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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:c25:94de:6300/120
First address
2c19:dd:d9:dd:c25:c25:94de:6300
Last address
2c19:dd:d9:dd:c25:c25:94de:63ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.6.e.d.4.9.5.2.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:c25:94de:6300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6300/1282c19:dd:d9:dd:c25:c25:94de:6300
22c19:dd:d9:dd:c25:c25:94de:6301/1282c19:dd:d9:dd:c25:c25:94de:6301
32c19:dd:d9:dd:c25:c25:94de:6302/1282c19:dd:d9:dd:c25:c25:94de:6302
42c19:dd:d9:dd:c25:c25:94de:6303/1282c19:dd:d9:dd:c25:c25:94de:6303
52c19:dd:d9:dd:c25:c25:94de:6304/1282c19:dd:d9:dd:c25:c25:94de:6304
62c19:dd:d9:dd:c25:c25:94de:6305/1282c19:dd:d9:dd:c25:c25:94de:6305
72c19:dd:d9:dd:c25:c25:94de:6306/1282c19:dd:d9:dd:c25:c25:94de:6306
82c19:dd:d9:dd:c25:c25:94de:6307/1282c19:dd:d9:dd:c25:c25:94de:6307
92c19:dd:d9:dd:c25:c25:94de:6308/1282c19:dd:d9:dd:c25:c25:94de:6308
102c19:dd:d9:dd:c25:c25:94de:6309/1282c19:dd:d9:dd:c25:c25:94de:6309
112c19:dd:d9:dd:c25:c25:94de:630a/1282c19:dd:d9:dd:c25:c25:94de:630a
122c19:dd:d9:dd:c25:c25:94de:630b/1282c19:dd:d9:dd:c25:c25:94de:630b
132c19:dd:d9:dd:c25:c25:94de:630c/1282c19:dd:d9:dd:c25:c25:94de:630c
142c19:dd:d9:dd:c25:c25:94de:630d/1282c19:dd:d9:dd:c25:c25:94de:630d
152c19:dd:d9:dd:c25:c25:94de:630e/1282c19:dd:d9:dd:c25:c25:94de:630e
162c19:dd:d9:dd:c25:c25:94de:630f/1282c19:dd:d9:dd:c25:c25:94de:630f
172c19:dd:d9:dd:c25:c25:94de:6310/1282c19:dd:d9:dd:c25:c25:94de:6310
182c19:dd:d9:dd:c25:c25:94de:6311/1282c19:dd:d9:dd:c25:c25:94de:6311
192c19:dd:d9:dd:c25:c25:94de:6312/1282c19:dd:d9:dd:c25:c25:94de:6312
202c19:dd:d9:dd:c25:c25:94de:6313/1282c19:dd:d9:dd:c25:c25:94de:6313
212c19:dd:d9:dd:c25:c25:94de:6314/1282c19:dd:d9:dd:c25:c25:94de:6314
222c19:dd:d9:dd:c25:c25:94de:6315/1282c19:dd:d9:dd:c25:c25:94de:6315
232c19:dd:d9:dd:c25:c25:94de:6316/1282c19:dd:d9:dd:c25:c25:94de:6316
242c19:dd:d9:dd:c25:c25:94de:6317/1282c19:dd:d9:dd:c25:c25:94de:6317
252c19:dd:d9:dd:c25:c25:94de:6318/1282c19:dd:d9:dd:c25:c25:94de:6318
262c19:dd:d9:dd:c25:c25:94de:6319/1282c19:dd:d9:dd:c25:c25:94de:6319
272c19:dd:d9:dd:c25:c25:94de:631a/1282c19:dd:d9:dd:c25:c25:94de:631a
282c19:dd:d9:dd:c25:c25:94de:631b/1282c19:dd:d9:dd:c25:c25:94de:631b
292c19:dd:d9:dd:c25:c25:94de:631c/1282c19:dd:d9:dd:c25:c25:94de:631c
302c19:dd:d9:dd:c25:c25:94de:631d/1282c19:dd:d9:dd:c25:c25:94de:631d
312c19:dd:d9:dd:c25:c25:94de:631e/1282c19:dd:d9:dd:c25:c25:94de:631e
322c19:dd:d9:dd:c25:c25:94de:631f/1282c19:dd:d9:dd:c25:c25:94de:631f
332c19:dd:d9:dd:c25:c25:94de:6320/1282c19:dd:d9:dd:c25:c25:94de:6320
342c19:dd:d9:dd:c25:c25:94de:6321/1282c19:dd:d9:dd:c25:c25:94de:6321
352c19:dd:d9:dd:c25:c25:94de:6322/1282c19:dd:d9:dd:c25:c25:94de:6322
362c19:dd:d9:dd:c25:c25:94de:6323/1282c19:dd:d9:dd:c25:c25:94de:6323
372c19:dd:d9:dd:c25:c25:94de:6324/1282c19:dd:d9:dd:c25:c25:94de:6324
382c19:dd:d9:dd:c25:c25:94de:6325/1282c19:dd:d9:dd:c25:c25:94de:6325
392c19:dd:d9:dd:c25:c25:94de:6326/1282c19:dd:d9:dd:c25:c25:94de:6326
402c19:dd:d9:dd:c25:c25:94de:6327/1282c19:dd:d9:dd:c25:c25:94de:6327
412c19:dd:d9:dd:c25:c25:94de:6328/1282c19:dd:d9:dd:c25:c25:94de:6328
422c19:dd:d9:dd:c25:c25:94de:6329/1282c19:dd:d9:dd:c25:c25:94de:6329
432c19:dd:d9:dd:c25:c25:94de:632a/1282c19:dd:d9:dd:c25:c25:94de:632a
442c19:dd:d9:dd:c25:c25:94de:632b/1282c19:dd:d9:dd:c25:c25:94de:632b
452c19:dd:d9:dd:c25:c25:94de:632c/1282c19:dd:d9:dd:c25:c25:94de:632c
462c19:dd:d9:dd:c25:c25:94de:632d/1282c19:dd:d9:dd:c25:c25:94de:632d
472c19:dd:d9:dd:c25:c25:94de:632e/1282c19:dd:d9:dd:c25:c25:94de:632e
482c19:dd:d9:dd:c25:c25:94de:632f/1282c19:dd:d9:dd:c25:c25:94de:632f
492c19:dd:d9:dd:c25:c25:94de:6330/1282c19:dd:d9:dd:c25:c25:94de:6330
502c19:dd:d9:dd:c25:c25:94de:6331/1282c19:dd:d9:dd:c25:c25:94de:6331
512c19:dd:d9:dd:c25:c25:94de:6332/1282c19:dd:d9:dd:c25:c25:94de:6332
522c19:dd:d9:dd:c25:c25:94de:6333/1282c19:dd:d9:dd:c25:c25:94de:6333
532c19:dd:d9:dd:c25:c25:94de:6334/1282c19:dd:d9:dd:c25:c25:94de:6334
542c19:dd:d9:dd:c25:c25:94de:6335/1282c19:dd:d9:dd:c25:c25:94de:6335
552c19:dd:d9:dd:c25:c25:94de:6336/1282c19:dd:d9:dd:c25:c25:94de:6336
562c19:dd:d9:dd:c25:c25:94de:6337/1282c19:dd:d9:dd:c25:c25:94de:6337
572c19:dd:d9:dd:c25:c25:94de:6338/1282c19:dd:d9:dd:c25:c25:94de:6338
582c19:dd:d9:dd:c25:c25:94de:6339/1282c19:dd:d9:dd:c25:c25:94de:6339
592c19:dd:d9:dd:c25:c25:94de:633a/1282c19:dd:d9:dd:c25:c25:94de:633a
602c19:dd:d9:dd:c25:c25:94de:633b/1282c19:dd:d9:dd:c25:c25:94de:633b
612c19:dd:d9:dd:c25:c25:94de:633c/1282c19:dd:d9:dd:c25:c25:94de:633c
622c19:dd:d9:dd:c25:c25:94de:633d/1282c19:dd:d9:dd:c25:c25:94de:633d
632c19:dd:d9:dd:c25:c25:94de:633e/1282c19:dd:d9:dd:c25:c25:94de:633e
642c19:dd:d9:dd:c25:c25:94de:633f/1282c19:dd:d9:dd:c25:c25:94de:633f
652c19:dd:d9:dd:c25:c25:94de:6340/1282c19:dd:d9:dd:c25:c25:94de:6340
662c19:dd:d9:dd:c25:c25:94de:6341/1282c19:dd:d9:dd:c25:c25:94de:6341
672c19:dd:d9:dd:c25:c25:94de:6342/1282c19:dd:d9:dd:c25:c25:94de:6342
682c19:dd:d9:dd:c25:c25:94de:6343/1282c19:dd:d9:dd:c25:c25:94de:6343
692c19:dd:d9:dd:c25:c25:94de:6344/1282c19:dd:d9:dd:c25:c25:94de:6344
702c19:dd:d9:dd:c25:c25:94de:6345/1282c19:dd:d9:dd:c25:c25:94de:6345
712c19:dd:d9:dd:c25:c25:94de:6346/1282c19:dd:d9:dd:c25:c25:94de:6346
722c19:dd:d9:dd:c25:c25:94de:6347/1282c19:dd:d9:dd:c25:c25:94de:6347
732c19:dd:d9:dd:c25:c25:94de:6348/1282c19:dd:d9:dd:c25:c25:94de:6348
742c19:dd:d9:dd:c25:c25:94de:6349/1282c19:dd:d9:dd:c25:c25:94de:6349
752c19:dd:d9:dd:c25:c25:94de:634a/1282c19:dd:d9:dd:c25:c25:94de:634a
762c19:dd:d9:dd:c25:c25:94de:634b/1282c19:dd:d9:dd:c25:c25:94de:634b
772c19:dd:d9:dd:c25:c25:94de:634c/1282c19:dd:d9:dd:c25:c25:94de:634c
782c19:dd:d9:dd:c25:c25:94de:634d/1282c19:dd:d9:dd:c25:c25:94de:634d
792c19:dd:d9:dd:c25:c25:94de:634e/1282c19:dd:d9:dd:c25:c25:94de:634e
802c19:dd:d9:dd:c25:c25:94de:634f/1282c19:dd:d9:dd:c25:c25:94de:634f
812c19:dd:d9:dd:c25:c25:94de:6350/1282c19:dd:d9:dd:c25:c25:94de:6350
822c19:dd:d9:dd:c25:c25:94de:6351/1282c19:dd:d9:dd:c25:c25:94de:6351
832c19:dd:d9:dd:c25:c25:94de:6352/1282c19:dd:d9:dd:c25:c25:94de:6352
842c19:dd:d9:dd:c25:c25:94de:6353/1282c19:dd:d9:dd:c25:c25:94de:6353
852c19:dd:d9:dd:c25:c25:94de:6354/1282c19:dd:d9:dd:c25:c25:94de:6354
862c19:dd:d9:dd:c25:c25:94de:6355/1282c19:dd:d9:dd:c25:c25:94de:6355
872c19:dd:d9:dd:c25:c25:94de:6356/1282c19:dd:d9:dd:c25:c25:94de:6356
882c19:dd:d9:dd:c25:c25:94de:6357/1282c19:dd:d9:dd:c25:c25:94de:6357
892c19:dd:d9:dd:c25:c25:94de:6358/1282c19:dd:d9:dd:c25:c25:94de:6358
902c19:dd:d9:dd:c25:c25:94de:6359/1282c19:dd:d9:dd:c25:c25:94de:6359
912c19:dd:d9:dd:c25:c25:94de:635a/1282c19:dd:d9:dd:c25:c25:94de:635a
922c19:dd:d9:dd:c25:c25:94de:635b/1282c19:dd:d9:dd:c25:c25:94de:635b
932c19:dd:d9:dd:c25:c25:94de:635c/1282c19:dd:d9:dd:c25:c25:94de:635c
942c19:dd:d9:dd:c25:c25:94de:635d/1282c19:dd:d9:dd:c25:c25:94de:635d
952c19:dd:d9:dd:c25:c25:94de:635e/1282c19:dd:d9:dd:c25:c25:94de:635e
962c19:dd:d9:dd:c25:c25:94de:635f/1282c19:dd:d9:dd:c25:c25:94de:635f
972c19:dd:d9:dd:c25:c25:94de:6360/1282c19:dd:d9:dd:c25:c25:94de:6360
982c19:dd:d9:dd:c25:c25:94de:6361/1282c19:dd:d9:dd:c25:c25:94de:6361
992c19:dd:d9:dd:c25:c25:94de:6362/1282c19:dd:d9:dd:c25:c25:94de:6362
1002c19:dd:d9:dd:c25:c25:94de:6363/1282c19:dd:d9:dd:c25:c25:94de:6363
1012c19:dd:d9:dd:c25:c25:94de:6364/1282c19:dd:d9:dd:c25:c25:94de:6364
1022c19:dd:d9:dd:c25:c25:94de:6365/1282c19:dd:d9:dd:c25:c25:94de:6365
1032c19:dd:d9:dd:c25:c25:94de:6366/1282c19:dd:d9:dd:c25:c25:94de:6366
1042c19:dd:d9:dd:c25:c25:94de:6367/1282c19:dd:d9:dd:c25:c25:94de:6367
1052c19:dd:d9:dd:c25:c25:94de:6368/1282c19:dd:d9:dd:c25:c25:94de:6368
1062c19:dd:d9:dd:c25:c25:94de:6369/1282c19:dd:d9:dd:c25:c25:94de:6369
1072c19:dd:d9:dd:c25:c25:94de:636a/1282c19:dd:d9:dd:c25:c25:94de:636a
1082c19:dd:d9:dd:c25:c25:94de:636b/1282c19:dd:d9:dd:c25:c25:94de:636b
1092c19:dd:d9:dd:c25:c25:94de:636c/1282c19:dd:d9:dd:c25:c25:94de:636c
1102c19:dd:d9:dd:c25:c25:94de:636d/1282c19:dd:d9:dd:c25:c25:94de:636d
1112c19:dd:d9:dd:c25:c25:94de:636e/1282c19:dd:d9:dd:c25:c25:94de:636e
1122c19:dd:d9:dd:c25:c25:94de:636f/1282c19:dd:d9:dd:c25:c25:94de:636f
1132c19:dd:d9:dd:c25:c25:94de:6370/1282c19:dd:d9:dd:c25:c25:94de:6370
1142c19:dd:d9:dd:c25:c25:94de:6371/1282c19:dd:d9:dd:c25:c25:94de:6371
1152c19:dd:d9:dd:c25:c25:94de:6372/1282c19:dd:d9:dd:c25:c25:94de:6372
1162c19:dd:d9:dd:c25:c25:94de:6373/1282c19:dd:d9:dd:c25:c25:94de:6373
1172c19:dd:d9:dd:c25:c25:94de:6374/1282c19:dd:d9:dd:c25:c25:94de:6374
1182c19:dd:d9:dd:c25:c25:94de:6375/1282c19:dd:d9:dd:c25:c25:94de:6375
1192c19:dd:d9:dd:c25:c25:94de:6376/1282c19:dd:d9:dd:c25:c25:94de:6376
1202c19:dd:d9:dd:c25:c25:94de:6377/1282c19:dd:d9:dd:c25:c25:94de:6377
1212c19:dd:d9:dd:c25:c25:94de:6378/1282c19:dd:d9:dd:c25:c25:94de:6378
1222c19:dd:d9:dd:c25:c25:94de:6379/1282c19:dd:d9:dd:c25:c25:94de:6379
1232c19:dd:d9:dd:c25:c25:94de:637a/1282c19:dd:d9:dd:c25:c25:94de:637a
1242c19:dd:d9:dd:c25:c25:94de:637b/1282c19:dd:d9:dd:c25:c25:94de:637b
1252c19:dd:d9:dd:c25:c25:94de:637c/1282c19:dd:d9:dd:c25:c25:94de:637c
1262c19:dd:d9:dd:c25:c25:94de:637d/1282c19:dd:d9:dd:c25:c25:94de:637d
1272c19:dd:d9:dd:c25:c25:94de:637e/1282c19:dd:d9:dd:c25:c25:94de:637e
1282c19:dd:d9:dd:c25:c25:94de:637f/1282c19:dd:d9:dd:c25:c25:94de:637f
1292c19:dd:d9:dd:c25:c25:94de:6380/1282c19:dd:d9:dd:c25:c25:94de:6380
1302c19:dd:d9:dd:c25:c25:94de:6381/1282c19:dd:d9:dd:c25:c25:94de:6381
1312c19:dd:d9:dd:c25:c25:94de:6382/1282c19:dd:d9:dd:c25:c25:94de:6382
1322c19:dd:d9:dd:c25:c25:94de:6383/1282c19:dd:d9:dd:c25:c25:94de:6383
1332c19:dd:d9:dd:c25:c25:94de:6384/1282c19:dd:d9:dd:c25:c25:94de:6384
1342c19:dd:d9:dd:c25:c25:94de:6385/1282c19:dd:d9:dd:c25:c25:94de:6385
1352c19:dd:d9:dd:c25:c25:94de:6386/1282c19:dd:d9:dd:c25:c25:94de:6386
1362c19:dd:d9:dd:c25:c25:94de:6387/1282c19:dd:d9:dd:c25:c25:94de:6387
1372c19:dd:d9:dd:c25:c25:94de:6388/1282c19:dd:d9:dd:c25:c25:94de:6388
1382c19:dd:d9:dd:c25:c25:94de:6389/1282c19:dd:d9:dd:c25:c25:94de:6389
1392c19:dd:d9:dd:c25:c25:94de:638a/1282c19:dd:d9:dd:c25:c25:94de:638a
1402c19:dd:d9:dd:c25:c25:94de:638b/1282c19:dd:d9:dd:c25:c25:94de:638b
1412c19:dd:d9:dd:c25:c25:94de:638c/1282c19:dd:d9:dd:c25:c25:94de:638c
1422c19:dd:d9:dd:c25:c25:94de:638d/1282c19:dd:d9:dd:c25:c25:94de:638d
1432c19:dd:d9:dd:c25:c25:94de:638e/1282c19:dd:d9:dd:c25:c25:94de:638e
1442c19:dd:d9:dd:c25:c25:94de:638f/1282c19:dd:d9:dd:c25:c25:94de:638f
1452c19:dd:d9:dd:c25:c25:94de:6390/1282c19:dd:d9:dd:c25:c25:94de:6390
1462c19:dd:d9:dd:c25:c25:94de:6391/1282c19:dd:d9:dd:c25:c25:94de:6391
1472c19:dd:d9:dd:c25:c25:94de:6392/1282c19:dd:d9:dd:c25:c25:94de:6392
1482c19:dd:d9:dd:c25:c25:94de:6393/1282c19:dd:d9:dd:c25:c25:94de:6393
1492c19:dd:d9:dd:c25:c25:94de:6394/1282c19:dd:d9:dd:c25:c25:94de:6394
1502c19:dd:d9:dd:c25:c25:94de:6395/1282c19:dd:d9:dd:c25:c25:94de:6395
1512c19:dd:d9:dd:c25:c25:94de:6396/1282c19:dd:d9:dd:c25:c25:94de:6396
1522c19:dd:d9:dd:c25:c25:94de:6397/1282c19:dd:d9:dd:c25:c25:94de:6397
1532c19:dd:d9:dd:c25:c25:94de:6398/1282c19:dd:d9:dd:c25:c25:94de:6398
1542c19:dd:d9:dd:c25:c25:94de:6399/1282c19:dd:d9:dd:c25:c25:94de:6399
1552c19:dd:d9:dd:c25:c25:94de:639a/1282c19:dd:d9:dd:c25:c25:94de:639a
1562c19:dd:d9:dd:c25:c25:94de:639b/1282c19:dd:d9:dd:c25:c25:94de:639b
1572c19:dd:d9:dd:c25:c25:94de:639c/1282c19:dd:d9:dd:c25:c25:94de:639c
1582c19:dd:d9:dd:c25:c25:94de:639d/1282c19:dd:d9:dd:c25:c25:94de:639d
1592c19:dd:d9:dd:c25:c25:94de:639e/1282c19:dd:d9:dd:c25:c25:94de:639e
1602c19:dd:d9:dd:c25:c25:94de:639f/1282c19:dd:d9:dd:c25:c25:94de:639f
1612c19:dd:d9:dd:c25:c25:94de:63a0/1282c19:dd:d9:dd:c25:c25:94de:63a0
1622c19:dd:d9:dd:c25:c25:94de:63a1/1282c19:dd:d9:dd:c25:c25:94de:63a1
1632c19:dd:d9:dd:c25:c25:94de:63a2/1282c19:dd:d9:dd:c25:c25:94de:63a2
1642c19:dd:d9:dd:c25:c25:94de:63a3/1282c19:dd:d9:dd:c25:c25:94de:63a3
1652c19:dd:d9:dd:c25:c25:94de:63a4/1282c19:dd:d9:dd:c25:c25:94de:63a4
1662c19:dd:d9:dd:c25:c25:94de:63a5/1282c19:dd:d9:dd:c25:c25:94de:63a5
1672c19:dd:d9:dd:c25:c25:94de:63a6/1282c19:dd:d9:dd:c25:c25:94de:63a6
1682c19:dd:d9:dd:c25:c25:94de:63a7/1282c19:dd:d9:dd:c25:c25:94de:63a7
1692c19:dd:d9:dd:c25:c25:94de:63a8/1282c19:dd:d9:dd:c25:c25:94de:63a8
1702c19:dd:d9:dd:c25:c25:94de:63a9/1282c19:dd:d9:dd:c25:c25:94de:63a9
1712c19:dd:d9:dd:c25:c25:94de:63aa/1282c19:dd:d9:dd:c25:c25:94de:63aa
1722c19:dd:d9:dd:c25:c25:94de:63ab/1282c19:dd:d9:dd:c25:c25:94de:63ab
1732c19:dd:d9:dd:c25:c25:94de:63ac/1282c19:dd:d9:dd:c25:c25:94de:63ac
1742c19:dd:d9:dd:c25:c25:94de:63ad/1282c19:dd:d9:dd:c25:c25:94de:63ad
1752c19:dd:d9:dd:c25:c25:94de:63ae/1282c19:dd:d9:dd:c25:c25:94de:63ae
1762c19:dd:d9:dd:c25:c25:94de:63af/1282c19:dd:d9:dd:c25:c25:94de:63af
1772c19:dd:d9:dd:c25:c25:94de:63b0/1282c19:dd:d9:dd:c25:c25:94de:63b0
1782c19:dd:d9:dd:c25:c25:94de:63b1/1282c19:dd:d9:dd:c25:c25:94de:63b1
1792c19:dd:d9:dd:c25:c25:94de:63b2/1282c19:dd:d9:dd:c25:c25:94de:63b2
1802c19:dd:d9:dd:c25:c25:94de:63b3/1282c19:dd:d9:dd:c25:c25:94de:63b3
1812c19:dd:d9:dd:c25:c25:94de:63b4/1282c19:dd:d9:dd:c25:c25:94de:63b4
1822c19:dd:d9:dd:c25:c25:94de:63b5/1282c19:dd:d9:dd:c25:c25:94de:63b5
1832c19:dd:d9:dd:c25:c25:94de:63b6/1282c19:dd:d9:dd:c25:c25:94de:63b6
1842c19:dd:d9:dd:c25:c25:94de:63b7/1282c19:dd:d9:dd:c25:c25:94de:63b7
1852c19:dd:d9:dd:c25:c25:94de:63b8/1282c19:dd:d9:dd:c25:c25:94de:63b8
1862c19:dd:d9:dd:c25:c25:94de:63b9/1282c19:dd:d9:dd:c25:c25:94de:63b9
1872c19:dd:d9:dd:c25:c25:94de:63ba/1282c19:dd:d9:dd:c25:c25:94de:63ba
1882c19:dd:d9:dd:c25:c25:94de:63bb/1282c19:dd:d9:dd:c25:c25:94de:63bb
1892c19:dd:d9:dd:c25:c25:94de:63bc/1282c19:dd:d9:dd:c25:c25:94de:63bc
1902c19:dd:d9:dd:c25:c25:94de:63bd/1282c19:dd:d9:dd:c25:c25:94de:63bd
1912c19:dd:d9:dd:c25:c25:94de:63be/1282c19:dd:d9:dd:c25:c25:94de:63be
1922c19:dd:d9:dd:c25:c25:94de:63bf/1282c19:dd:d9:dd:c25:c25:94de:63bf
1932c19:dd:d9:dd:c25:c25:94de:63c0/1282c19:dd:d9:dd:c25:c25:94de:63c0
1942c19:dd:d9:dd:c25:c25:94de:63c1/1282c19:dd:d9:dd:c25:c25:94de:63c1
1952c19:dd:d9:dd:c25:c25:94de:63c2/1282c19:dd:d9:dd:c25:c25:94de:63c2
1962c19:dd:d9:dd:c25:c25:94de:63c3/1282c19:dd:d9:dd:c25:c25:94de:63c3
1972c19:dd:d9:dd:c25:c25:94de:63c4/1282c19:dd:d9:dd:c25:c25:94de:63c4
1982c19:dd:d9:dd:c25:c25:94de:63c5/1282c19:dd:d9:dd:c25:c25:94de:63c5
1992c19:dd:d9:dd:c25:c25:94de:63c6/1282c19:dd:d9:dd:c25:c25:94de:63c6
2002c19:dd:d9:dd:c25:c25:94de:63c7/1282c19:dd:d9:dd:c25:c25:94de:63c7
2012c19:dd:d9:dd:c25:c25:94de:63c8/1282c19:dd:d9:dd:c25:c25:94de:63c8
2022c19:dd:d9:dd:c25:c25:94de:63c9/1282c19:dd:d9:dd:c25:c25:94de:63c9
2032c19:dd:d9:dd:c25:c25:94de:63ca/1282c19:dd:d9:dd:c25:c25:94de:63ca
2042c19:dd:d9:dd:c25:c25:94de:63cb/1282c19:dd:d9:dd:c25:c25:94de:63cb
2052c19:dd:d9:dd:c25:c25:94de:63cc/1282c19:dd:d9:dd:c25:c25:94de:63cc
2062c19:dd:d9:dd:c25:c25:94de:63cd/1282c19:dd:d9:dd:c25:c25:94de:63cd
2072c19:dd:d9:dd:c25:c25:94de:63ce/1282c19:dd:d9:dd:c25:c25:94de:63ce
2082c19:dd:d9:dd:c25:c25:94de:63cf/1282c19:dd:d9:dd:c25:c25:94de:63cf
2092c19:dd:d9:dd:c25:c25:94de:63d0/1282c19:dd:d9:dd:c25:c25:94de:63d0
2102c19:dd:d9:dd:c25:c25:94de:63d1/1282c19:dd:d9:dd:c25:c25:94de:63d1
2112c19:dd:d9:dd:c25:c25:94de:63d2/1282c19:dd:d9:dd:c25:c25:94de:63d2
2122c19:dd:d9:dd:c25:c25:94de:63d3/1282c19:dd:d9:dd:c25:c25:94de:63d3
2132c19:dd:d9:dd:c25:c25:94de:63d4/1282c19:dd:d9:dd:c25:c25:94de:63d4
2142c19:dd:d9:dd:c25:c25:94de:63d5/1282c19:dd:d9:dd:c25:c25:94de:63d5
2152c19:dd:d9:dd:c25:c25:94de:63d6/1282c19:dd:d9:dd:c25:c25:94de:63d6
2162c19:dd:d9:dd:c25:c25:94de:63d7/1282c19:dd:d9:dd:c25:c25:94de:63d7
2172c19:dd:d9:dd:c25:c25:94de:63d8/1282c19:dd:d9:dd:c25:c25:94de:63d8
2182c19:dd:d9:dd:c25:c25:94de:63d9/1282c19:dd:d9:dd:c25:c25:94de:63d9
2192c19:dd:d9:dd:c25:c25:94de:63da/1282c19:dd:d9:dd:c25:c25:94de:63da
2202c19:dd:d9:dd:c25:c25:94de:63db/1282c19:dd:d9:dd:c25:c25:94de:63db
2212c19:dd:d9:dd:c25:c25:94de:63dc/1282c19:dd:d9:dd:c25:c25:94de:63dc
2222c19:dd:d9:dd:c25:c25:94de:63dd/1282c19:dd:d9:dd:c25:c25:94de:63dd
2232c19:dd:d9:dd:c25:c25:94de:63de/1282c19:dd:d9:dd:c25:c25:94de:63de
2242c19:dd:d9:dd:c25:c25:94de:63df/1282c19:dd:d9:dd:c25:c25:94de:63df
2252c19:dd:d9:dd:c25:c25:94de:63e0/1282c19:dd:d9:dd:c25:c25:94de:63e0
2262c19:dd:d9:dd:c25:c25:94de:63e1/1282c19:dd:d9:dd:c25:c25:94de:63e1
2272c19:dd:d9:dd:c25:c25:94de:63e2/1282c19:dd:d9:dd:c25:c25:94de:63e2
2282c19:dd:d9:dd:c25:c25:94de:63e3/1282c19:dd:d9:dd:c25:c25:94de:63e3
2292c19:dd:d9:dd:c25:c25:94de:63e4/1282c19:dd:d9:dd:c25:c25:94de:63e4
2302c19:dd:d9:dd:c25:c25:94de:63e5/1282c19:dd:d9:dd:c25:c25:94de:63e5
2312c19:dd:d9:dd:c25:c25:94de:63e6/1282c19:dd:d9:dd:c25:c25:94de:63e6
2322c19:dd:d9:dd:c25:c25:94de:63e7/1282c19:dd:d9:dd:c25:c25:94de:63e7
2332c19:dd:d9:dd:c25:c25:94de:63e8/1282c19:dd:d9:dd:c25:c25:94de:63e8
2342c19:dd:d9:dd:c25:c25:94de:63e9/1282c19:dd:d9:dd:c25:c25:94de:63e9
2352c19:dd:d9:dd:c25:c25:94de:63ea/1282c19:dd:d9:dd:c25:c25:94de:63ea
2362c19:dd:d9:dd:c25:c25:94de:63eb/1282c19:dd:d9:dd:c25:c25:94de:63eb
2372c19:dd:d9:dd:c25:c25:94de:63ec/1282c19:dd:d9:dd:c25:c25:94de:63ec
2382c19:dd:d9:dd:c25:c25:94de:63ed/1282c19:dd:d9:dd:c25:c25:94de:63ed
2392c19:dd:d9:dd:c25:c25:94de:63ee/1282c19:dd:d9:dd:c25:c25:94de:63ee
2402c19:dd:d9:dd:c25:c25:94de:63ef/1282c19:dd:d9:dd:c25:c25:94de:63ef
2412c19:dd:d9:dd:c25:c25:94de:63f0/1282c19:dd:d9:dd:c25:c25:94de:63f0
2422c19:dd:d9:dd:c25:c25:94de:63f1/1282c19:dd:d9:dd:c25:c25:94de:63f1
2432c19:dd:d9:dd:c25:c25:94de:63f2/1282c19:dd:d9:dd:c25:c25:94de:63f2
2442c19:dd:d9:dd:c25:c25:94de:63f3/1282c19:dd:d9:dd:c25:c25:94de:63f3
2452c19:dd:d9:dd:c25:c25:94de:63f4/1282c19:dd:d9:dd:c25:c25:94de:63f4
2462c19:dd:d9:dd:c25:c25:94de:63f5/1282c19:dd:d9:dd:c25:c25:94de:63f5
2472c19:dd:d9:dd:c25:c25:94de:63f6/1282c19:dd:d9:dd:c25:c25:94de:63f6
2482c19:dd:d9:dd:c25:c25:94de:63f7/1282c19:dd:d9:dd:c25:c25:94de:63f7
2492c19:dd:d9:dd:c25:c25:94de:63f8/1282c19:dd:d9:dd:c25:c25:94de:63f8
2502c19:dd:d9:dd:c25:c25:94de:63f9/1282c19:dd:d9:dd:c25:c25:94de:63f9
2512c19:dd:d9:dd:c25:c25:94de:63fa/1282c19:dd:d9:dd:c25:c25:94de:63fa
2522c19:dd:d9:dd:c25:c25:94de:63fb/1282c19:dd:d9:dd:c25:c25:94de:63fb
2532c19:dd:d9:dd:c25:c25:94de:63fc/1282c19:dd:d9:dd:c25:c25:94de:63fc
2542c19:dd:d9:dd:c25:c25:94de:63fd/1282c19:dd:d9:dd:c25:c25:94de:63fd
2552c19:dd:d9:dd:c25:c25:94de:63fe/1282c19:dd:d9:dd:c25:c25:94de:63fe
2562c19:dd:d9:dd:c25:c25:94de:63ff/1282c19:dd:d9:dd:c25:c25:94de:63ff

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.