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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:d915:9200/120
First address
2c19:dd:d9:dd:c25:c25:d915:9200
Last address
2c19:dd:d9:dd:c25:c25:d915:92ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:9200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.9.5.1.9.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:d915:9200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:9200/1282c19:dd:d9:dd:c25:c25:d915:9200
22c19:dd:d9:dd:c25:c25:d915:9201/1282c19:dd:d9:dd:c25:c25:d915:9201
32c19:dd:d9:dd:c25:c25:d915:9202/1282c19:dd:d9:dd:c25:c25:d915:9202
42c19:dd:d9:dd:c25:c25:d915:9203/1282c19:dd:d9:dd:c25:c25:d915:9203
52c19:dd:d9:dd:c25:c25:d915:9204/1282c19:dd:d9:dd:c25:c25:d915:9204
62c19:dd:d9:dd:c25:c25:d915:9205/1282c19:dd:d9:dd:c25:c25:d915:9205
72c19:dd:d9:dd:c25:c25:d915:9206/1282c19:dd:d9:dd:c25:c25:d915:9206
82c19:dd:d9:dd:c25:c25:d915:9207/1282c19:dd:d9:dd:c25:c25:d915:9207
92c19:dd:d9:dd:c25:c25:d915:9208/1282c19:dd:d9:dd:c25:c25:d915:9208
102c19:dd:d9:dd:c25:c25:d915:9209/1282c19:dd:d9:dd:c25:c25:d915:9209
112c19:dd:d9:dd:c25:c25:d915:920a/1282c19:dd:d9:dd:c25:c25:d915:920a
122c19:dd:d9:dd:c25:c25:d915:920b/1282c19:dd:d9:dd:c25:c25:d915:920b
132c19:dd:d9:dd:c25:c25:d915:920c/1282c19:dd:d9:dd:c25:c25:d915:920c
142c19:dd:d9:dd:c25:c25:d915:920d/1282c19:dd:d9:dd:c25:c25:d915:920d
152c19:dd:d9:dd:c25:c25:d915:920e/1282c19:dd:d9:dd:c25:c25:d915:920e
162c19:dd:d9:dd:c25:c25:d915:920f/1282c19:dd:d9:dd:c25:c25:d915:920f
172c19:dd:d9:dd:c25:c25:d915:9210/1282c19:dd:d9:dd:c25:c25:d915:9210
182c19:dd:d9:dd:c25:c25:d915:9211/1282c19:dd:d9:dd:c25:c25:d915:9211
192c19:dd:d9:dd:c25:c25:d915:9212/1282c19:dd:d9:dd:c25:c25:d915:9212
202c19:dd:d9:dd:c25:c25:d915:9213/1282c19:dd:d9:dd:c25:c25:d915:9213
212c19:dd:d9:dd:c25:c25:d915:9214/1282c19:dd:d9:dd:c25:c25:d915:9214
222c19:dd:d9:dd:c25:c25:d915:9215/1282c19:dd:d9:dd:c25:c25:d915:9215
232c19:dd:d9:dd:c25:c25:d915:9216/1282c19:dd:d9:dd:c25:c25:d915:9216
242c19:dd:d9:dd:c25:c25:d915:9217/1282c19:dd:d9:dd:c25:c25:d915:9217
252c19:dd:d9:dd:c25:c25:d915:9218/1282c19:dd:d9:dd:c25:c25:d915:9218
262c19:dd:d9:dd:c25:c25:d915:9219/1282c19:dd:d9:dd:c25:c25:d915:9219
272c19:dd:d9:dd:c25:c25:d915:921a/1282c19:dd:d9:dd:c25:c25:d915:921a
282c19:dd:d9:dd:c25:c25:d915:921b/1282c19:dd:d9:dd:c25:c25:d915:921b
292c19:dd:d9:dd:c25:c25:d915:921c/1282c19:dd:d9:dd:c25:c25:d915:921c
302c19:dd:d9:dd:c25:c25:d915:921d/1282c19:dd:d9:dd:c25:c25:d915:921d
312c19:dd:d9:dd:c25:c25:d915:921e/1282c19:dd:d9:dd:c25:c25:d915:921e
322c19:dd:d9:dd:c25:c25:d915:921f/1282c19:dd:d9:dd:c25:c25:d915:921f
332c19:dd:d9:dd:c25:c25:d915:9220/1282c19:dd:d9:dd:c25:c25:d915:9220
342c19:dd:d9:dd:c25:c25:d915:9221/1282c19:dd:d9:dd:c25:c25:d915:9221
352c19:dd:d9:dd:c25:c25:d915:9222/1282c19:dd:d9:dd:c25:c25:d915:9222
362c19:dd:d9:dd:c25:c25:d915:9223/1282c19:dd:d9:dd:c25:c25:d915:9223
372c19:dd:d9:dd:c25:c25:d915:9224/1282c19:dd:d9:dd:c25:c25:d915:9224
382c19:dd:d9:dd:c25:c25:d915:9225/1282c19:dd:d9:dd:c25:c25:d915:9225
392c19:dd:d9:dd:c25:c25:d915:9226/1282c19:dd:d9:dd:c25:c25:d915:9226
402c19:dd:d9:dd:c25:c25:d915:9227/1282c19:dd:d9:dd:c25:c25:d915:9227
412c19:dd:d9:dd:c25:c25:d915:9228/1282c19:dd:d9:dd:c25:c25:d915:9228
422c19:dd:d9:dd:c25:c25:d915:9229/1282c19:dd:d9:dd:c25:c25:d915:9229
432c19:dd:d9:dd:c25:c25:d915:922a/1282c19:dd:d9:dd:c25:c25:d915:922a
442c19:dd:d9:dd:c25:c25:d915:922b/1282c19:dd:d9:dd:c25:c25:d915:922b
452c19:dd:d9:dd:c25:c25:d915:922c/1282c19:dd:d9:dd:c25:c25:d915:922c
462c19:dd:d9:dd:c25:c25:d915:922d/1282c19:dd:d9:dd:c25:c25:d915:922d
472c19:dd:d9:dd:c25:c25:d915:922e/1282c19:dd:d9:dd:c25:c25:d915:922e
482c19:dd:d9:dd:c25:c25:d915:922f/1282c19:dd:d9:dd:c25:c25:d915:922f
492c19:dd:d9:dd:c25:c25:d915:9230/1282c19:dd:d9:dd:c25:c25:d915:9230
502c19:dd:d9:dd:c25:c25:d915:9231/1282c19:dd:d9:dd:c25:c25:d915:9231
512c19:dd:d9:dd:c25:c25:d915:9232/1282c19:dd:d9:dd:c25:c25:d915:9232
522c19:dd:d9:dd:c25:c25:d915:9233/1282c19:dd:d9:dd:c25:c25:d915:9233
532c19:dd:d9:dd:c25:c25:d915:9234/1282c19:dd:d9:dd:c25:c25:d915:9234
542c19:dd:d9:dd:c25:c25:d915:9235/1282c19:dd:d9:dd:c25:c25:d915:9235
552c19:dd:d9:dd:c25:c25:d915:9236/1282c19:dd:d9:dd:c25:c25:d915:9236
562c19:dd:d9:dd:c25:c25:d915:9237/1282c19:dd:d9:dd:c25:c25:d915:9237
572c19:dd:d9:dd:c25:c25:d915:9238/1282c19:dd:d9:dd:c25:c25:d915:9238
582c19:dd:d9:dd:c25:c25:d915:9239/1282c19:dd:d9:dd:c25:c25:d915:9239
592c19:dd:d9:dd:c25:c25:d915:923a/1282c19:dd:d9:dd:c25:c25:d915:923a
602c19:dd:d9:dd:c25:c25:d915:923b/1282c19:dd:d9:dd:c25:c25:d915:923b
612c19:dd:d9:dd:c25:c25:d915:923c/1282c19:dd:d9:dd:c25:c25:d915:923c
622c19:dd:d9:dd:c25:c25:d915:923d/1282c19:dd:d9:dd:c25:c25:d915:923d
632c19:dd:d9:dd:c25:c25:d915:923e/1282c19:dd:d9:dd:c25:c25:d915:923e
642c19:dd:d9:dd:c25:c25:d915:923f/1282c19:dd:d9:dd:c25:c25:d915:923f
652c19:dd:d9:dd:c25:c25:d915:9240/1282c19:dd:d9:dd:c25:c25:d915:9240
662c19:dd:d9:dd:c25:c25:d915:9241/1282c19:dd:d9:dd:c25:c25:d915:9241
672c19:dd:d9:dd:c25:c25:d915:9242/1282c19:dd:d9:dd:c25:c25:d915:9242
682c19:dd:d9:dd:c25:c25:d915:9243/1282c19:dd:d9:dd:c25:c25:d915:9243
692c19:dd:d9:dd:c25:c25:d915:9244/1282c19:dd:d9:dd:c25:c25:d915:9244
702c19:dd:d9:dd:c25:c25:d915:9245/1282c19:dd:d9:dd:c25:c25:d915:9245
712c19:dd:d9:dd:c25:c25:d915:9246/1282c19:dd:d9:dd:c25:c25:d915:9246
722c19:dd:d9:dd:c25:c25:d915:9247/1282c19:dd:d9:dd:c25:c25:d915:9247
732c19:dd:d9:dd:c25:c25:d915:9248/1282c19:dd:d9:dd:c25:c25:d915:9248
742c19:dd:d9:dd:c25:c25:d915:9249/1282c19:dd:d9:dd:c25:c25:d915:9249
752c19:dd:d9:dd:c25:c25:d915:924a/1282c19:dd:d9:dd:c25:c25:d915:924a
762c19:dd:d9:dd:c25:c25:d915:924b/1282c19:dd:d9:dd:c25:c25:d915:924b
772c19:dd:d9:dd:c25:c25:d915:924c/1282c19:dd:d9:dd:c25:c25:d915:924c
782c19:dd:d9:dd:c25:c25:d915:924d/1282c19:dd:d9:dd:c25:c25:d915:924d
792c19:dd:d9:dd:c25:c25:d915:924e/1282c19:dd:d9:dd:c25:c25:d915:924e
802c19:dd:d9:dd:c25:c25:d915:924f/1282c19:dd:d9:dd:c25:c25:d915:924f
812c19:dd:d9:dd:c25:c25:d915:9250/1282c19:dd:d9:dd:c25:c25:d915:9250
822c19:dd:d9:dd:c25:c25:d915:9251/1282c19:dd:d9:dd:c25:c25:d915:9251
832c19:dd:d9:dd:c25:c25:d915:9252/1282c19:dd:d9:dd:c25:c25:d915:9252
842c19:dd:d9:dd:c25:c25:d915:9253/1282c19:dd:d9:dd:c25:c25:d915:9253
852c19:dd:d9:dd:c25:c25:d915:9254/1282c19:dd:d9:dd:c25:c25:d915:9254
862c19:dd:d9:dd:c25:c25:d915:9255/1282c19:dd:d9:dd:c25:c25:d915:9255
872c19:dd:d9:dd:c25:c25:d915:9256/1282c19:dd:d9:dd:c25:c25:d915:9256
882c19:dd:d9:dd:c25:c25:d915:9257/1282c19:dd:d9:dd:c25:c25:d915:9257
892c19:dd:d9:dd:c25:c25:d915:9258/1282c19:dd:d9:dd:c25:c25:d915:9258
902c19:dd:d9:dd:c25:c25:d915:9259/1282c19:dd:d9:dd:c25:c25:d915:9259
912c19:dd:d9:dd:c25:c25:d915:925a/1282c19:dd:d9:dd:c25:c25:d915:925a
922c19:dd:d9:dd:c25:c25:d915:925b/1282c19:dd:d9:dd:c25:c25:d915:925b
932c19:dd:d9:dd:c25:c25:d915:925c/1282c19:dd:d9:dd:c25:c25:d915:925c
942c19:dd:d9:dd:c25:c25:d915:925d/1282c19:dd:d9:dd:c25:c25:d915:925d
952c19:dd:d9:dd:c25:c25:d915:925e/1282c19:dd:d9:dd:c25:c25:d915:925e
962c19:dd:d9:dd:c25:c25:d915:925f/1282c19:dd:d9:dd:c25:c25:d915:925f
972c19:dd:d9:dd:c25:c25:d915:9260/1282c19:dd:d9:dd:c25:c25:d915:9260
982c19:dd:d9:dd:c25:c25:d915:9261/1282c19:dd:d9:dd:c25:c25:d915:9261
992c19:dd:d9:dd:c25:c25:d915:9262/1282c19:dd:d9:dd:c25:c25:d915:9262
1002c19:dd:d9:dd:c25:c25:d915:9263/1282c19:dd:d9:dd:c25:c25:d915:9263
1012c19:dd:d9:dd:c25:c25:d915:9264/1282c19:dd:d9:dd:c25:c25:d915:9264
1022c19:dd:d9:dd:c25:c25:d915:9265/1282c19:dd:d9:dd:c25:c25:d915:9265
1032c19:dd:d9:dd:c25:c25:d915:9266/1282c19:dd:d9:dd:c25:c25:d915:9266
1042c19:dd:d9:dd:c25:c25:d915:9267/1282c19:dd:d9:dd:c25:c25:d915:9267
1052c19:dd:d9:dd:c25:c25:d915:9268/1282c19:dd:d9:dd:c25:c25:d915:9268
1062c19:dd:d9:dd:c25:c25:d915:9269/1282c19:dd:d9:dd:c25:c25:d915:9269
1072c19:dd:d9:dd:c25:c25:d915:926a/1282c19:dd:d9:dd:c25:c25:d915:926a
1082c19:dd:d9:dd:c25:c25:d915:926b/1282c19:dd:d9:dd:c25:c25:d915:926b
1092c19:dd:d9:dd:c25:c25:d915:926c/1282c19:dd:d9:dd:c25:c25:d915:926c
1102c19:dd:d9:dd:c25:c25:d915:926d/1282c19:dd:d9:dd:c25:c25:d915:926d
1112c19:dd:d9:dd:c25:c25:d915:926e/1282c19:dd:d9:dd:c25:c25:d915:926e
1122c19:dd:d9:dd:c25:c25:d915:926f/1282c19:dd:d9:dd:c25:c25:d915:926f
1132c19:dd:d9:dd:c25:c25:d915:9270/1282c19:dd:d9:dd:c25:c25:d915:9270
1142c19:dd:d9:dd:c25:c25:d915:9271/1282c19:dd:d9:dd:c25:c25:d915:9271
1152c19:dd:d9:dd:c25:c25:d915:9272/1282c19:dd:d9:dd:c25:c25:d915:9272
1162c19:dd:d9:dd:c25:c25:d915:9273/1282c19:dd:d9:dd:c25:c25:d915:9273
1172c19:dd:d9:dd:c25:c25:d915:9274/1282c19:dd:d9:dd:c25:c25:d915:9274
1182c19:dd:d9:dd:c25:c25:d915:9275/1282c19:dd:d9:dd:c25:c25:d915:9275
1192c19:dd:d9:dd:c25:c25:d915:9276/1282c19:dd:d9:dd:c25:c25:d915:9276
1202c19:dd:d9:dd:c25:c25:d915:9277/1282c19:dd:d9:dd:c25:c25:d915:9277
1212c19:dd:d9:dd:c25:c25:d915:9278/1282c19:dd:d9:dd:c25:c25:d915:9278
1222c19:dd:d9:dd:c25:c25:d915:9279/1282c19:dd:d9:dd:c25:c25:d915:9279
1232c19:dd:d9:dd:c25:c25:d915:927a/1282c19:dd:d9:dd:c25:c25:d915:927a
1242c19:dd:d9:dd:c25:c25:d915:927b/1282c19:dd:d9:dd:c25:c25:d915:927b
1252c19:dd:d9:dd:c25:c25:d915:927c/1282c19:dd:d9:dd:c25:c25:d915:927c
1262c19:dd:d9:dd:c25:c25:d915:927d/1282c19:dd:d9:dd:c25:c25:d915:927d
1272c19:dd:d9:dd:c25:c25:d915:927e/1282c19:dd:d9:dd:c25:c25:d915:927e
1282c19:dd:d9:dd:c25:c25:d915:927f/1282c19:dd:d9:dd:c25:c25:d915:927f
1292c19:dd:d9:dd:c25:c25:d915:9280/1282c19:dd:d9:dd:c25:c25:d915:9280
1302c19:dd:d9:dd:c25:c25:d915:9281/1282c19:dd:d9:dd:c25:c25:d915:9281
1312c19:dd:d9:dd:c25:c25:d915:9282/1282c19:dd:d9:dd:c25:c25:d915:9282
1322c19:dd:d9:dd:c25:c25:d915:9283/1282c19:dd:d9:dd:c25:c25:d915:9283
1332c19:dd:d9:dd:c25:c25:d915:9284/1282c19:dd:d9:dd:c25:c25:d915:9284
1342c19:dd:d9:dd:c25:c25:d915:9285/1282c19:dd:d9:dd:c25:c25:d915:9285
1352c19:dd:d9:dd:c25:c25:d915:9286/1282c19:dd:d9:dd:c25:c25:d915:9286
1362c19:dd:d9:dd:c25:c25:d915:9287/1282c19:dd:d9:dd:c25:c25:d915:9287
1372c19:dd:d9:dd:c25:c25:d915:9288/1282c19:dd:d9:dd:c25:c25:d915:9288
1382c19:dd:d9:dd:c25:c25:d915:9289/1282c19:dd:d9:dd:c25:c25:d915:9289
1392c19:dd:d9:dd:c25:c25:d915:928a/1282c19:dd:d9:dd:c25:c25:d915:928a
1402c19:dd:d9:dd:c25:c25:d915:928b/1282c19:dd:d9:dd:c25:c25:d915:928b
1412c19:dd:d9:dd:c25:c25:d915:928c/1282c19:dd:d9:dd:c25:c25:d915:928c
1422c19:dd:d9:dd:c25:c25:d915:928d/1282c19:dd:d9:dd:c25:c25:d915:928d
1432c19:dd:d9:dd:c25:c25:d915:928e/1282c19:dd:d9:dd:c25:c25:d915:928e
1442c19:dd:d9:dd:c25:c25:d915:928f/1282c19:dd:d9:dd:c25:c25:d915:928f
1452c19:dd:d9:dd:c25:c25:d915:9290/1282c19:dd:d9:dd:c25:c25:d915:9290
1462c19:dd:d9:dd:c25:c25:d915:9291/1282c19:dd:d9:dd:c25:c25:d915:9291
1472c19:dd:d9:dd:c25:c25:d915:9292/1282c19:dd:d9:dd:c25:c25:d915:9292
1482c19:dd:d9:dd:c25:c25:d915:9293/1282c19:dd:d9:dd:c25:c25:d915:9293
1492c19:dd:d9:dd:c25:c25:d915:9294/1282c19:dd:d9:dd:c25:c25:d915:9294
1502c19:dd:d9:dd:c25:c25:d915:9295/1282c19:dd:d9:dd:c25:c25:d915:9295
1512c19:dd:d9:dd:c25:c25:d915:9296/1282c19:dd:d9:dd:c25:c25:d915:9296
1522c19:dd:d9:dd:c25:c25:d915:9297/1282c19:dd:d9:dd:c25:c25:d915:9297
1532c19:dd:d9:dd:c25:c25:d915:9298/1282c19:dd:d9:dd:c25:c25:d915:9298
1542c19:dd:d9:dd:c25:c25:d915:9299/1282c19:dd:d9:dd:c25:c25:d915:9299
1552c19:dd:d9:dd:c25:c25:d915:929a/1282c19:dd:d9:dd:c25:c25:d915:929a
1562c19:dd:d9:dd:c25:c25:d915:929b/1282c19:dd:d9:dd:c25:c25:d915:929b
1572c19:dd:d9:dd:c25:c25:d915:929c/1282c19:dd:d9:dd:c25:c25:d915:929c
1582c19:dd:d9:dd:c25:c25:d915:929d/1282c19:dd:d9:dd:c25:c25:d915:929d
1592c19:dd:d9:dd:c25:c25:d915:929e/1282c19:dd:d9:dd:c25:c25:d915:929e
1602c19:dd:d9:dd:c25:c25:d915:929f/1282c19:dd:d9:dd:c25:c25:d915:929f
1612c19:dd:d9:dd:c25:c25:d915:92a0/1282c19:dd:d9:dd:c25:c25:d915:92a0
1622c19:dd:d9:dd:c25:c25:d915:92a1/1282c19:dd:d9:dd:c25:c25:d915:92a1
1632c19:dd:d9:dd:c25:c25:d915:92a2/1282c19:dd:d9:dd:c25:c25:d915:92a2
1642c19:dd:d9:dd:c25:c25:d915:92a3/1282c19:dd:d9:dd:c25:c25:d915:92a3
1652c19:dd:d9:dd:c25:c25:d915:92a4/1282c19:dd:d9:dd:c25:c25:d915:92a4
1662c19:dd:d9:dd:c25:c25:d915:92a5/1282c19:dd:d9:dd:c25:c25:d915:92a5
1672c19:dd:d9:dd:c25:c25:d915:92a6/1282c19:dd:d9:dd:c25:c25:d915:92a6
1682c19:dd:d9:dd:c25:c25:d915:92a7/1282c19:dd:d9:dd:c25:c25:d915:92a7
1692c19:dd:d9:dd:c25:c25:d915:92a8/1282c19:dd:d9:dd:c25:c25:d915:92a8
1702c19:dd:d9:dd:c25:c25:d915:92a9/1282c19:dd:d9:dd:c25:c25:d915:92a9
1712c19:dd:d9:dd:c25:c25:d915:92aa/1282c19:dd:d9:dd:c25:c25:d915:92aa
1722c19:dd:d9:dd:c25:c25:d915:92ab/1282c19:dd:d9:dd:c25:c25:d915:92ab
1732c19:dd:d9:dd:c25:c25:d915:92ac/1282c19:dd:d9:dd:c25:c25:d915:92ac
1742c19:dd:d9:dd:c25:c25:d915:92ad/1282c19:dd:d9:dd:c25:c25:d915:92ad
1752c19:dd:d9:dd:c25:c25:d915:92ae/1282c19:dd:d9:dd:c25:c25:d915:92ae
1762c19:dd:d9:dd:c25:c25:d915:92af/1282c19:dd:d9:dd:c25:c25:d915:92af
1772c19:dd:d9:dd:c25:c25:d915:92b0/1282c19:dd:d9:dd:c25:c25:d915:92b0
1782c19:dd:d9:dd:c25:c25:d915:92b1/1282c19:dd:d9:dd:c25:c25:d915:92b1
1792c19:dd:d9:dd:c25:c25:d915:92b2/1282c19:dd:d9:dd:c25:c25:d915:92b2
1802c19:dd:d9:dd:c25:c25:d915:92b3/1282c19:dd:d9:dd:c25:c25:d915:92b3
1812c19:dd:d9:dd:c25:c25:d915:92b4/1282c19:dd:d9:dd:c25:c25:d915:92b4
1822c19:dd:d9:dd:c25:c25:d915:92b5/1282c19:dd:d9:dd:c25:c25:d915:92b5
1832c19:dd:d9:dd:c25:c25:d915:92b6/1282c19:dd:d9:dd:c25:c25:d915:92b6
1842c19:dd:d9:dd:c25:c25:d915:92b7/1282c19:dd:d9:dd:c25:c25:d915:92b7
1852c19:dd:d9:dd:c25:c25:d915:92b8/1282c19:dd:d9:dd:c25:c25:d915:92b8
1862c19:dd:d9:dd:c25:c25:d915:92b9/1282c19:dd:d9:dd:c25:c25:d915:92b9
1872c19:dd:d9:dd:c25:c25:d915:92ba/1282c19:dd:d9:dd:c25:c25:d915:92ba
1882c19:dd:d9:dd:c25:c25:d915:92bb/1282c19:dd:d9:dd:c25:c25:d915:92bb
1892c19:dd:d9:dd:c25:c25:d915:92bc/1282c19:dd:d9:dd:c25:c25:d915:92bc
1902c19:dd:d9:dd:c25:c25:d915:92bd/1282c19:dd:d9:dd:c25:c25:d915:92bd
1912c19:dd:d9:dd:c25:c25:d915:92be/1282c19:dd:d9:dd:c25:c25:d915:92be
1922c19:dd:d9:dd:c25:c25:d915:92bf/1282c19:dd:d9:dd:c25:c25:d915:92bf
1932c19:dd:d9:dd:c25:c25:d915:92c0/1282c19:dd:d9:dd:c25:c25:d915:92c0
1942c19:dd:d9:dd:c25:c25:d915:92c1/1282c19:dd:d9:dd:c25:c25:d915:92c1
1952c19:dd:d9:dd:c25:c25:d915:92c2/1282c19:dd:d9:dd:c25:c25:d915:92c2
1962c19:dd:d9:dd:c25:c25:d915:92c3/1282c19:dd:d9:dd:c25:c25:d915:92c3
1972c19:dd:d9:dd:c25:c25:d915:92c4/1282c19:dd:d9:dd:c25:c25:d915:92c4
1982c19:dd:d9:dd:c25:c25:d915:92c5/1282c19:dd:d9:dd:c25:c25:d915:92c5
1992c19:dd:d9:dd:c25:c25:d915:92c6/1282c19:dd:d9:dd:c25:c25:d915:92c6
2002c19:dd:d9:dd:c25:c25:d915:92c7/1282c19:dd:d9:dd:c25:c25:d915:92c7
2012c19:dd:d9:dd:c25:c25:d915:92c8/1282c19:dd:d9:dd:c25:c25:d915:92c8
2022c19:dd:d9:dd:c25:c25:d915:92c9/1282c19:dd:d9:dd:c25:c25:d915:92c9
2032c19:dd:d9:dd:c25:c25:d915:92ca/1282c19:dd:d9:dd:c25:c25:d915:92ca
2042c19:dd:d9:dd:c25:c25:d915:92cb/1282c19:dd:d9:dd:c25:c25:d915:92cb
2052c19:dd:d9:dd:c25:c25:d915:92cc/1282c19:dd:d9:dd:c25:c25:d915:92cc
2062c19:dd:d9:dd:c25:c25:d915:92cd/1282c19:dd:d9:dd:c25:c25:d915:92cd
2072c19:dd:d9:dd:c25:c25:d915:92ce/1282c19:dd:d9:dd:c25:c25:d915:92ce
2082c19:dd:d9:dd:c25:c25:d915:92cf/1282c19:dd:d9:dd:c25:c25:d915:92cf
2092c19:dd:d9:dd:c25:c25:d915:92d0/1282c19:dd:d9:dd:c25:c25:d915:92d0
2102c19:dd:d9:dd:c25:c25:d915:92d1/1282c19:dd:d9:dd:c25:c25:d915:92d1
2112c19:dd:d9:dd:c25:c25:d915:92d2/1282c19:dd:d9:dd:c25:c25:d915:92d2
2122c19:dd:d9:dd:c25:c25:d915:92d3/1282c19:dd:d9:dd:c25:c25:d915:92d3
2132c19:dd:d9:dd:c25:c25:d915:92d4/1282c19:dd:d9:dd:c25:c25:d915:92d4
2142c19:dd:d9:dd:c25:c25:d915:92d5/1282c19:dd:d9:dd:c25:c25:d915:92d5
2152c19:dd:d9:dd:c25:c25:d915:92d6/1282c19:dd:d9:dd:c25:c25:d915:92d6
2162c19:dd:d9:dd:c25:c25:d915:92d7/1282c19:dd:d9:dd:c25:c25:d915:92d7
2172c19:dd:d9:dd:c25:c25:d915:92d8/1282c19:dd:d9:dd:c25:c25:d915:92d8
2182c19:dd:d9:dd:c25:c25:d915:92d9/1282c19:dd:d9:dd:c25:c25:d915:92d9
2192c19:dd:d9:dd:c25:c25:d915:92da/1282c19:dd:d9:dd:c25:c25:d915:92da
2202c19:dd:d9:dd:c25:c25:d915:92db/1282c19:dd:d9:dd:c25:c25:d915:92db
2212c19:dd:d9:dd:c25:c25:d915:92dc/1282c19:dd:d9:dd:c25:c25:d915:92dc
2222c19:dd:d9:dd:c25:c25:d915:92dd/1282c19:dd:d9:dd:c25:c25:d915:92dd
2232c19:dd:d9:dd:c25:c25:d915:92de/1282c19:dd:d9:dd:c25:c25:d915:92de
2242c19:dd:d9:dd:c25:c25:d915:92df/1282c19:dd:d9:dd:c25:c25:d915:92df
2252c19:dd:d9:dd:c25:c25:d915:92e0/1282c19:dd:d9:dd:c25:c25:d915:92e0
2262c19:dd:d9:dd:c25:c25:d915:92e1/1282c19:dd:d9:dd:c25:c25:d915:92e1
2272c19:dd:d9:dd:c25:c25:d915:92e2/1282c19:dd:d9:dd:c25:c25:d915:92e2
2282c19:dd:d9:dd:c25:c25:d915:92e3/1282c19:dd:d9:dd:c25:c25:d915:92e3
2292c19:dd:d9:dd:c25:c25:d915:92e4/1282c19:dd:d9:dd:c25:c25:d915:92e4
2302c19:dd:d9:dd:c25:c25:d915:92e5/1282c19:dd:d9:dd:c25:c25:d915:92e5
2312c19:dd:d9:dd:c25:c25:d915:92e6/1282c19:dd:d9:dd:c25:c25:d915:92e6
2322c19:dd:d9:dd:c25:c25:d915:92e7/1282c19:dd:d9:dd:c25:c25:d915:92e7
2332c19:dd:d9:dd:c25:c25:d915:92e8/1282c19:dd:d9:dd:c25:c25:d915:92e8
2342c19:dd:d9:dd:c25:c25:d915:92e9/1282c19:dd:d9:dd:c25:c25:d915:92e9
2352c19:dd:d9:dd:c25:c25:d915:92ea/1282c19:dd:d9:dd:c25:c25:d915:92ea
2362c19:dd:d9:dd:c25:c25:d915:92eb/1282c19:dd:d9:dd:c25:c25:d915:92eb
2372c19:dd:d9:dd:c25:c25:d915:92ec/1282c19:dd:d9:dd:c25:c25:d915:92ec
2382c19:dd:d9:dd:c25:c25:d915:92ed/1282c19:dd:d9:dd:c25:c25:d915:92ed
2392c19:dd:d9:dd:c25:c25:d915:92ee/1282c19:dd:d9:dd:c25:c25:d915:92ee
2402c19:dd:d9:dd:c25:c25:d915:92ef/1282c19:dd:d9:dd:c25:c25:d915:92ef
2412c19:dd:d9:dd:c25:c25:d915:92f0/1282c19:dd:d9:dd:c25:c25:d915:92f0
2422c19:dd:d9:dd:c25:c25:d915:92f1/1282c19:dd:d9:dd:c25:c25:d915:92f1
2432c19:dd:d9:dd:c25:c25:d915:92f2/1282c19:dd:d9:dd:c25:c25:d915:92f2
2442c19:dd:d9:dd:c25:c25:d915:92f3/1282c19:dd:d9:dd:c25:c25:d915:92f3
2452c19:dd:d9:dd:c25:c25:d915:92f4/1282c19:dd:d9:dd:c25:c25:d915:92f4
2462c19:dd:d9:dd:c25:c25:d915:92f5/1282c19:dd:d9:dd:c25:c25:d915:92f5
2472c19:dd:d9:dd:c25:c25:d915:92f6/1282c19:dd:d9:dd:c25:c25:d915:92f6
2482c19:dd:d9:dd:c25:c25:d915:92f7/1282c19:dd:d9:dd:c25:c25:d915:92f7
2492c19:dd:d9:dd:c25:c25:d915:92f8/1282c19:dd:d9:dd:c25:c25:d915:92f8
2502c19:dd:d9:dd:c25:c25:d915:92f9/1282c19:dd:d9:dd:c25:c25:d915:92f9
2512c19:dd:d9:dd:c25:c25:d915:92fa/1282c19:dd:d9:dd:c25:c25:d915:92fa
2522c19:dd:d9:dd:c25:c25:d915:92fb/1282c19:dd:d9:dd:c25:c25:d915:92fb
2532c19:dd:d9:dd:c25:c25:d915:92fc/1282c19:dd:d9:dd:c25:c25:d915:92fc
2542c19:dd:d9:dd:c25:c25:d915:92fd/1282c19:dd:d9:dd:c25:c25:d915:92fd
2552c19:dd:d9:dd:c25:c25:d915:92fe/1282c19:dd:d9:dd:c25:c25:d915:92fe
2562c19:dd:d9:dd:c25:c25:d915:92ff/1282c19:dd:d9:dd:c25:c25:d915:92ff

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.