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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:d915:8200/120
First address
2c19:dd:d9:dd:c25:c25:d915:8200
Last address
2c19:dd:d9:dd:c25:c25:d915:82ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:8200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.8.5.1.9.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:d915:8200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:8200/1282c19:dd:d9:dd:c25:c25:d915:8200
22c19:dd:d9:dd:c25:c25:d915:8201/1282c19:dd:d9:dd:c25:c25:d915:8201
32c19:dd:d9:dd:c25:c25:d915:8202/1282c19:dd:d9:dd:c25:c25:d915:8202
42c19:dd:d9:dd:c25:c25:d915:8203/1282c19:dd:d9:dd:c25:c25:d915:8203
52c19:dd:d9:dd:c25:c25:d915:8204/1282c19:dd:d9:dd:c25:c25:d915:8204
62c19:dd:d9:dd:c25:c25:d915:8205/1282c19:dd:d9:dd:c25:c25:d915:8205
72c19:dd:d9:dd:c25:c25:d915:8206/1282c19:dd:d9:dd:c25:c25:d915:8206
82c19:dd:d9:dd:c25:c25:d915:8207/1282c19:dd:d9:dd:c25:c25:d915:8207
92c19:dd:d9:dd:c25:c25:d915:8208/1282c19:dd:d9:dd:c25:c25:d915:8208
102c19:dd:d9:dd:c25:c25:d915:8209/1282c19:dd:d9:dd:c25:c25:d915:8209
112c19:dd:d9:dd:c25:c25:d915:820a/1282c19:dd:d9:dd:c25:c25:d915:820a
122c19:dd:d9:dd:c25:c25:d915:820b/1282c19:dd:d9:dd:c25:c25:d915:820b
132c19:dd:d9:dd:c25:c25:d915:820c/1282c19:dd:d9:dd:c25:c25:d915:820c
142c19:dd:d9:dd:c25:c25:d915:820d/1282c19:dd:d9:dd:c25:c25:d915:820d
152c19:dd:d9:dd:c25:c25:d915:820e/1282c19:dd:d9:dd:c25:c25:d915:820e
162c19:dd:d9:dd:c25:c25:d915:820f/1282c19:dd:d9:dd:c25:c25:d915:820f
172c19:dd:d9:dd:c25:c25:d915:8210/1282c19:dd:d9:dd:c25:c25:d915:8210
182c19:dd:d9:dd:c25:c25:d915:8211/1282c19:dd:d9:dd:c25:c25:d915:8211
192c19:dd:d9:dd:c25:c25:d915:8212/1282c19:dd:d9:dd:c25:c25:d915:8212
202c19:dd:d9:dd:c25:c25:d915:8213/1282c19:dd:d9:dd:c25:c25:d915:8213
212c19:dd:d9:dd:c25:c25:d915:8214/1282c19:dd:d9:dd:c25:c25:d915:8214
222c19:dd:d9:dd:c25:c25:d915:8215/1282c19:dd:d9:dd:c25:c25:d915:8215
232c19:dd:d9:dd:c25:c25:d915:8216/1282c19:dd:d9:dd:c25:c25:d915:8216
242c19:dd:d9:dd:c25:c25:d915:8217/1282c19:dd:d9:dd:c25:c25:d915:8217
252c19:dd:d9:dd:c25:c25:d915:8218/1282c19:dd:d9:dd:c25:c25:d915:8218
262c19:dd:d9:dd:c25:c25:d915:8219/1282c19:dd:d9:dd:c25:c25:d915:8219
272c19:dd:d9:dd:c25:c25:d915:821a/1282c19:dd:d9:dd:c25:c25:d915:821a
282c19:dd:d9:dd:c25:c25:d915:821b/1282c19:dd:d9:dd:c25:c25:d915:821b
292c19:dd:d9:dd:c25:c25:d915:821c/1282c19:dd:d9:dd:c25:c25:d915:821c
302c19:dd:d9:dd:c25:c25:d915:821d/1282c19:dd:d9:dd:c25:c25:d915:821d
312c19:dd:d9:dd:c25:c25:d915:821e/1282c19:dd:d9:dd:c25:c25:d915:821e
322c19:dd:d9:dd:c25:c25:d915:821f/1282c19:dd:d9:dd:c25:c25:d915:821f
332c19:dd:d9:dd:c25:c25:d915:8220/1282c19:dd:d9:dd:c25:c25:d915:8220
342c19:dd:d9:dd:c25:c25:d915:8221/1282c19:dd:d9:dd:c25:c25:d915:8221
352c19:dd:d9:dd:c25:c25:d915:8222/1282c19:dd:d9:dd:c25:c25:d915:8222
362c19:dd:d9:dd:c25:c25:d915:8223/1282c19:dd:d9:dd:c25:c25:d915:8223
372c19:dd:d9:dd:c25:c25:d915:8224/1282c19:dd:d9:dd:c25:c25:d915:8224
382c19:dd:d9:dd:c25:c25:d915:8225/1282c19:dd:d9:dd:c25:c25:d915:8225
392c19:dd:d9:dd:c25:c25:d915:8226/1282c19:dd:d9:dd:c25:c25:d915:8226
402c19:dd:d9:dd:c25:c25:d915:8227/1282c19:dd:d9:dd:c25:c25:d915:8227
412c19:dd:d9:dd:c25:c25:d915:8228/1282c19:dd:d9:dd:c25:c25:d915:8228
422c19:dd:d9:dd:c25:c25:d915:8229/1282c19:dd:d9:dd:c25:c25:d915:8229
432c19:dd:d9:dd:c25:c25:d915:822a/1282c19:dd:d9:dd:c25:c25:d915:822a
442c19:dd:d9:dd:c25:c25:d915:822b/1282c19:dd:d9:dd:c25:c25:d915:822b
452c19:dd:d9:dd:c25:c25:d915:822c/1282c19:dd:d9:dd:c25:c25:d915:822c
462c19:dd:d9:dd:c25:c25:d915:822d/1282c19:dd:d9:dd:c25:c25:d915:822d
472c19:dd:d9:dd:c25:c25:d915:822e/1282c19:dd:d9:dd:c25:c25:d915:822e
482c19:dd:d9:dd:c25:c25:d915:822f/1282c19:dd:d9:dd:c25:c25:d915:822f
492c19:dd:d9:dd:c25:c25:d915:8230/1282c19:dd:d9:dd:c25:c25:d915:8230
502c19:dd:d9:dd:c25:c25:d915:8231/1282c19:dd:d9:dd:c25:c25:d915:8231
512c19:dd:d9:dd:c25:c25:d915:8232/1282c19:dd:d9:dd:c25:c25:d915:8232
522c19:dd:d9:dd:c25:c25:d915:8233/1282c19:dd:d9:dd:c25:c25:d915:8233
532c19:dd:d9:dd:c25:c25:d915:8234/1282c19:dd:d9:dd:c25:c25:d915:8234
542c19:dd:d9:dd:c25:c25:d915:8235/1282c19:dd:d9:dd:c25:c25:d915:8235
552c19:dd:d9:dd:c25:c25:d915:8236/1282c19:dd:d9:dd:c25:c25:d915:8236
562c19:dd:d9:dd:c25:c25:d915:8237/1282c19:dd:d9:dd:c25:c25:d915:8237
572c19:dd:d9:dd:c25:c25:d915:8238/1282c19:dd:d9:dd:c25:c25:d915:8238
582c19:dd:d9:dd:c25:c25:d915:8239/1282c19:dd:d9:dd:c25:c25:d915:8239
592c19:dd:d9:dd:c25:c25:d915:823a/1282c19:dd:d9:dd:c25:c25:d915:823a
602c19:dd:d9:dd:c25:c25:d915:823b/1282c19:dd:d9:dd:c25:c25:d915:823b
612c19:dd:d9:dd:c25:c25:d915:823c/1282c19:dd:d9:dd:c25:c25:d915:823c
622c19:dd:d9:dd:c25:c25:d915:823d/1282c19:dd:d9:dd:c25:c25:d915:823d
632c19:dd:d9:dd:c25:c25:d915:823e/1282c19:dd:d9:dd:c25:c25:d915:823e
642c19:dd:d9:dd:c25:c25:d915:823f/1282c19:dd:d9:dd:c25:c25:d915:823f
652c19:dd:d9:dd:c25:c25:d915:8240/1282c19:dd:d9:dd:c25:c25:d915:8240
662c19:dd:d9:dd:c25:c25:d915:8241/1282c19:dd:d9:dd:c25:c25:d915:8241
672c19:dd:d9:dd:c25:c25:d915:8242/1282c19:dd:d9:dd:c25:c25:d915:8242
682c19:dd:d9:dd:c25:c25:d915:8243/1282c19:dd:d9:dd:c25:c25:d915:8243
692c19:dd:d9:dd:c25:c25:d915:8244/1282c19:dd:d9:dd:c25:c25:d915:8244
702c19:dd:d9:dd:c25:c25:d915:8245/1282c19:dd:d9:dd:c25:c25:d915:8245
712c19:dd:d9:dd:c25:c25:d915:8246/1282c19:dd:d9:dd:c25:c25:d915:8246
722c19:dd:d9:dd:c25:c25:d915:8247/1282c19:dd:d9:dd:c25:c25:d915:8247
732c19:dd:d9:dd:c25:c25:d915:8248/1282c19:dd:d9:dd:c25:c25:d915:8248
742c19:dd:d9:dd:c25:c25:d915:8249/1282c19:dd:d9:dd:c25:c25:d915:8249
752c19:dd:d9:dd:c25:c25:d915:824a/1282c19:dd:d9:dd:c25:c25:d915:824a
762c19:dd:d9:dd:c25:c25:d915:824b/1282c19:dd:d9:dd:c25:c25:d915:824b
772c19:dd:d9:dd:c25:c25:d915:824c/1282c19:dd:d9:dd:c25:c25:d915:824c
782c19:dd:d9:dd:c25:c25:d915:824d/1282c19:dd:d9:dd:c25:c25:d915:824d
792c19:dd:d9:dd:c25:c25:d915:824e/1282c19:dd:d9:dd:c25:c25:d915:824e
802c19:dd:d9:dd:c25:c25:d915:824f/1282c19:dd:d9:dd:c25:c25:d915:824f
812c19:dd:d9:dd:c25:c25:d915:8250/1282c19:dd:d9:dd:c25:c25:d915:8250
822c19:dd:d9:dd:c25:c25:d915:8251/1282c19:dd:d9:dd:c25:c25:d915:8251
832c19:dd:d9:dd:c25:c25:d915:8252/1282c19:dd:d9:dd:c25:c25:d915:8252
842c19:dd:d9:dd:c25:c25:d915:8253/1282c19:dd:d9:dd:c25:c25:d915:8253
852c19:dd:d9:dd:c25:c25:d915:8254/1282c19:dd:d9:dd:c25:c25:d915:8254
862c19:dd:d9:dd:c25:c25:d915:8255/1282c19:dd:d9:dd:c25:c25:d915:8255
872c19:dd:d9:dd:c25:c25:d915:8256/1282c19:dd:d9:dd:c25:c25:d915:8256
882c19:dd:d9:dd:c25:c25:d915:8257/1282c19:dd:d9:dd:c25:c25:d915:8257
892c19:dd:d9:dd:c25:c25:d915:8258/1282c19:dd:d9:dd:c25:c25:d915:8258
902c19:dd:d9:dd:c25:c25:d915:8259/1282c19:dd:d9:dd:c25:c25:d915:8259
912c19:dd:d9:dd:c25:c25:d915:825a/1282c19:dd:d9:dd:c25:c25:d915:825a
922c19:dd:d9:dd:c25:c25:d915:825b/1282c19:dd:d9:dd:c25:c25:d915:825b
932c19:dd:d9:dd:c25:c25:d915:825c/1282c19:dd:d9:dd:c25:c25:d915:825c
942c19:dd:d9:dd:c25:c25:d915:825d/1282c19:dd:d9:dd:c25:c25:d915:825d
952c19:dd:d9:dd:c25:c25:d915:825e/1282c19:dd:d9:dd:c25:c25:d915:825e
962c19:dd:d9:dd:c25:c25:d915:825f/1282c19:dd:d9:dd:c25:c25:d915:825f
972c19:dd:d9:dd:c25:c25:d915:8260/1282c19:dd:d9:dd:c25:c25:d915:8260
982c19:dd:d9:dd:c25:c25:d915:8261/1282c19:dd:d9:dd:c25:c25:d915:8261
992c19:dd:d9:dd:c25:c25:d915:8262/1282c19:dd:d9:dd:c25:c25:d915:8262
1002c19:dd:d9:dd:c25:c25:d915:8263/1282c19:dd:d9:dd:c25:c25:d915:8263
1012c19:dd:d9:dd:c25:c25:d915:8264/1282c19:dd:d9:dd:c25:c25:d915:8264
1022c19:dd:d9:dd:c25:c25:d915:8265/1282c19:dd:d9:dd:c25:c25:d915:8265
1032c19:dd:d9:dd:c25:c25:d915:8266/1282c19:dd:d9:dd:c25:c25:d915:8266
1042c19:dd:d9:dd:c25:c25:d915:8267/1282c19:dd:d9:dd:c25:c25:d915:8267
1052c19:dd:d9:dd:c25:c25:d915:8268/1282c19:dd:d9:dd:c25:c25:d915:8268
1062c19:dd:d9:dd:c25:c25:d915:8269/1282c19:dd:d9:dd:c25:c25:d915:8269
1072c19:dd:d9:dd:c25:c25:d915:826a/1282c19:dd:d9:dd:c25:c25:d915:826a
1082c19:dd:d9:dd:c25:c25:d915:826b/1282c19:dd:d9:dd:c25:c25:d915:826b
1092c19:dd:d9:dd:c25:c25:d915:826c/1282c19:dd:d9:dd:c25:c25:d915:826c
1102c19:dd:d9:dd:c25:c25:d915:826d/1282c19:dd:d9:dd:c25:c25:d915:826d
1112c19:dd:d9:dd:c25:c25:d915:826e/1282c19:dd:d9:dd:c25:c25:d915:826e
1122c19:dd:d9:dd:c25:c25:d915:826f/1282c19:dd:d9:dd:c25:c25:d915:826f
1132c19:dd:d9:dd:c25:c25:d915:8270/1282c19:dd:d9:dd:c25:c25:d915:8270
1142c19:dd:d9:dd:c25:c25:d915:8271/1282c19:dd:d9:dd:c25:c25:d915:8271
1152c19:dd:d9:dd:c25:c25:d915:8272/1282c19:dd:d9:dd:c25:c25:d915:8272
1162c19:dd:d9:dd:c25:c25:d915:8273/1282c19:dd:d9:dd:c25:c25:d915:8273
1172c19:dd:d9:dd:c25:c25:d915:8274/1282c19:dd:d9:dd:c25:c25:d915:8274
1182c19:dd:d9:dd:c25:c25:d915:8275/1282c19:dd:d9:dd:c25:c25:d915:8275
1192c19:dd:d9:dd:c25:c25:d915:8276/1282c19:dd:d9:dd:c25:c25:d915:8276
1202c19:dd:d9:dd:c25:c25:d915:8277/1282c19:dd:d9:dd:c25:c25:d915:8277
1212c19:dd:d9:dd:c25:c25:d915:8278/1282c19:dd:d9:dd:c25:c25:d915:8278
1222c19:dd:d9:dd:c25:c25:d915:8279/1282c19:dd:d9:dd:c25:c25:d915:8279
1232c19:dd:d9:dd:c25:c25:d915:827a/1282c19:dd:d9:dd:c25:c25:d915:827a
1242c19:dd:d9:dd:c25:c25:d915:827b/1282c19:dd:d9:dd:c25:c25:d915:827b
1252c19:dd:d9:dd:c25:c25:d915:827c/1282c19:dd:d9:dd:c25:c25:d915:827c
1262c19:dd:d9:dd:c25:c25:d915:827d/1282c19:dd:d9:dd:c25:c25:d915:827d
1272c19:dd:d9:dd:c25:c25:d915:827e/1282c19:dd:d9:dd:c25:c25:d915:827e
1282c19:dd:d9:dd:c25:c25:d915:827f/1282c19:dd:d9:dd:c25:c25:d915:827f
1292c19:dd:d9:dd:c25:c25:d915:8280/1282c19:dd:d9:dd:c25:c25:d915:8280
1302c19:dd:d9:dd:c25:c25:d915:8281/1282c19:dd:d9:dd:c25:c25:d915:8281
1312c19:dd:d9:dd:c25:c25:d915:8282/1282c19:dd:d9:dd:c25:c25:d915:8282
1322c19:dd:d9:dd:c25:c25:d915:8283/1282c19:dd:d9:dd:c25:c25:d915:8283
1332c19:dd:d9:dd:c25:c25:d915:8284/1282c19:dd:d9:dd:c25:c25:d915:8284
1342c19:dd:d9:dd:c25:c25:d915:8285/1282c19:dd:d9:dd:c25:c25:d915:8285
1352c19:dd:d9:dd:c25:c25:d915:8286/1282c19:dd:d9:dd:c25:c25:d915:8286
1362c19:dd:d9:dd:c25:c25:d915:8287/1282c19:dd:d9:dd:c25:c25:d915:8287
1372c19:dd:d9:dd:c25:c25:d915:8288/1282c19:dd:d9:dd:c25:c25:d915:8288
1382c19:dd:d9:dd:c25:c25:d915:8289/1282c19:dd:d9:dd:c25:c25:d915:8289
1392c19:dd:d9:dd:c25:c25:d915:828a/1282c19:dd:d9:dd:c25:c25:d915:828a
1402c19:dd:d9:dd:c25:c25:d915:828b/1282c19:dd:d9:dd:c25:c25:d915:828b
1412c19:dd:d9:dd:c25:c25:d915:828c/1282c19:dd:d9:dd:c25:c25:d915:828c
1422c19:dd:d9:dd:c25:c25:d915:828d/1282c19:dd:d9:dd:c25:c25:d915:828d
1432c19:dd:d9:dd:c25:c25:d915:828e/1282c19:dd:d9:dd:c25:c25:d915:828e
1442c19:dd:d9:dd:c25:c25:d915:828f/1282c19:dd:d9:dd:c25:c25:d915:828f
1452c19:dd:d9:dd:c25:c25:d915:8290/1282c19:dd:d9:dd:c25:c25:d915:8290
1462c19:dd:d9:dd:c25:c25:d915:8291/1282c19:dd:d9:dd:c25:c25:d915:8291
1472c19:dd:d9:dd:c25:c25:d915:8292/1282c19:dd:d9:dd:c25:c25:d915:8292
1482c19:dd:d9:dd:c25:c25:d915:8293/1282c19:dd:d9:dd:c25:c25:d915:8293
1492c19:dd:d9:dd:c25:c25:d915:8294/1282c19:dd:d9:dd:c25:c25:d915:8294
1502c19:dd:d9:dd:c25:c25:d915:8295/1282c19:dd:d9:dd:c25:c25:d915:8295
1512c19:dd:d9:dd:c25:c25:d915:8296/1282c19:dd:d9:dd:c25:c25:d915:8296
1522c19:dd:d9:dd:c25:c25:d915:8297/1282c19:dd:d9:dd:c25:c25:d915:8297
1532c19:dd:d9:dd:c25:c25:d915:8298/1282c19:dd:d9:dd:c25:c25:d915:8298
1542c19:dd:d9:dd:c25:c25:d915:8299/1282c19:dd:d9:dd:c25:c25:d915:8299
1552c19:dd:d9:dd:c25:c25:d915:829a/1282c19:dd:d9:dd:c25:c25:d915:829a
1562c19:dd:d9:dd:c25:c25:d915:829b/1282c19:dd:d9:dd:c25:c25:d915:829b
1572c19:dd:d9:dd:c25:c25:d915:829c/1282c19:dd:d9:dd:c25:c25:d915:829c
1582c19:dd:d9:dd:c25:c25:d915:829d/1282c19:dd:d9:dd:c25:c25:d915:829d
1592c19:dd:d9:dd:c25:c25:d915:829e/1282c19:dd:d9:dd:c25:c25:d915:829e
1602c19:dd:d9:dd:c25:c25:d915:829f/1282c19:dd:d9:dd:c25:c25:d915:829f
1612c19:dd:d9:dd:c25:c25:d915:82a0/1282c19:dd:d9:dd:c25:c25:d915:82a0
1622c19:dd:d9:dd:c25:c25:d915:82a1/1282c19:dd:d9:dd:c25:c25:d915:82a1
1632c19:dd:d9:dd:c25:c25:d915:82a2/1282c19:dd:d9:dd:c25:c25:d915:82a2
1642c19:dd:d9:dd:c25:c25:d915:82a3/1282c19:dd:d9:dd:c25:c25:d915:82a3
1652c19:dd:d9:dd:c25:c25:d915:82a4/1282c19:dd:d9:dd:c25:c25:d915:82a4
1662c19:dd:d9:dd:c25:c25:d915:82a5/1282c19:dd:d9:dd:c25:c25:d915:82a5
1672c19:dd:d9:dd:c25:c25:d915:82a6/1282c19:dd:d9:dd:c25:c25:d915:82a6
1682c19:dd:d9:dd:c25:c25:d915:82a7/1282c19:dd:d9:dd:c25:c25:d915:82a7
1692c19:dd:d9:dd:c25:c25:d915:82a8/1282c19:dd:d9:dd:c25:c25:d915:82a8
1702c19:dd:d9:dd:c25:c25:d915:82a9/1282c19:dd:d9:dd:c25:c25:d915:82a9
1712c19:dd:d9:dd:c25:c25:d915:82aa/1282c19:dd:d9:dd:c25:c25:d915:82aa
1722c19:dd:d9:dd:c25:c25:d915:82ab/1282c19:dd:d9:dd:c25:c25:d915:82ab
1732c19:dd:d9:dd:c25:c25:d915:82ac/1282c19:dd:d9:dd:c25:c25:d915:82ac
1742c19:dd:d9:dd:c25:c25:d915:82ad/1282c19:dd:d9:dd:c25:c25:d915:82ad
1752c19:dd:d9:dd:c25:c25:d915:82ae/1282c19:dd:d9:dd:c25:c25:d915:82ae
1762c19:dd:d9:dd:c25:c25:d915:82af/1282c19:dd:d9:dd:c25:c25:d915:82af
1772c19:dd:d9:dd:c25:c25:d915:82b0/1282c19:dd:d9:dd:c25:c25:d915:82b0
1782c19:dd:d9:dd:c25:c25:d915:82b1/1282c19:dd:d9:dd:c25:c25:d915:82b1
1792c19:dd:d9:dd:c25:c25:d915:82b2/1282c19:dd:d9:dd:c25:c25:d915:82b2
1802c19:dd:d9:dd:c25:c25:d915:82b3/1282c19:dd:d9:dd:c25:c25:d915:82b3
1812c19:dd:d9:dd:c25:c25:d915:82b4/1282c19:dd:d9:dd:c25:c25:d915:82b4
1822c19:dd:d9:dd:c25:c25:d915:82b5/1282c19:dd:d9:dd:c25:c25:d915:82b5
1832c19:dd:d9:dd:c25:c25:d915:82b6/1282c19:dd:d9:dd:c25:c25:d915:82b6
1842c19:dd:d9:dd:c25:c25:d915:82b7/1282c19:dd:d9:dd:c25:c25:d915:82b7
1852c19:dd:d9:dd:c25:c25:d915:82b8/1282c19:dd:d9:dd:c25:c25:d915:82b8
1862c19:dd:d9:dd:c25:c25:d915:82b9/1282c19:dd:d9:dd:c25:c25:d915:82b9
1872c19:dd:d9:dd:c25:c25:d915:82ba/1282c19:dd:d9:dd:c25:c25:d915:82ba
1882c19:dd:d9:dd:c25:c25:d915:82bb/1282c19:dd:d9:dd:c25:c25:d915:82bb
1892c19:dd:d9:dd:c25:c25:d915:82bc/1282c19:dd:d9:dd:c25:c25:d915:82bc
1902c19:dd:d9:dd:c25:c25:d915:82bd/1282c19:dd:d9:dd:c25:c25:d915:82bd
1912c19:dd:d9:dd:c25:c25:d915:82be/1282c19:dd:d9:dd:c25:c25:d915:82be
1922c19:dd:d9:dd:c25:c25:d915:82bf/1282c19:dd:d9:dd:c25:c25:d915:82bf
1932c19:dd:d9:dd:c25:c25:d915:82c0/1282c19:dd:d9:dd:c25:c25:d915:82c0
1942c19:dd:d9:dd:c25:c25:d915:82c1/1282c19:dd:d9:dd:c25:c25:d915:82c1
1952c19:dd:d9:dd:c25:c25:d915:82c2/1282c19:dd:d9:dd:c25:c25:d915:82c2
1962c19:dd:d9:dd:c25:c25:d915:82c3/1282c19:dd:d9:dd:c25:c25:d915:82c3
1972c19:dd:d9:dd:c25:c25:d915:82c4/1282c19:dd:d9:dd:c25:c25:d915:82c4
1982c19:dd:d9:dd:c25:c25:d915:82c5/1282c19:dd:d9:dd:c25:c25:d915:82c5
1992c19:dd:d9:dd:c25:c25:d915:82c6/1282c19:dd:d9:dd:c25:c25:d915:82c6
2002c19:dd:d9:dd:c25:c25:d915:82c7/1282c19:dd:d9:dd:c25:c25:d915:82c7
2012c19:dd:d9:dd:c25:c25:d915:82c8/1282c19:dd:d9:dd:c25:c25:d915:82c8
2022c19:dd:d9:dd:c25:c25:d915:82c9/1282c19:dd:d9:dd:c25:c25:d915:82c9
2032c19:dd:d9:dd:c25:c25:d915:82ca/1282c19:dd:d9:dd:c25:c25:d915:82ca
2042c19:dd:d9:dd:c25:c25:d915:82cb/1282c19:dd:d9:dd:c25:c25:d915:82cb
2052c19:dd:d9:dd:c25:c25:d915:82cc/1282c19:dd:d9:dd:c25:c25:d915:82cc
2062c19:dd:d9:dd:c25:c25:d915:82cd/1282c19:dd:d9:dd:c25:c25:d915:82cd
2072c19:dd:d9:dd:c25:c25:d915:82ce/1282c19:dd:d9:dd:c25:c25:d915:82ce
2082c19:dd:d9:dd:c25:c25:d915:82cf/1282c19:dd:d9:dd:c25:c25:d915:82cf
2092c19:dd:d9:dd:c25:c25:d915:82d0/1282c19:dd:d9:dd:c25:c25:d915:82d0
2102c19:dd:d9:dd:c25:c25:d915:82d1/1282c19:dd:d9:dd:c25:c25:d915:82d1
2112c19:dd:d9:dd:c25:c25:d915:82d2/1282c19:dd:d9:dd:c25:c25:d915:82d2
2122c19:dd:d9:dd:c25:c25:d915:82d3/1282c19:dd:d9:dd:c25:c25:d915:82d3
2132c19:dd:d9:dd:c25:c25:d915:82d4/1282c19:dd:d9:dd:c25:c25:d915:82d4
2142c19:dd:d9:dd:c25:c25:d915:82d5/1282c19:dd:d9:dd:c25:c25:d915:82d5
2152c19:dd:d9:dd:c25:c25:d915:82d6/1282c19:dd:d9:dd:c25:c25:d915:82d6
2162c19:dd:d9:dd:c25:c25:d915:82d7/1282c19:dd:d9:dd:c25:c25:d915:82d7
2172c19:dd:d9:dd:c25:c25:d915:82d8/1282c19:dd:d9:dd:c25:c25:d915:82d8
2182c19:dd:d9:dd:c25:c25:d915:82d9/1282c19:dd:d9:dd:c25:c25:d915:82d9
2192c19:dd:d9:dd:c25:c25:d915:82da/1282c19:dd:d9:dd:c25:c25:d915:82da
2202c19:dd:d9:dd:c25:c25:d915:82db/1282c19:dd:d9:dd:c25:c25:d915:82db
2212c19:dd:d9:dd:c25:c25:d915:82dc/1282c19:dd:d9:dd:c25:c25:d915:82dc
2222c19:dd:d9:dd:c25:c25:d915:82dd/1282c19:dd:d9:dd:c25:c25:d915:82dd
2232c19:dd:d9:dd:c25:c25:d915:82de/1282c19:dd:d9:dd:c25:c25:d915:82de
2242c19:dd:d9:dd:c25:c25:d915:82df/1282c19:dd:d9:dd:c25:c25:d915:82df
2252c19:dd:d9:dd:c25:c25:d915:82e0/1282c19:dd:d9:dd:c25:c25:d915:82e0
2262c19:dd:d9:dd:c25:c25:d915:82e1/1282c19:dd:d9:dd:c25:c25:d915:82e1
2272c19:dd:d9:dd:c25:c25:d915:82e2/1282c19:dd:d9:dd:c25:c25:d915:82e2
2282c19:dd:d9:dd:c25:c25:d915:82e3/1282c19:dd:d9:dd:c25:c25:d915:82e3
2292c19:dd:d9:dd:c25:c25:d915:82e4/1282c19:dd:d9:dd:c25:c25:d915:82e4
2302c19:dd:d9:dd:c25:c25:d915:82e5/1282c19:dd:d9:dd:c25:c25:d915:82e5
2312c19:dd:d9:dd:c25:c25:d915:82e6/1282c19:dd:d9:dd:c25:c25:d915:82e6
2322c19:dd:d9:dd:c25:c25:d915:82e7/1282c19:dd:d9:dd:c25:c25:d915:82e7
2332c19:dd:d9:dd:c25:c25:d915:82e8/1282c19:dd:d9:dd:c25:c25:d915:82e8
2342c19:dd:d9:dd:c25:c25:d915:82e9/1282c19:dd:d9:dd:c25:c25:d915:82e9
2352c19:dd:d9:dd:c25:c25:d915:82ea/1282c19:dd:d9:dd:c25:c25:d915:82ea
2362c19:dd:d9:dd:c25:c25:d915:82eb/1282c19:dd:d9:dd:c25:c25:d915:82eb
2372c19:dd:d9:dd:c25:c25:d915:82ec/1282c19:dd:d9:dd:c25:c25:d915:82ec
2382c19:dd:d9:dd:c25:c25:d915:82ed/1282c19:dd:d9:dd:c25:c25:d915:82ed
2392c19:dd:d9:dd:c25:c25:d915:82ee/1282c19:dd:d9:dd:c25:c25:d915:82ee
2402c19:dd:d9:dd:c25:c25:d915:82ef/1282c19:dd:d9:dd:c25:c25:d915:82ef
2412c19:dd:d9:dd:c25:c25:d915:82f0/1282c19:dd:d9:dd:c25:c25:d915:82f0
2422c19:dd:d9:dd:c25:c25:d915:82f1/1282c19:dd:d9:dd:c25:c25:d915:82f1
2432c19:dd:d9:dd:c25:c25:d915:82f2/1282c19:dd:d9:dd:c25:c25:d915:82f2
2442c19:dd:d9:dd:c25:c25:d915:82f3/1282c19:dd:d9:dd:c25:c25:d915:82f3
2452c19:dd:d9:dd:c25:c25:d915:82f4/1282c19:dd:d9:dd:c25:c25:d915:82f4
2462c19:dd:d9:dd:c25:c25:d915:82f5/1282c19:dd:d9:dd:c25:c25:d915:82f5
2472c19:dd:d9:dd:c25:c25:d915:82f6/1282c19:dd:d9:dd:c25:c25:d915:82f6
2482c19:dd:d9:dd:c25:c25:d915:82f7/1282c19:dd:d9:dd:c25:c25:d915:82f7
2492c19:dd:d9:dd:c25:c25:d915:82f8/1282c19:dd:d9:dd:c25:c25:d915:82f8
2502c19:dd:d9:dd:c25:c25:d915:82f9/1282c19:dd:d9:dd:c25:c25:d915:82f9
2512c19:dd:d9:dd:c25:c25:d915:82fa/1282c19:dd:d9:dd:c25:c25:d915:82fa
2522c19:dd:d9:dd:c25:c25:d915:82fb/1282c19:dd:d9:dd:c25:c25:d915:82fb
2532c19:dd:d9:dd:c25:c25:d915:82fc/1282c19:dd:d9:dd:c25:c25:d915:82fc
2542c19:dd:d9:dd:c25:c25:d915:82fd/1282c19:dd:d9:dd:c25:c25:d915:82fd
2552c19:dd:d9:dd:c25:c25:d915:82fe/1282c19:dd:d9:dd:c25:c25:d915:82fe
2562c19:dd:d9:dd:c25:c25:d915:82ff/1282c19:dd:d9:dd:c25:c25:d915:82ff

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.