:dd:c25:c25a:d00a:b2a0
1622c19:dd:d9:dd:c25:c25a:d00a:b2a1/1282c19:dd:d9:dd:c25:c25a:d00a:b2a1
1632c19:dd:d9:dd:c25:c25a:d00a:b2a2/1282c19:dd:d9:dd:c25:c25a:d00a:b2a2
1642c19:dd:d9:dd:c25:c25a:d00a:b2a3/1282c19:dd:d9:dd:c25:c25a:d00a:b2a3
1652c19:dd:d9:dd:c25:c25a:d00a:b2a4/1282c19:dd:d9:dd:c25:c25a:d00a:b2a4
1662c19:dd:d9:dd:c25:c25a:d00a:b2a5/1282c19:dd:d9:dd:c25:c25a:d00a:b2a5
1672c19:dd:d9:dd:c25:c25a:d00a:b2a6/1282c19:dd:d9:dd:c25:c25a:d00a:b2a6
1682c19:dd:d9:dd:c25:c25a:d00a:b2a7/1282c19:dd:d9:dd:c25:c25a:d00a:b2a7
1692c19:dd:d9:dd:c25:c25a:d00a:b2a8/1282c19:dd:d9:dd:c25:c25a:d00a:b2a8
1702c19:dd:d9:dd:c25:c25a:d00a:b2a9/1282c19:dd:d9:dd:c25:c25a:d00a:b2a9
1712c19:dd:d9:dd:c25:c25a:d00a:b2aa/1282c19:dd:d9:dd:c25:c25a:d00a:b2aa
1722c19:dd:d9:dd:c25:c25a:d00a:b2ab/1282c19:dd:d9:dd:c25:c25a:d00a:b2ab
1732c19:dd:d9:dd:c25:c25a:d00a:b2ac/1282c19:dd:d9:dd:c25:c25a:d00a:b2ac
1742c19:dd:d9:dd:c25:c25a:d00a:b2ad/1282c19:dd:d9:dd:c25:c25a:d00a:b2ad
1752c19:dd:d9:dd:c25:c25a:d00a:b2ae/1282c19:dd:d9:dd:c25:c25a:d00a:b2ae
1762c19:dd:d9:dd:c25:c25a:d00a:b2af/1282c19:dd:d9:dd:c25:c25a:d00a:b2af
1772c19:dd:d9:dd:c25:c25a:d00a:b2b0/1282c19:dd:d9:dd:c25:c25a:d00a:b2b0
1782c19:dd:d9:dd:c25:c25a:d00a:b2b1/1282c19:dd:d9:dd:c25:c25a:d00a:b2b1
1792c19:dd:d9:dd:c25:c25a:d00a:b2b2/1282c19:dd:d9:dd:c25:c25a:d00a:b2b2
1802c19:dd:d9:dd:c25:c25a:d00a:b2b3/1282c19:dd:d9:dd:c25:c25a:d00a:b2b3
1812c19:dd:d9:dd:c25:c25a:d00a:b2b4/1282c19:dd:d9:dd:c25:c25a:d00a:b2b4
1822c19:dd:d9:dd:c25:c25a:d00a:b2b5/1282c19:dd:d9:dd:c25:c25a:d00a:b2b5
1832c19:dd:d9:dd:c25:c25a:d00a:b2b6/1282c19:dd:d9:dd:c25:c25a:d00a:b2b6
1842c19:dd:d9:dd:c25:c25a:d00a:b2b7/1282c19:dd:d9:dd:c25:c25a:d00a:b2b7
1852c19:dd:d9:dd:c25:c25a:d00a:b2b8/1282c19:dd:d9:dd:c25:c25a:d00a:b2b8
1862c19:dd:d9:dd:c25:c25a:d00a:b2b9/1282c19:dd:d9:dd:c25:c25a:d00a:b2b9
1872c19:dd:d9:dd:c25:c25a:d00a:b2ba/1282c19:dd:d9:dd:c25:c25a:d00a:b2ba
1882c19:dd:d9:dd:c25:c25a:d00a:b2bb/1282c19:dd:d9:dd:c25:c25a:d00a:b2bb
1892c19:dd:d9:dd:c25:c25a:d00a:b2bc/1282c19:dd:d9:dd:c25:c25a:d00a:b2bc
1902c19:dd:d9:dd:c25:c25a:d00a:b2bd/1282c19:dd:d9:dd:c25:c25a:d00a:b2bd
1912c19:dd:d9:dd:c25:c25a:d00a:b2be/1282c19:dd:d9:dd:c25:c25a:d00a:b2be
1922c19:dd:d9:dd:c25:c25a:d00a:b2bf/1282c19:dd:d9:dd:c25:c25a:d00a:b2bf
1932c19:dd:d9:dd:c25:c25a:d00a:b2c0/1282c19:dd:d9:dd:c25:c25a:d00a:b2c0
1942c19:dd:d9:dd:c25:c25a:d00a:b2c1/1282c19:dd:d9:dd:c25:c25a:d00a:b2c1
1952c19:dd:d9:dd:c25:c25a:d00a:b2c2/1282c19:dd:d9:dd:c25:c25a:d00a:b2c2
1962c19:dd:d9:dd:c25:c25a:d00a:b2c3/1282c19:dd:d9:dd:c25:c25a:d00a:b2c3
1972c19:dd:d9:dd:c25:c25a:d00a:b2c4/1282c19:dd:d9:dd:c25:c25a:d00a:b2c4
1982c19:dd:d9:dd:c25:c25a:d00a:b2c5/1282c19:dd:d9:dd:c25:c25a:d00a:b2c5
1992c19:dd:d9:dd:c25:c25a:d00a:b2c6/1282c19:dd:d9:dd:c25:c25a:d00a:b2c6
2002c19:dd:d9:dd:c25:c25a:d00a:b2c7/1282c19:dd:d9:dd:c25:c25a:d00a:b2c7
2012c19:dd:d9:dd:c25:c25a:d00a:b2c8/1282c19:dd:d9:dd:c25:c25a:d00a:b2c8
2022c19:dd:d9:dd:c25:c25a:d00a:b2c9/1282c19:dd:d9:dd:c25:c25a:d00a:b2c9
2032c19:dd:d9:dd:c25:c25a:d00a:b2ca/1282c19:dd:d9:dd:c25:c25a:d00a:b2ca
2042c19:dd:d9:dd:c25:c25a:d00a:b2cb/1282c19:dd:d9:dd:c25:c25a:d00a:b2cb
2052c19:dd:d9:dd:c25:c25a:d00a:b2cc/1282c19:dd:d9:dd:c25:c25a:d00a:b2cc
2062c19:dd:d9:dd:c25:c25a:d00a:b2cd/1282c19:dd:d9:dd:c25:c25a:d00a:b2cd
2072c19:dd:d9:dd:c25:c25a:d00a:b2ce/1282c19:dd:d9:dd:c25:c25a:d00a:b2ce
2082c19:dd:d9:dd:c25:c25a:d00a:b2cf/1282c19:dd:d9:dd:c25:c25a:d00a:b2cf
2092c19:dd:d9:dd:c25:c25a:d00a:b2d0/1282c19:dd:d9:dd:c25:c25a:d00a:b2d0
2102c19:dd:d9:dd:c25:c25a:d00a:b2d1/1282c19:dd:d9:dd:c25:c25a:d00a:b2d1
2112c19:dd:d9:dd:c25:c25a:d00a:b2d2/1282c19:dd:d9:dd:c25:c25a:d00a:b2d2
2122c19:dd:d9:dd:c25:c25a:d00a:b2d3/1282c19:dd:d9:dd:c25:c25a:d00a:b2d3
2132c19:dd:d9:dd:c25:c25a:d00a:b2d4/1282c19:dd:d9:dd:c25:c25a:d00a:b2d4
2142c19:dd:d9:dd:c25:c25a:d00a:b2d5/1282c19:dd:d9:dd:c25:c25a:d00a:b2d5
2152c19:dd:d9:dd:c25:c25a:d00a:b2d6/1282c19:dd:d9:dd:c25:c25a:d00a:b2d6
2162c19:dd:d9:dd:c25:c25a:d00a:b2d7/1282c19:dd:d9:dd:c25:c25a:d00a:b2d7
2172c19:dd:d9:dd:c25:c25a:d00a:b2d8/1282c19:dd:d9:dd:c25:c25a:d00a:b2d8
2182c19:dd:d9:dd:c25:c25a:d00a:b2d9/1282c19:dd:d9:dd:c25:c25a:d00a:b2d9
2192c19:dd:d9:dd:c25:c25a:d00a:b2da/1282c19:dd:d9:dd:c25:c25a:d00a:b2da
2202c19:dd:d9:dd:c25:c25a:d00a:b2db/1282c19:dd:d9:dd:c25:c25a:d00a:b2db
2212c19:dd:d9:dd:c25:c25a:d00a:b2dc/1282c19:dd:d9:dd:c25:c25a:d00a:b2dc
2222c19:dd:d9:dd:c25:c25a:d00a:b2dd/1282c19:dd:d9:dd:c25:c25a:d00a:b2dd
2232c19:dd:d9:dd:c25:c25a:d00a:b2de/1282c19:dd:d9:dd:c25:c25a:d00a:b2de
2242c19:dd:d9:dd:c25:c25a:d00a:b2df/1282c19:dd:d9:dd:c25:c25a:d00a:b2df
2252c19:dd:d9:dd:c25:c25a:d00a:b2e0/1282c19:dd:d9:dd:c25:c25a:d00a:b2e0
2262c19:dd:d9:dd:c25:c25a:d00a:b2e1/1282c19:dd:d9:dd:c25:c25a:d00a:b2e1
2272c19:dd:d9:dd:c25:c25a:d00a:b2e2/1282c19:dd:d9:dd:c25:c25a:d00a:b2e2
2282c19:dd:d9:dd:c25:c25a:d00a:b2e3/1282c19:dd:d9:dd:c25:c25a:d00a:b2e3
2292c19:dd:d9:dd:c25:c25a:d00a:b2e4/1282c19:dd:d9:dd:c25:c25a:d00a:b2e4
2302c19:dd:d9:dd:c25:c25a:d00a:b2e5/1282c19:dd:d9:dd:c25:c25a:d00a:b2e5
2312c19:dd:d9:dd:c25:c25a:d00a:b2e6/1282c19:dd:d9:dd:c25:c25a:d00a:b2e6
2322c19:dd:d9:dd:c25:c25a:d00a:b2e7/1282c19:dd:d9:dd:c25:c25a:d00a:b2e7
2332c19:dd:d9:dd:c25:c25a:d00a:b2e8/1282c19:dd:d9:dd:c25:c25a:d00a:b2e8
2342c19:dd:d9:dd:c25:c25a:d00a:b2e9/1282c19:dd:d9:dd:c25:c25a:d00a:b2e9
2352c19:dd:d9:dd:c25:c25a:d00a:b2ea/1282c19:dd:d9:dd:c25:c25a:d00a:b2ea
2362c19:dd:d9:dd:c25:c25a:d00a:b2eb/1282c19:dd:d9:dd:c25:c25a:d00a:b2eb
2372c19:dd:d9:dd:c25:c25a:d00a:b2ec/1282c19:dd:d9:dd:c25:c25a:d00a:b2ec
2382c19:dd:d9:dd:c25:c25a:d00a:b2ed/1282c19:dd:d9:dd:c25:c25a:d00a:b2ed
2392c19:dd:d9:dd:c25:c25a:d00a:b2ee/1282c19:dd:d9:dd:c25:c25a:d00a:b2ee
2402c19:dd:d9:dd:c25:c25a:d00a:b2ef/1282c19:dd:d9:dd:c25:c25a:d00a:b2ef
2412c19:dd:d9:dd:c25:c25a:d00a:b2f0/1282c19:dd:d9:dd:c25:c25a:d00a:b2f0
2422c19:dd:d9:dd:c25:c25a:d00a:b2f1/1282c19:dd:d9:dd:c25:c25a:d00a:b2f1
2432c19:dd:d9:dd:c25:c25a:d00a:b2f2/1282c19:dd:d9:dd:c25:c25a:d00a:b2f2
2442c19:dd:d9:dd:c25:c25a:d00a:b2f3/1282c19:dd:d9:dd:c25:c25a:d00a:b2f3
2452c19:dd:d9:dd:c25:c25a:d00a:b2f4/1282c19:dd:d9:dd:c25:c25a:d00a:b2f4
2462c19:dd:d9:dd:c25:c25a:d00a:b2f5/1282c19:dd:d9:dd:c25:c25a:d00a:b2f5
2472c19:dd:d9:dd:c25:c25a:d00a:b2f6/1282c19:dd:d9:dd:c25:c25a:d00a:b2f6
2482c19:dd:d9:dd:c25:c25a:d00a:b2f7/1282c19:dd:d9:dd:c25:c25a:d00a:b2f7
2492c19:dd:d9:dd:c25:c25a:d00a:b2f8/1282c19:dd:d9:dd:c25:c25a:d00a:b2f8
2502c19:dd:d9:dd:c25:c25a:d00a:b2f9/1282c19:dd:d9:dd:c25:c25a:d00a:b2f9
2512c19:dd:d9:dd:c25:c25a:d00a:b2fa/1282c19:dd:d9:dd:c25:c25a:d00a:b2fa
2522c19:dd:d9:dd:c25:c25a:d00a:b2fb/1282c19:dd:d9:dd:c25:c25a:d00a:b2fb
2532c19:dd:d9:dd:c25:c25a:d00a:b2fc/1282c19:dd:d9:dd:c25:c25a:d00a:b2fc
2542c19:dd:d9:dd:c25:c25a:d00a:b2fd/1282c19:dd:d9:dd:c25:c25a:d00a:b2fd
2552c19:dd:d9:dd:c25:c25a:d00a:b2fe/1282c19:dd:d9:dd:c25:c25a:d00a:b2fe
2562c19:dd:d9:dd:c25:c25a:d00a:b2ff/1282c19:dd:d9:dd:c25:c25a:d00a:b2ff

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.