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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:c25b:d00a:f200/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:f200
Last address
2c19:dd:d9:dd:c25:c25b:d00a:f2ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:f200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.f.a.0.0.d.b.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:c25b:d00a:f200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:f200/1282c19:dd:d9:dd:c25:c25b:d00a:f200
22c19:dd:d9:dd:c25:c25b:d00a:f201/1282c19:dd:d9:dd:c25:c25b:d00a:f201
32c19:dd:d9:dd:c25:c25b:d00a:f202/1282c19:dd:d9:dd:c25:c25b:d00a:f202
42c19:dd:d9:dd:c25:c25b:d00a:f203/1282c19:dd:d9:dd:c25:c25b:d00a:f203
52c19:dd:d9:dd:c25:c25b:d00a:f204/1282c19:dd:d9:dd:c25:c25b:d00a:f204
62c19:dd:d9:dd:c25:c25b:d00a:f205/1282c19:dd:d9:dd:c25:c25b:d00a:f205
72c19:dd:d9:dd:c25:c25b:d00a:f206/1282c19:dd:d9:dd:c25:c25b:d00a:f206
82c19:dd:d9:dd:c25:c25b:d00a:f207/1282c19:dd:d9:dd:c25:c25b:d00a:f207
92c19:dd:d9:dd:c25:c25b:d00a:f208/1282c19:dd:d9:dd:c25:c25b:d00a:f208
102c19:dd:d9:dd:c25:c25b:d00a:f209/1282c19:dd:d9:dd:c25:c25b:d00a:f209
112c19:dd:d9:dd:c25:c25b:d00a:f20a/1282c19:dd:d9:dd:c25:c25b:d00a:f20a
122c19:dd:d9:dd:c25:c25b:d00a:f20b/1282c19:dd:d9:dd:c25:c25b:d00a:f20b
132c19:dd:d9:dd:c25:c25b:d00a:f20c/1282c19:dd:d9:dd:c25:c25b:d00a:f20c
142c19:dd:d9:dd:c25:c25b:d00a:f20d/1282c19:dd:d9:dd:c25:c25b:d00a:f20d
152c19:dd:d9:dd:c25:c25b:d00a:f20e/1282c19:dd:d9:dd:c25:c25b:d00a:f20e
162c19:dd:d9:dd:c25:c25b:d00a:f20f/1282c19:dd:d9:dd:c25:c25b:d00a:f20f
172c19:dd:d9:dd:c25:c25b:d00a:f210/1282c19:dd:d9:dd:c25:c25b:d00a:f210
182c19:dd:d9:dd:c25:c25b:d00a:f211/1282c19:dd:d9:dd:c25:c25b:d00a:f211
192c19:dd:d9:dd:c25:c25b:d00a:f212/1282c19:dd:d9:dd:c25:c25b:d00a:f212
202c19:dd:d9:dd:c25:c25b:d00a:f213/1282c19:dd:d9:dd:c25:c25b:d00a:f213
212c19:dd:d9:dd:c25:c25b:d00a:f214/1282c19:dd:d9:dd:c25:c25b:d00a:f214
222c19:dd:d9:dd:c25:c25b:d00a:f215/1282c19:dd:d9:dd:c25:c25b:d00a:f215
232c19:dd:d9:dd:c25:c25b:d00a:f216/1282c19:dd:d9:dd:c25:c25b:d00a:f216
242c19:dd:d9:dd:c25:c25b:d00a:f217/1282c19:dd:d9:dd:c25:c25b:d00a:f217
252c19:dd:d9:dd:c25:c25b:d00a:f218/1282c19:dd:d9:dd:c25:c25b:d00a:f218
262c19:dd:d9:dd:c25:c25b:d00a:f219/1282c19:dd:d9:dd:c25:c25b:d00a:f219
272c19:dd:d9:dd:c25:c25b:d00a:f21a/1282c19:dd:d9:dd:c25:c25b:d00a:f21a
282c19:dd:d9:dd:c25:c25b:d00a:f21b/1282c19:dd:d9:dd:c25:c25b:d00a:f21b
292c19:dd:d9:dd:c25:c25b:d00a:f21c/1282c19:dd:d9:dd:c25:c25b:d00a:f21c
302c19:dd:d9:dd:c25:c25b:d00a:f21d/1282c19:dd:d9:dd:c25:c25b:d00a:f21d
312c19:dd:d9:dd:c25:c25b:d00a:f21e/1282c19:dd:d9:dd:c25:c25b:d00a:f21e
322c19:dd:d9:dd:c25:c25b:d00a:f21f/1282c19:dd:d9:dd:c25:c25b:d00a:f21f
332c19:dd:d9:dd:c25:c25b:d00a:f220/1282c19:dd:d9:dd:c25:c25b:d00a:f220
342c19:dd:d9:dd:c25:c25b:d00a:f221/1282c19:dd:d9:dd:c25:c25b:d00a:f221
352c19:dd:d9:dd:c25:c25b:d00a:f222/1282c19:dd:d9:dd:c25:c25b:d00a:f222
362c19:dd:d9:dd:c25:c25b:d00a:f223/1282c19:dd:d9:dd:c25:c25b:d00a:f223
372c19:dd:d9:dd:c25:c25b:d00a:f224/1282c19:dd:d9:dd:c25:c25b:d00a:f224
382c19:dd:d9:dd:c25:c25b:d00a:f225/1282c19:dd:d9:dd:c25:c25b:d00a:f225
392c19:dd:d9:dd:c25:c25b:d00a:f226/1282c19:dd:d9:dd:c25:c25b:d00a:f226
402c19:dd:d9:dd:c25:c25b:d00a:f227/1282c19:dd:d9:dd:c25:c25b:d00a:f227
412c19:dd:d9:dd:c25:c25b:d00a:f228/1282c19:dd:d9:dd:c25:c25b:d00a:f228
422c19:dd:d9:dd:c25:c25b:d00a:f229/1282c19:dd:d9:dd:c25:c25b:d00a:f229
432c19:dd:d9:dd:c25:c25b:d00a:f22a/1282c19:dd:d9:dd:c25:c25b:d00a:f22a
442c19:dd:d9:dd:c25:c25b:d00a:f22b/1282c19:dd:d9:dd:c25:c25b:d00a:f22b
452c19:dd:d9:dd:c25:c25b:d00a:f22c/1282c19:dd:d9:dd:c25:c25b:d00a:f22c
462c19:dd:d9:dd:c25:c25b:d00a:f22d/1282c19:dd:d9:dd:c25:c25b:d00a:f22d
472c19:dd:d9:dd:c25:c25b:d00a:f22e/1282c19:dd:d9:dd:c25:c25b:d00a:f22e
482c19:dd:d9:dd:c25:c25b:d00a:f22f/1282c19:dd:d9:dd:c25:c25b:d00a:f22f
492c19:dd:d9:dd:c25:c25b:d00a:f230/1282c19:dd:d9:dd:c25:c25b:d00a:f230
502c19:dd:d9:dd:c25:c25b:d00a:f231/1282c19:dd:d9:dd:c25:c25b:d00a:f231
512c19:dd:d9:dd:c25:c25b:d00a:f232/1282c19:dd:d9:dd:c25:c25b:d00a:f232
522c19:dd:d9:dd:c25:c25b:d00a:f233/1282c19:dd:d9:dd:c25:c25b:d00a:f233
532c19:dd:d9:dd:c25:c25b:d00a:f234/1282c19:dd:d9:dd:c25:c25b:d00a:f234
542c19:dd:d9:dd:c25:c25b:d00a:f235/1282c19:dd:d9:dd:c25:c25b:d00a:f235
552c19:dd:d9:dd:c25:c25b:d00a:f236/1282c19:dd:d9:dd:c25:c25b:d00a:f236
562c19:dd:d9:dd:c25:c25b:d00a:f237/1282c19:dd:d9:dd:c25:c25b:d00a:f237
572c19:dd:d9:dd:c25:c25b:d00a:f238/1282c19:dd:d9:dd:c25:c25b:d00a:f238
582c19:dd:d9:dd:c25:c25b:d00a:f239/1282c19:dd:d9:dd:c25:c25b:d00a:f239
592c19:dd:d9:dd:c25:c25b:d00a:f23a/1282c19:dd:d9:dd:c25:c25b:d00a:f23a
602c19:dd:d9:dd:c25:c25b:d00a:f23b/1282c19:dd:d9:dd:c25:c25b:d00a:f23b
612c19:dd:d9:dd:c25:c25b:d00a:f23c/1282c19:dd:d9:dd:c25:c25b:d00a:f23c
622c19:dd:d9:dd:c25:c25b:d00a:f23d/1282c19:dd:d9:dd:c25:c25b:d00a:f23d
632c19:dd:d9:dd:c25:c25b:d00a:f23e/1282c19:dd:d9:dd:c25:c25b:d00a:f23e
642c19:dd:d9:dd:c25:c25b:d00a:f23f/1282c19:dd:d9:dd:c25:c25b:d00a:f23f
652c19:dd:d9:dd:c25:c25b:d00a:f240/1282c19:dd:d9:dd:c25:c25b:d00a:f240
662c19:dd:d9:dd:c25:c25b:d00a:f241/1282c19:dd:d9:dd:c25:c25b:d00a:f241
672c19:dd:d9:dd:c25:c25b:d00a:f242/1282c19:dd:d9:dd:c25:c25b:d00a:f242
682c19:dd:d9:dd:c25:c25b:d00a:f243/1282c19:dd:d9:dd:c25:c25b:d00a:f243
692c19:dd:d9:dd:c25:c25b:d00a:f244/1282c19:dd:d9:dd:c25:c25b:d00a:f244
702c19:dd:d9:dd:c25:c25b:d00a:f245/1282c19:dd:d9:dd:c25:c25b:d00a:f245
712c19:dd:d9:dd:c25:c25b:d00a:f246/1282c19:dd:d9:dd:c25:c25b:d00a:f246
722c19:dd:d9:dd:c25:c25b:d00a:f247/1282c19:dd:d9:dd:c25:c25b:d00a:f247
732c19:dd:d9:dd:c25:c25b:d00a:f248/1282c19:dd:d9:dd:c25:c25b:d00a:f248
742c19:dd:d9:dd:c25:c25b:d00a:f249/1282c19:dd:d9:dd:c25:c25b:d00a:f249
752c19:dd:d9:dd:c25:c25b:d00a:f24a/1282c19:dd:d9:dd:c25:c25b:d00a:f24a
762c19:dd:d9:dd:c25:c25b:d00a:f24b/1282c19:dd:d9:dd:c25:c25b:d00a:f24b
772c19:dd:d9:dd:c25:c25b:d00a:f24c/1282c19:dd:d9:dd:c25:c25b:d00a:f24c
782c19:dd:d9:dd:c25:c25b:d00a:f24d/1282c19:dd:d9:dd:c25:c25b:d00a:f24d
792c19:dd:d9:dd:c25:c25b:d00a:f24e/1282c19:dd:d9:dd:c25:c25b:d00a:f24e
802c19:dd:d9:dd:c25:c25b:d00a:f24f/1282c19:dd:d9:dd:c25:c25b:d00a:f24f
812c19:dd:d9:dd:c25:c25b:d00a:f250/1282c19:dd:d9:dd:c25:c25b:d00a:f250
822c19:dd:d9:dd:c25:c25b:d00a:f251/1282c19:dd:d9:dd:c25:c25b:d00a:f251
832c19:dd:d9:dd:c25:c25b:d00a:f252/1282c19:dd:d9:dd:c25:c25b:d00a:f252
842c19:dd:d9:dd:c25:c25b:d00a:f253/1282c19:dd:d9:dd:c25:c25b:d00a:f253
852c19:dd:d9:dd:c25:c25b:d00a:f254/1282c19:dd:d9:dd:c25:c25b:d00a:f254
862c19:dd:d9:dd:c25:c25b:d00a:f255/1282c19:dd:d9:dd:c25:c25b:d00a:f255
872c19:dd:d9:dd:c25:c25b:d00a:f256/1282c19:dd:d9:dd:c25:c25b:d00a:f256
882c19:dd:d9:dd:c25:c25b:d00a:f257/1282c19:dd:d9:dd:c25:c25b:d00a:f257
892c19:dd:d9:dd:c25:c25b:d00a:f258/1282c19:dd:d9:dd:c25:c25b:d00a:f258
902c19:dd:d9:dd:c25:c25b:d00a:f259/1282c19:dd:d9:dd:c25:c25b:d00a:f259
912c19:dd:d9:dd:c25:c25b:d00a:f25a/1282c19:dd:d9:dd:c25:c25b:d00a:f25a
922c19:dd:d9:dd:c25:c25b:d00a:f25b/1282c19:dd:d9:dd:c25:c25b:d00a:f25b
932c19:dd:d9:dd:c25:c25b:d00a:f25c/1282c19:dd:d9:dd:c25:c25b:d00a:f25c
942c19:dd:d9:dd:c25:c25b:d00a:f25d/1282c19:dd:d9:dd:c25:c25b:d00a:f25d
952c19:dd:d9:dd:c25:c25b:d00a:f25e/1282c19:dd:d9:dd:c25:c25b:d00a:f25e
962c19:dd:d9:dd:c25:c25b:d00a:f25f/1282c19:dd:d9:dd:c25:c25b:d00a:f25f
972c19:dd:d9:dd:c25:c25b:d00a:f260/1282c19:dd:d9:dd:c25:c25b:d00a:f260
982c19:dd:d9:dd:c25:c25b:d00a:f261/1282c19:dd:d9:dd:c25:c25b:d00a:f261
992c19:dd:d9:dd:c25:c25b:d00a:f262/1282c19:dd:d9:dd:c25:c25b:d00a:f262
1002c19:dd:d9:dd:c25:c25b:d00a:f263/1282c19:dd:d9:dd:c25:c25b:d00a:f263
1012c19:dd:d9:dd:c25:c25b:d00a:f264/1282c19:dd:d9:dd:c25:c25b:d00a:f264
1022c19:dd:d9:dd:c25:c25b:d00a:f265/1282c19:dd:d9:dd:c25:c25b:d00a:f265
1032c19:dd:d9:dd:c25:c25b:d00a:f266/1282c19:dd:d9:dd:c25:c25b:d00a:f266
1042c19:dd:d9:dd:c25:c25b:d00a:f267/1282c19:dd:d9:dd:c25:c25b:d00a:f267
1052c19:dd:d9:dd:c25:c25b:d00a:f268/1282c19:dd:d9:dd:c25:c25b:d00a:f268
1062c19:dd:d9:dd:c25:c25b:d00a:f269/1282c19:dd:d9:dd:c25:c25b:d00a:f269
1072c19:dd:d9:dd:c25:c25b:d00a:f26a/1282c19:dd:d9:dd:c25:c25b:d00a:f26a
1082c19:dd:d9:dd:c25:c25b:d00a:f26b/1282c19:dd:d9:dd:c25:c25b:d00a:f26b
1092c19:dd:d9:dd:c25:c25b:d00a:f26c/1282c19:dd:d9:dd:c25:c25b:d00a:f26c
1102c19:dd:d9:dd:c25:c25b:d00a:f26d/1282c19:dd:d9:dd:c25:c25b:d00a:f26d
1112c19:dd:d9:dd:c25:c25b:d00a:f26e/1282c19:dd:d9:dd:c25:c25b:d00a:f26e
1122c19:dd:d9:dd:c25:c25b:d00a:f26f/1282c19:dd:d9:dd:c25:c25b:d00a:f26f
1132c19:dd:d9:dd:c25:c25b:d00a:f270/1282c19:dd:d9:dd:c25:c25b:d00a:f270
1142c19:dd:d9:dd:c25:c25b:d00a:f271/1282c19:dd:d9:dd:c25:c25b:d00a:f271
1152c19:dd:d9:dd:c25:c25b:d00a:f272/1282c19:dd:d9:dd:c25:c25b:d00a:f272
1162c19:dd:d9:dd:c25:c25b:d00a:f273/1282c19:dd:d9:dd:c25:c25b:d00a:f273
1172c19:dd:d9:dd:c25:c25b:d00a:f274/1282c19:dd:d9:dd:c25:c25b:d00a:f274
1182c19:dd:d9:dd:c25:c25b:d00a:f275/1282c19:dd:d9:dd:c25:c25b:d00a:f275
1192c19:dd:d9:dd:c25:c25b:d00a:f276/1282c19:dd:d9:dd:c25:c25b:d00a:f276
1202c19:dd:d9:dd:c25:c25b:d00a:f277/1282c19:dd:d9:dd:c25:c25b:d00a:f277
1212c19:dd:d9:dd:c25:c25b:d00a:f278/1282c19:dd:d9:dd:c25:c25b:d00a:f278
1222c19:dd:d9:dd:c25:c25b:d00a:f279/1282c19:dd:d9:dd:c25:c25b:d00a:f279
1232c19:dd:d9:dd:c25:c25b:d00a:f27a/1282c19:dd:d9:dd:c25:c25b:d00a:f27a
1242c19:dd:d9:dd:c25:c25b:d00a:f27b/1282c19:dd:d9:dd:c25:c25b:d00a:f27b
1252c19:dd:d9:dd:c25:c25b:d00a:f27c/1282c19:dd:d9:dd:c25:c25b:d00a:f27c
1262c19:dd:d9:dd:c25:c25b:d00a:f27d/1282c19:dd:d9:dd:c25:c25b:d00a:f27d
1272c19:dd:d9:dd:c25:c25b:d00a:f27e/1282c19:dd:d9:dd:c25:c25b:d00a:f27e
1282c19:dd:d9:dd:c25:c25b:d00a:f27f/1282c19:dd:d9:dd:c25:c25b:d00a:f27f
1292c19:dd:d9:dd:c25:c25b:d00a:f280/1282c19:dd:d9:dd:c25:c25b:d00a:f280
1302c19:dd:d9:dd:c25:c25b:d00a:f281/1282c19:dd:d9:dd:c25:c25b:d00a:f281
1312c19:dd:d9:dd:c25:c25b:d00a:f282/1282c19:dd:d9:dd:c25:c25b:d00a:f282
1322c19:dd:d9:dd:c25:c25b:d00a:f283/1282c19:dd:d9:dd:c25:c25b:d00a:f283
1332c19:dd:d9:dd:c25:c25b:d00a:f284/1282c19:dd:d9:dd:c25:c25b:d00a:f284
1342c19:dd:d9:dd:c25:c25b:d00a:f285/1282c19:dd:d9:dd:c25:c25b:d00a:f285
1352c19:dd:d9:dd:c25:c25b:d00a:f286/1282c19:dd:d9:dd:c25:c25b:d00a:f286
1362c19:dd:d9:dd:c25:c25b:d00a:f287/1282c19:dd:d9:dd:c25:c25b:d00a:f287
1372c19:dd:d9:dd:c25:c25b:d00a:f288/1282c19:dd:d9:dd:c25:c25b:d00a:f288
1382c19:dd:d9:dd:c25:c25b:d00a:f289/1282c19:dd:d9:dd:c25:c25b:d00a:f289
1392c19:dd:d9:dd:c25:c25b:d00a:f28a/1282c19:dd:d9:dd:c25:c25b:d00a:f28a
1402c19:dd:d9:dd:c25:c25b:d00a:f28b/1282c19:dd:d9:dd:c25:c25b:d00a:f28b
1412c19:dd:d9:dd:c25:c25b:d00a:f28c/1282c19:dd:d9:dd:c25:c25b:d00a:f28c
1422c19:dd:d9:dd:c25:c25b:d00a:f28d/1282c19:dd:d9:dd:c25:c25b:d00a:f28d
1432c19:dd:d9:dd:c25:c25b:d00a:f28e/1282c19:dd:d9:dd:c25:c25b:d00a:f28e
1442c19:dd:d9:dd:c25:c25b:d00a:f28f/1282c19:dd:d9:dd:c25:c25b:d00a:f28f
1452c19:dd:d9:dd:c25:c25b:d00a:f290/1282c19:dd:d9:dd:c25:c25b:d00a:f290
1462c19:dd:d9:dd:c25:c25b:d00a:f291/1282c19:dd:d9:dd:c25:c25b:d00a:f291
1472c19:dd:d9:dd:c25:c25b:d00a:f292/1282c19:dd:d9:dd:c25:c25b:d00a:f292
1482c19:dd:d9:dd:c25:c25b:d00a:f293/1282c19:dd:d9:dd:c25:c25b:d00a:f293
1492c19:dd:d9:dd:c25:c25b:d00a:f294/1282c19:dd:d9:dd:c25:c25b:d00a:f294
1502c19:dd:d9:dd:c25:c25b:d00a:f295/1282c19:dd:d9:dd:c25:c25b:d00a:f295
1512c19:dd:d9:dd:c25:c25b:d00a:f296/1282c19:dd:d9:dd:c25:c25b:d00a:f296
1522c19:dd:d9:dd:c25:c25b:d00a:f297/1282c19:dd:d9:dd:c25:c25b:d00a:f297
1532c19:dd:d9:dd:c25:c25b:d00a:f298/1282c19:dd:d9:dd:c25:c25b:d00a:f298
1542c19:dd:d9:dd:c25:c25b:d00a:f299/1282c19:dd:d9:dd:c25:c25b:d00a:f299
1552c19:dd:d9:dd:c25:c25b:d00a:f29a/1282c19:dd:d9:dd:c25:c25b:d00a:f29a
1562c19:dd:d9:dd:c25:c25b:d00a:f29b/1282c19:dd:d9:dd:c25:c25b:d00a:f29b
1572c19:dd:d9:dd:c25:c25b:d00a:f29c/1282c19:dd:d9:dd:c25:c25b:d00a:f29c
1582c19:dd:d9:dd:c25:c25b:d00a:f29d/1282c19:dd:d9:dd:c25:c25b:d00a:f29d
1592c19:dd:d9:dd:c25:c25b:d00a:f29e/1282c19:dd:d9:dd:c25:c25b:d00a:f29e
1602c19:dd:d9:dd:c25:c25b:d00a:f29f/1282c19:dd:d9:dd:c25:c25b:d00a:f29f
1612c19:dd:d9:dd:c25:c25b:d00a:f2a0/1282c19:dd:d9:dd:c25:c25b:d00a:f2a0
1622c19:dd:d9:dd:c25:c25b:d00a:f2a1/1282c19:dd:d9:dd:c25:c25b:d00a:f2a1
1632c19:dd:d9:dd:c25:c25b:d00a:f2a2/1282c19:dd:d9:dd:c25:c25b:d00a:f2a2
1642c19:dd:d9:dd:c25:c25b:d00a:f2a3/1282c19:dd:d9:dd:c25:c25b:d00a:f2a3
1652c19:dd:d9:dd:c25:c25b:d00a:f2a4/1282c19:dd:d9:dd:c25:c25b:d00a:f2a4
1662c19:dd:d9:dd:c25:c25b:d00a:f2a5/1282c19:dd:d9:dd:c25:c25b:d00a:f2a5
1672c19:dd:d9:dd:c25:c25b:d00a:f2a6/1282c19:dd:d9:dd:c25:c25b:d00a:f2a6
1682c19:dd:d9:dd:c25:c25b:d00a:f2a7/1282c19:dd:d9:dd:c25:c25b:d00a:f2a7
1692c19:dd:d9:dd:c25:c25b:d00a:f2a8/1282c19:dd:d9:dd:c25:c25b:d00a:f2a8
1702c19:dd:d9:dd:c25:c25b:d00a:f2a9/1282c19:dd:d9:dd:c25:c25b:d00a:f2a9
1712c19:dd:d9:dd:c25:c25b:d00a:f2aa/1282c19:dd:d9:dd:c25:c25b:d00a:f2aa
1722c19:dd:d9:dd:c25:c25b:d00a:f2ab/1282c19:dd:d9:dd:c25:c25b:d00a:f2ab
1732c19:dd:d9:dd:c25:c25b:d00a:f2ac/1282c19:dd:d9:dd:c25:c25b:d00a:f2ac
1742c19:dd:d9:dd:c25:c25b:d00a:f2ad/1282c19:dd:d9:dd:c25:c25b:d00a:f2ad
1752c19:dd:d9:dd:c25:c25b:d00a:f2ae/1282c19:dd:d9:dd:c25:c25b:d00a:f2ae
1762c19:dd:d9:dd:c25:c25b:d00a:f2af/1282c19:dd:d9:dd:c25:c25b:d00a:f2af
1772c19:dd:d9:dd:c25:c25b:d00a:f2b0/1282c19:dd:d9:dd:c25:c25b:d00a:f2b0
1782c19:dd:d9:dd:c25:c25b:d00a:f2b1/1282c19:dd:d9:dd:c25:c25b:d00a:f2b1
1792c19:dd:d9:dd:c25:c25b:d00a:f2b2/1282c19:dd:d9:dd:c25:c25b:d00a:f2b2
1802c19:dd:d9:dd:c25:c25b:d00a:f2b3/1282c19:dd:d9:dd:c25:c25b:d00a:f2b3
1812c19:dd:d9:dd:c25:c25b:d00a:f2b4/1282c19:dd:d9:dd:c25:c25b:d00a:f2b4
1822c19:dd:d9:dd:c25:c25b:d00a:f2b5/1282c19:dd:d9:dd:c25:c25b:d00a:f2b5
1832c19:dd:d9:dd:c25:c25b:d00a:f2b6/1282c19:dd:d9:dd:c25:c25b:d00a:f2b6
1842c19:dd:d9:dd:c25:c25b:d00a:f2b7/1282c19:dd:d9:dd:c25:c25b:d00a:f2b7
1852c19:dd:d9:dd:c25:c25b:d00a:f2b8/1282c19:dd:d9:dd:c25:c25b:d00a:f2b8
1862c19:dd:d9:dd:c25:c25b:d00a:f2b9/1282c19:dd:d9:dd:c25:c25b:d00a:f2b9
1872c19:dd:d9:dd:c25:c25b:d00a:f2ba/1282c19:dd:d9:dd:c25:c25b:d00a:f2ba
1882c19:dd:d9:dd:c25:c25b:d00a:f2bb/1282c19:dd:d9:dd:c25:c25b:d00a:f2bb
1892c19:dd:d9:dd:c25:c25b:d00a:f2bc/1282c19:dd:d9:dd:c25:c25b:d00a:f2bc
1902c19:dd:d9:dd:c25:c25b:d00a:f2bd/1282c19:dd:d9:dd:c25:c25b:d00a:f2bd
1912c19:dd:d9:dd:c25:c25b:d00a:f2be/1282c19:dd:d9:dd:c25:c25b:d00a:f2be
1922c19:dd:d9:dd:c25:c25b:d00a:f2bf/1282c19:dd:d9:dd:c25:c25b:d00a:f2bf
1932c19:dd:d9:dd:c25:c25b:d00a:f2c0/1282c19:dd:d9:dd:c25:c25b:d00a:f2c0
1942c19:dd:d9:dd:c25:c25b:d00a:f2c1/1282c19:dd:d9:dd:c25:c25b:d00a:f2c1
1952c19:dd:d9:dd:c25:c25b:d00a:f2c2/1282c19:dd:d9:dd:c25:c25b:d00a:f2c2
1962c19:dd:d9:dd:c25:c25b:d00a:f2c3/1282c19:dd:d9:dd:c25:c25b:d00a:f2c3
1972c19:dd:d9:dd:c25:c25b:d00a:f2c4/1282c19:dd:d9:dd:c25:c25b:d00a:f2c4
1982c19:dd:d9:dd:c25:c25b:d00a:f2c5/1282c19:dd:d9:dd:c25:c25b:d00a:f2c5
1992c19:dd:d9:dd:c25:c25b:d00a:f2c6/1282c19:dd:d9:dd:c25:c25b:d00a:f2c6
2002c19:dd:d9:dd:c25:c25b:d00a:f2c7/1282c19:dd:d9:dd:c25:c25b:d00a:f2c7
2012c19:dd:d9:dd:c25:c25b:d00a:f2c8/1282c19:dd:d9:dd:c25:c25b:d00a:f2c8
2022c19:dd:d9:dd:c25:c25b:d00a:f2c9/1282c19:dd:d9:dd:c25:c25b:d00a:f2c9
2032c19:dd:d9:dd:c25:c25b:d00a:f2ca/1282c19:dd:d9:dd:c25:c25b:d00a:f2ca
2042c19:dd:d9:dd:c25:c25b:d00a:f2cb/1282c19:dd:d9:dd:c25:c25b:d00a:f2cb
2052c19:dd:d9:dd:c25:c25b:d00a:f2cc/1282c19:dd:d9:dd:c25:c25b:d00a:f2cc
2062c19:dd:d9:dd:c25:c25b:d00a:f2cd/1282c19:dd:d9:dd:c25:c25b:d00a:f2cd
2072c19:dd:d9:dd:c25:c25b:d00a:f2ce/1282c19:dd:d9:dd:c25:c25b:d00a:f2ce
2082c19:dd:d9:dd:c25:c25b:d00a:f2cf/1282c19:dd:d9:dd:c25:c25b:d00a:f2cf
2092c19:dd:d9:dd:c25:c25b:d00a:f2d0/1282c19:dd:d9:dd:c25:c25b:d00a:f2d0
2102c19:dd:d9:dd:c25:c25b:d00a:f2d1/1282c19:dd:d9:dd:c25:c25b:d00a:f2d1
2112c19:dd:d9:dd:c25:c25b:d00a:f2d2/1282c19:dd:d9:dd:c25:c25b:d00a:f2d2
2122c19:dd:d9:dd:c25:c25b:d00a:f2d3/1282c19:dd:d9:dd:c25:c25b:d00a:f2d3
2132c19:dd:d9:dd:c25:c25b:d00a:f2d4/1282c19:dd:d9:dd:c25:c25b:d00a:f2d4
2142c19:dd:d9:dd:c25:c25b:d00a:f2d5/1282c19:dd:d9:dd:c25:c25b:d00a:f2d5
2152c19:dd:d9:dd:c25:c25b:d00a:f2d6/1282c19:dd:d9:dd:c25:c25b:d00a:f2d6
2162c19:dd:d9:dd:c25:c25b:d00a:f2d7/1282c19:dd:d9:dd:c25:c25b:d00a:f2d7
2172c19:dd:d9:dd:c25:c25b:d00a:f2d8/1282c19:dd:d9:dd:c25:c25b:d00a:f2d8
2182c19:dd:d9:dd:c25:c25b:d00a:f2d9/1282c19:dd:d9:dd:c25:c25b:d00a:f2d9
2192c19:dd:d9:dd:c25:c25b:d00a:f2da/1282c19:dd:d9:dd:c25:c25b:d00a:f2da
2202c19:dd:d9:dd:c25:c25b:d00a:f2db/1282c19:dd:d9:dd:c25:c25b:d00a:f2db
2212c19:dd:d9:dd:c25:c25b:d00a:f2dc/1282c19:dd:d9:dd:c25:c25b:d00a:f2dc
2222c19:dd:d9:dd:c25:c25b:d00a:f2dd/1282c19:dd:d9:dd:c25:c25b:d00a:f2dd
2232c19:dd:d9:dd:c25:c25b:d00a:f2de/1282c19:dd:d9:dd:c25:c25b:d00a:f2de
2242c19:dd:d9:dd:c25:c25b:d00a:f2df/1282c19:dd:d9:dd:c25:c25b:d00a:f2df
2252c19:dd:d9:dd:c25:c25b:d00a:f2e0/1282c19:dd:d9:dd:c25:c25b:d00a:f2e0
2262c19:dd:d9:dd:c25:c25b:d00a:f2e1/1282c19:dd:d9:dd:c25:c25b:d00a:f2e1
2272c19:dd:d9:dd:c25:c25b:d00a:f2e2/1282c19:dd:d9:dd:c25:c25b:d00a:f2e2
2282c19:dd:d9:dd:c25:c25b:d00a:f2e3/1282c19:dd:d9:dd:c25:c25b:d00a:f2e3
2292c19:dd:d9:dd:c25:c25b:d00a:f2e4/1282c19:dd:d9:dd:c25:c25b:d00a:f2e4
2302c19:dd:d9:dd:c25:c25b:d00a:f2e5/1282c19:dd:d9:dd:c25:c25b:d00a:f2e5
2312c19:dd:d9:dd:c25:c25b:d00a:f2e6/1282c19:dd:d9:dd:c25:c25b:d00a:f2e6
2322c19:dd:d9:dd:c25:c25b:d00a:f2e7/1282c19:dd:d9:dd:c25:c25b:d00a:f2e7
2332c19:dd:d9:dd:c25:c25b:d00a:f2e8/1282c19:dd:d9:dd:c25:c25b:d00a:f2e8
2342c19:dd:d9:dd:c25:c25b:d00a:f2e9/1282c19:dd:d9:dd:c25:c25b:d00a:f2e9
2352c19:dd:d9:dd:c25:c25b:d00a:f2ea/1282c19:dd:d9:dd:c25:c25b:d00a:f2ea
2362c19:dd:d9:dd:c25:c25b:d00a:f2eb/1282c19:dd:d9:dd:c25:c25b:d00a:f2eb
2372c19:dd:d9:dd:c25:c25b:d00a:f2ec/1282c19:dd:d9:dd:c25:c25b:d00a:f2ec
2382c19:dd:d9:dd:c25:c25b:d00a:f2ed/1282c19:dd:d9:dd:c25:c25b:d00a:f2ed
2392c19:dd:d9:dd:c25:c25b:d00a:f2ee/1282c19:dd:d9:dd:c25:c25b:d00a:f2ee
2402c19:dd:d9:dd:c25:c25b:d00a:f2ef/1282c19:dd:d9:dd:c25:c25b:d00a:f2ef
2412c19:dd:d9:dd:c25:c25b:d00a:f2f0/1282c19:dd:d9:dd:c25:c25b:d00a:f2f0
2422c19:dd:d9:dd:c25:c25b:d00a:f2f1/1282c19:dd:d9:dd:c25:c25b:d00a:f2f1
2432c19:dd:d9:dd:c25:c25b:d00a:f2f2/1282c19:dd:d9:dd:c25:c25b:d00a:f2f2
2442c19:dd:d9:dd:c25:c25b:d00a:f2f3/1282c19:dd:d9:dd:c25:c25b:d00a:f2f3
2452c19:dd:d9:dd:c25:c25b:d00a:f2f4/1282c19:dd:d9:dd:c25:c25b:d00a:f2f4
2462c19:dd:d9:dd:c25:c25b:d00a:f2f5/1282c19:dd:d9:dd:c25:c25b:d00a:f2f5
2472c19:dd:d9:dd:c25:c25b:d00a:f2f6/1282c19:dd:d9:dd:c25:c25b:d00a:f2f6
2482c19:dd:d9:dd:c25:c25b:d00a:f2f7/1282c19:dd:d9:dd:c25:c25b:d00a:f2f7
2492c19:dd:d9:dd:c25:c25b:d00a:f2f8/1282c19:dd:d9:dd:c25:c25b:d00a:f2f8
2502c19:dd:d9:dd:c25:c25b:d00a:f2f9/1282c19:dd:d9:dd:c25:c25b:d00a:f2f9
2512c19:dd:d9:dd:c25:c25b:d00a:f2fa/1282c19:dd:d9:dd:c25:c25b:d00a:f2fa
2522c19:dd:d9:dd:c25:c25b:d00a:f2fb/1282c19:dd:d9:dd:c25:c25b:d00a:f2fb
2532c19:dd:d9:dd:c25:c25b:d00a:f2fc/1282c19:dd:d9:dd:c25:c25b:d00a:f2fc
2542c19:dd:d9:dd:c25:c25b:d00a:f2fd/1282c19:dd:d9:dd:c25:c25b:d00a:f2fd
2552c19:dd:d9:dd:c25:c25b:d00a:f2fe/1282c19:dd:d9:dd:c25:c25b:d00a:f2fe
2562c19:dd:d9:dd:c25:c25b:d00a:f2ff/1282c19:dd:d9:dd:c25:c25b:d00a:f2ff

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.