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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:6200/120
First address
2c19:dd:d9:dd:c25:c25:94de:6200
Last address
2c19:dd:d9:dd:c25:c25:94de:62ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.6.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:6200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6200/1282c19:dd:d9:dd:c25:c25:94de:6200
22c19:dd:d9:dd:c25:c25:94de:6201/1282c19:dd:d9:dd:c25:c25:94de:6201
32c19:dd:d9:dd:c25:c25:94de:6202/1282c19:dd:d9:dd:c25:c25:94de:6202
42c19:dd:d9:dd:c25:c25:94de:6203/1282c19:dd:d9:dd:c25:c25:94de:6203
52c19:dd:d9:dd:c25:c25:94de:6204/1282c19:dd:d9:dd:c25:c25:94de:6204
62c19:dd:d9:dd:c25:c25:94de:6205/1282c19:dd:d9:dd:c25:c25:94de:6205
72c19:dd:d9:dd:c25:c25:94de:6206/1282c19:dd:d9:dd:c25:c25:94de:6206
82c19:dd:d9:dd:c25:c25:94de:6207/1282c19:dd:d9:dd:c25:c25:94de:6207
92c19:dd:d9:dd:c25:c25:94de:6208/1282c19:dd:d9:dd:c25:c25:94de:6208
102c19:dd:d9:dd:c25:c25:94de:6209/1282c19:dd:d9:dd:c25:c25:94de:6209
112c19:dd:d9:dd:c25:c25:94de:620a/1282c19:dd:d9:dd:c25:c25:94de:620a
122c19:dd:d9:dd:c25:c25:94de:620b/1282c19:dd:d9:dd:c25:c25:94de:620b
132c19:dd:d9:dd:c25:c25:94de:620c/1282c19:dd:d9:dd:c25:c25:94de:620c
142c19:dd:d9:dd:c25:c25:94de:620d/1282c19:dd:d9:dd:c25:c25:94de:620d
152c19:dd:d9:dd:c25:c25:94de:620e/1282c19:dd:d9:dd:c25:c25:94de:620e
162c19:dd:d9:dd:c25:c25:94de:620f/1282c19:dd:d9:dd:c25:c25:94de:620f
172c19:dd:d9:dd:c25:c25:94de:6210/1282c19:dd:d9:dd:c25:c25:94de:6210
182c19:dd:d9:dd:c25:c25:94de:6211/1282c19:dd:d9:dd:c25:c25:94de:6211
192c19:dd:d9:dd:c25:c25:94de:6212/1282c19:dd:d9:dd:c25:c25:94de:6212
202c19:dd:d9:dd:c25:c25:94de:6213/1282c19:dd:d9:dd:c25:c25:94de:6213
212c19:dd:d9:dd:c25:c25:94de:6214/1282c19:dd:d9:dd:c25:c25:94de:6214
222c19:dd:d9:dd:c25:c25:94de:6215/1282c19:dd:d9:dd:c25:c25:94de:6215
232c19:dd:d9:dd:c25:c25:94de:6216/1282c19:dd:d9:dd:c25:c25:94de:6216
242c19:dd:d9:dd:c25:c25:94de:6217/1282c19:dd:d9:dd:c25:c25:94de:6217
252c19:dd:d9:dd:c25:c25:94de:6218/1282c19:dd:d9:dd:c25:c25:94de:6218
262c19:dd:d9:dd:c25:c25:94de:6219/1282c19:dd:d9:dd:c25:c25:94de:6219
272c19:dd:d9:dd:c25:c25:94de:621a/1282c19:dd:d9:dd:c25:c25:94de:621a
282c19:dd:d9:dd:c25:c25:94de:621b/1282c19:dd:d9:dd:c25:c25:94de:621b
292c19:dd:d9:dd:c25:c25:94de:621c/1282c19:dd:d9:dd:c25:c25:94de:621c
302c19:dd:d9:dd:c25:c25:94de:621d/1282c19:dd:d9:dd:c25:c25:94de:621d
312c19:dd:d9:dd:c25:c25:94de:621e/1282c19:dd:d9:dd:c25:c25:94de:621e
322c19:dd:d9:dd:c25:c25:94de:621f/1282c19:dd:d9:dd:c25:c25:94de:621f
332c19:dd:d9:dd:c25:c25:94de:6220/1282c19:dd:d9:dd:c25:c25:94de:6220
342c19:dd:d9:dd:c25:c25:94de:6221/1282c19:dd:d9:dd:c25:c25:94de:6221
352c19:dd:d9:dd:c25:c25:94de:6222/1282c19:dd:d9:dd:c25:c25:94de:6222
362c19:dd:d9:dd:c25:c25:94de:6223/1282c19:dd:d9:dd:c25:c25:94de:6223
372c19:dd:d9:dd:c25:c25:94de:6224/1282c19:dd:d9:dd:c25:c25:94de:6224
382c19:dd:d9:dd:c25:c25:94de:6225/1282c19:dd:d9:dd:c25:c25:94de:6225
392c19:dd:d9:dd:c25:c25:94de:6226/1282c19:dd:d9:dd:c25:c25:94de:6226
402c19:dd:d9:dd:c25:c25:94de:6227/1282c19:dd:d9:dd:c25:c25:94de:6227
412c19:dd:d9:dd:c25:c25:94de:6228/1282c19:dd:d9:dd:c25:c25:94de:6228
422c19:dd:d9:dd:c25:c25:94de:6229/1282c19:dd:d9:dd:c25:c25:94de:6229
432c19:dd:d9:dd:c25:c25:94de:622a/1282c19:dd:d9:dd:c25:c25:94de:622a
442c19:dd:d9:dd:c25:c25:94de:622b/1282c19:dd:d9:dd:c25:c25:94de:622b
452c19:dd:d9:dd:c25:c25:94de:622c/1282c19:dd:d9:dd:c25:c25:94de:622c
462c19:dd:d9:dd:c25:c25:94de:622d/1282c19:dd:d9:dd:c25:c25:94de:622d
472c19:dd:d9:dd:c25:c25:94de:622e/1282c19:dd:d9:dd:c25:c25:94de:622e
482c19:dd:d9:dd:c25:c25:94de:622f/1282c19:dd:d9:dd:c25:c25:94de:622f
492c19:dd:d9:dd:c25:c25:94de:6230/1282c19:dd:d9:dd:c25:c25:94de:6230
502c19:dd:d9:dd:c25:c25:94de:6231/1282c19:dd:d9:dd:c25:c25:94de:6231
512c19:dd:d9:dd:c25:c25:94de:6232/1282c19:dd:d9:dd:c25:c25:94de:6232
522c19:dd:d9:dd:c25:c25:94de:6233/1282c19:dd:d9:dd:c25:c25:94de:6233
532c19:dd:d9:dd:c25:c25:94de:6234/1282c19:dd:d9:dd:c25:c25:94de:6234
542c19:dd:d9:dd:c25:c25:94de:6235/1282c19:dd:d9:dd:c25:c25:94de:6235
552c19:dd:d9:dd:c25:c25:94de:6236/1282c19:dd:d9:dd:c25:c25:94de:6236
562c19:dd:d9:dd:c25:c25:94de:6237/1282c19:dd:d9:dd:c25:c25:94de:6237
572c19:dd:d9:dd:c25:c25:94de:6238/1282c19:dd:d9:dd:c25:c25:94de:6238
582c19:dd:d9:dd:c25:c25:94de:6239/1282c19:dd:d9:dd:c25:c25:94de:6239
592c19:dd:d9:dd:c25:c25:94de:623a/1282c19:dd:d9:dd:c25:c25:94de:623a
602c19:dd:d9:dd:c25:c25:94de:623b/1282c19:dd:d9:dd:c25:c25:94de:623b
612c19:dd:d9:dd:c25:c25:94de:623c/1282c19:dd:d9:dd:c25:c25:94de:623c
622c19:dd:d9:dd:c25:c25:94de:623d/1282c19:dd:d9:dd:c25:c25:94de:623d
632c19:dd:d9:dd:c25:c25:94de:623e/1282c19:dd:d9:dd:c25:c25:94de:623e
642c19:dd:d9:dd:c25:c25:94de:623f/1282c19:dd:d9:dd:c25:c25:94de:623f
652c19:dd:d9:dd:c25:c25:94de:6240/1282c19:dd:d9:dd:c25:c25:94de:6240
662c19:dd:d9:dd:c25:c25:94de:6241/1282c19:dd:d9:dd:c25:c25:94de:6241
672c19:dd:d9:dd:c25:c25:94de:6242/1282c19:dd:d9:dd:c25:c25:94de:6242
682c19:dd:d9:dd:c25:c25:94de:6243/1282c19:dd:d9:dd:c25:c25:94de:6243
692c19:dd:d9:dd:c25:c25:94de:6244/1282c19:dd:d9:dd:c25:c25:94de:6244
702c19:dd:d9:dd:c25:c25:94de:6245/1282c19:dd:d9:dd:c25:c25:94de:6245
712c19:dd:d9:dd:c25:c25:94de:6246/1282c19:dd:d9:dd:c25:c25:94de:6246
722c19:dd:d9:dd:c25:c25:94de:6247/1282c19:dd:d9:dd:c25:c25:94de:6247
732c19:dd:d9:dd:c25:c25:94de:6248/1282c19:dd:d9:dd:c25:c25:94de:6248
742c19:dd:d9:dd:c25:c25:94de:6249/1282c19:dd:d9:dd:c25:c25:94de:6249
752c19:dd:d9:dd:c25:c25:94de:624a/1282c19:dd:d9:dd:c25:c25:94de:624a
762c19:dd:d9:dd:c25:c25:94de:624b/1282c19:dd:d9:dd:c25:c25:94de:624b
772c19:dd:d9:dd:c25:c25:94de:624c/1282c19:dd:d9:dd:c25:c25:94de:624c
782c19:dd:d9:dd:c25:c25:94de:624d/1282c19:dd:d9:dd:c25:c25:94de:624d
792c19:dd:d9:dd:c25:c25:94de:624e/1282c19:dd:d9:dd:c25:c25:94de:624e
802c19:dd:d9:dd:c25:c25:94de:624f/1282c19:dd:d9:dd:c25:c25:94de:624f
812c19:dd:d9:dd:c25:c25:94de:6250/1282c19:dd:d9:dd:c25:c25:94de:6250
822c19:dd:d9:dd:c25:c25:94de:6251/1282c19:dd:d9:dd:c25:c25:94de:6251
832c19:dd:d9:dd:c25:c25:94de:6252/1282c19:dd:d9:dd:c25:c25:94de:6252
842c19:dd:d9:dd:c25:c25:94de:6253/1282c19:dd:d9:dd:c25:c25:94de:6253
852c19:dd:d9:dd:c25:c25:94de:6254/1282c19:dd:d9:dd:c25:c25:94de:6254
862c19:dd:d9:dd:c25:c25:94de:6255/1282c19:dd:d9:dd:c25:c25:94de:6255
872c19:dd:d9:dd:c25:c25:94de:6256/1282c19:dd:d9:dd:c25:c25:94de:6256
882c19:dd:d9:dd:c25:c25:94de:6257/1282c19:dd:d9:dd:c25:c25:94de:6257
892c19:dd:d9:dd:c25:c25:94de:6258/1282c19:dd:d9:dd:c25:c25:94de:6258
902c19:dd:d9:dd:c25:c25:94de:6259/1282c19:dd:d9:dd:c25:c25:94de:6259
912c19:dd:d9:dd:c25:c25:94de:625a/1282c19:dd:d9:dd:c25:c25:94de:625a
922c19:dd:d9:dd:c25:c25:94de:625b/1282c19:dd:d9:dd:c25:c25:94de:625b
932c19:dd:d9:dd:c25:c25:94de:625c/1282c19:dd:d9:dd:c25:c25:94de:625c
942c19:dd:d9:dd:c25:c25:94de:625d/1282c19:dd:d9:dd:c25:c25:94de:625d
952c19:dd:d9:dd:c25:c25:94de:625e/1282c19:dd:d9:dd:c25:c25:94de:625e
962c19:dd:d9:dd:c25:c25:94de:625f/1282c19:dd:d9:dd:c25:c25:94de:625f
972c19:dd:d9:dd:c25:c25:94de:6260/1282c19:dd:d9:dd:c25:c25:94de:6260
982c19:dd:d9:dd:c25:c25:94de:6261/1282c19:dd:d9:dd:c25:c25:94de:6261
992c19:dd:d9:dd:c25:c25:94de:6262/1282c19:dd:d9:dd:c25:c25:94de:6262
1002c19:dd:d9:dd:c25:c25:94de:6263/1282c19:dd:d9:dd:c25:c25:94de:6263
1012c19:dd:d9:dd:c25:c25:94de:6264/1282c19:dd:d9:dd:c25:c25:94de:6264
1022c19:dd:d9:dd:c25:c25:94de:6265/1282c19:dd:d9:dd:c25:c25:94de:6265
1032c19:dd:d9:dd:c25:c25:94de:6266/1282c19:dd:d9:dd:c25:c25:94de:6266
1042c19:dd:d9:dd:c25:c25:94de:6267/1282c19:dd:d9:dd:c25:c25:94de:6267
1052c19:dd:d9:dd:c25:c25:94de:6268/1282c19:dd:d9:dd:c25:c25:94de:6268
1062c19:dd:d9:dd:c25:c25:94de:6269/1282c19:dd:d9:dd:c25:c25:94de:6269
1072c19:dd:d9:dd:c25:c25:94de:626a/1282c19:dd:d9:dd:c25:c25:94de:626a
1082c19:dd:d9:dd:c25:c25:94de:626b/1282c19:dd:d9:dd:c25:c25:94de:626b
1092c19:dd:d9:dd:c25:c25:94de:626c/1282c19:dd:d9:dd:c25:c25:94de:626c
1102c19:dd:d9:dd:c25:c25:94de:626d/1282c19:dd:d9:dd:c25:c25:94de:626d
1112c19:dd:d9:dd:c25:c25:94de:626e/1282c19:dd:d9:dd:c25:c25:94de:626e
1122c19:dd:d9:dd:c25:c25:94de:626f/1282c19:dd:d9:dd:c25:c25:94de:626f
1132c19:dd:d9:dd:c25:c25:94de:6270/1282c19:dd:d9:dd:c25:c25:94de:6270
1142c19:dd:d9:dd:c25:c25:94de:6271/1282c19:dd:d9:dd:c25:c25:94de:6271
1152c19:dd:d9:dd:c25:c25:94de:6272/1282c19:dd:d9:dd:c25:c25:94de:6272
1162c19:dd:d9:dd:c25:c25:94de:6273/1282c19:dd:d9:dd:c25:c25:94de:6273
1172c19:dd:d9:dd:c25:c25:94de:6274/1282c19:dd:d9:dd:c25:c25:94de:6274
1182c19:dd:d9:dd:c25:c25:94de:6275/1282c19:dd:d9:dd:c25:c25:94de:6275
1192c19:dd:d9:dd:c25:c25:94de:6276/1282c19:dd:d9:dd:c25:c25:94de:6276
1202c19:dd:d9:dd:c25:c25:94de:6277/1282c19:dd:d9:dd:c25:c25:94de:6277
1212c19:dd:d9:dd:c25:c25:94de:6278/1282c19:dd:d9:dd:c25:c25:94de:6278
1222c19:dd:d9:dd:c25:c25:94de:6279/1282c19:dd:d9:dd:c25:c25:94de:6279
1232c19:dd:d9:dd:c25:c25:94de:627a/1282c19:dd:d9:dd:c25:c25:94de:627a
1242c19:dd:d9:dd:c25:c25:94de:627b/1282c19:dd:d9:dd:c25:c25:94de:627b
1252c19:dd:d9:dd:c25:c25:94de:627c/1282c19:dd:d9:dd:c25:c25:94de:627c
1262c19:dd:d9:dd:c25:c25:94de:627d/1282c19:dd:d9:dd:c25:c25:94de:627d
1272c19:dd:d9:dd:c25:c25:94de:627e/1282c19:dd:d9:dd:c25:c25:94de:627e
1282c19:dd:d9:dd:c25:c25:94de:627f/1282c19:dd:d9:dd:c25:c25:94de:627f
1292c19:dd:d9:dd:c25:c25:94de:6280/1282c19:dd:d9:dd:c25:c25:94de:6280
1302c19:dd:d9:dd:c25:c25:94de:6281/1282c19:dd:d9:dd:c25:c25:94de:6281
1312c19:dd:d9:dd:c25:c25:94de:6282/1282c19:dd:d9:dd:c25:c25:94de:6282
1322c19:dd:d9:dd:c25:c25:94de:6283/1282c19:dd:d9:dd:c25:c25:94de:6283
1332c19:dd:d9:dd:c25:c25:94de:6284/1282c19:dd:d9:dd:c25:c25:94de:6284
1342c19:dd:d9:dd:c25:c25:94de:6285/1282c19:dd:d9:dd:c25:c25:94de:6285
1352c19:dd:d9:dd:c25:c25:94de:6286/1282c19:dd:d9:dd:c25:c25:94de:6286
1362c19:dd:d9:dd:c25:c25:94de:6287/1282c19:dd:d9:dd:c25:c25:94de:6287
1372c19:dd:d9:dd:c25:c25:94de:6288/1282c19:dd:d9:dd:c25:c25:94de:6288
1382c19:dd:d9:dd:c25:c25:94de:6289/1282c19:dd:d9:dd:c25:c25:94de:6289
1392c19:dd:d9:dd:c25:c25:94de:628a/1282c19:dd:d9:dd:c25:c25:94de:628a
1402c19:dd:d9:dd:c25:c25:94de:628b/1282c19:dd:d9:dd:c25:c25:94de:628b
1412c19:dd:d9:dd:c25:c25:94de:628c/1282c19:dd:d9:dd:c25:c25:94de:628c
1422c19:dd:d9:dd:c25:c25:94de:628d/1282c19:dd:d9:dd:c25:c25:94de:628d
1432c19:dd:d9:dd:c25:c25:94de:628e/1282c19:dd:d9:dd:c25:c25:94de:628e
1442c19:dd:d9:dd:c25:c25:94de:628f/1282c19:dd:d9:dd:c25:c25:94de:628f
1452c19:dd:d9:dd:c25:c25:94de:6290/1282c19:dd:d9:dd:c25:c25:94de:6290
1462c19:dd:d9:dd:c25:c25:94de:6291/1282c19:dd:d9:dd:c25:c25:94de:6291
1472c19:dd:d9:dd:c25:c25:94de:6292/1282c19:dd:d9:dd:c25:c25:94de:6292
1482c19:dd:d9:dd:c25:c25:94de:6293/1282c19:dd:d9:dd:c25:c25:94de:6293
1492c19:dd:d9:dd:c25:c25:94de:6294/1282c19:dd:d9:dd:c25:c25:94de:6294
1502c19:dd:d9:dd:c25:c25:94de:6295/1282c19:dd:d9:dd:c25:c25:94de:6295
1512c19:dd:d9:dd:c25:c25:94de:6296/1282c19:dd:d9:dd:c25:c25:94de:6296
1522c19:dd:d9:dd:c25:c25:94de:6297/1282c19:dd:d9:dd:c25:c25:94de:6297
1532c19:dd:d9:dd:c25:c25:94de:6298/1282c19:dd:d9:dd:c25:c25:94de:6298
1542c19:dd:d9:dd:c25:c25:94de:6299/1282c19:dd:d9:dd:c25:c25:94de:6299
1552c19:dd:d9:dd:c25:c25:94de:629a/1282c19:dd:d9:dd:c25:c25:94de:629a
1562c19:dd:d9:dd:c25:c25:94de:629b/1282c19:dd:d9:dd:c25:c25:94de:629b
1572c19:dd:d9:dd:c25:c25:94de:629c/1282c19:dd:d9:dd:c25:c25:94de:629c
1582c19:dd:d9:dd:c25:c25:94de:629d/1282c19:dd:d9:dd:c25:c25:94de:629d
1592c19:dd:d9:dd:c25:c25:94de:629e/1282c19:dd:d9:dd:c25:c25:94de:629e
1602c19:dd:d9:dd:c25:c25:94de:629f/1282c19:dd:d9:dd:c25:c25:94de:629f
1612c19:dd:d9:dd:c25:c25:94de:62a0/1282c19:dd:d9:dd:c25:c25:94de:62a0
1622c19:dd:d9:dd:c25:c25:94de:62a1/1282c19:dd:d9:dd:c25:c25:94de:62a1
1632c19:dd:d9:dd:c25:c25:94de:62a2/1282c19:dd:d9:dd:c25:c25:94de:62a2
1642c19:dd:d9:dd:c25:c25:94de:62a3/1282c19:dd:d9:dd:c25:c25:94de:62a3
1652c19:dd:d9:dd:c25:c25:94de:62a4/1282c19:dd:d9:dd:c25:c25:94de:62a4
1662c19:dd:d9:dd:c25:c25:94de:62a5/1282c19:dd:d9:dd:c25:c25:94de:62a5
1672c19:dd:d9:dd:c25:c25:94de:62a6/1282c19:dd:d9:dd:c25:c25:94de:62a6
1682c19:dd:d9:dd:c25:c25:94de:62a7/1282c19:dd:d9:dd:c25:c25:94de:62a7
1692c19:dd:d9:dd:c25:c25:94de:62a8/1282c19:dd:d9:dd:c25:c25:94de:62a8
1702c19:dd:d9:dd:c25:c25:94de:62a9/1282c19:dd:d9:dd:c25:c25:94de:62a9
1712c19:dd:d9:dd:c25:c25:94de:62aa/1282c19:dd:d9:dd:c25:c25:94de:62aa
1722c19:dd:d9:dd:c25:c25:94de:62ab/1282c19:dd:d9:dd:c25:c25:94de:62ab
1732c19:dd:d9:dd:c25:c25:94de:62ac/1282c19:dd:d9:dd:c25:c25:94de:62ac
1742c19:dd:d9:dd:c25:c25:94de:62ad/1282c19:dd:d9:dd:c25:c25:94de:62ad
1752c19:dd:d9:dd:c25:c25:94de:62ae/1282c19:dd:d9:dd:c25:c25:94de:62ae
1762c19:dd:d9:dd:c25:c25:94de:62af/1282c19:dd:d9:dd:c25:c25:94de:62af
1772c19:dd:d9:dd:c25:c25:94de:62b0/1282c19:dd:d9:dd:c25:c25:94de:62b0
1782c19:dd:d9:dd:c25:c25:94de:62b1/1282c19:dd:d9:dd:c25:c25:94de:62b1
1792c19:dd:d9:dd:c25:c25:94de:62b2/1282c19:dd:d9:dd:c25:c25:94de:62b2
1802c19:dd:d9:dd:c25:c25:94de:62b3/1282c19:dd:d9:dd:c25:c25:94de:62b3
1812c19:dd:d9:dd:c25:c25:94de:62b4/1282c19:dd:d9:dd:c25:c25:94de:62b4
1822c19:dd:d9:dd:c25:c25:94de:62b5/1282c19:dd:d9:dd:c25:c25:94de:62b5
1832c19:dd:d9:dd:c25:c25:94de:62b6/1282c19:dd:d9:dd:c25:c25:94de:62b6
1842c19:dd:d9:dd:c25:c25:94de:62b7/1282c19:dd:d9:dd:c25:c25:94de:62b7
1852c19:dd:d9:dd:c25:c25:94de:62b8/1282c19:dd:d9:dd:c25:c25:94de:62b8
1862c19:dd:d9:dd:c25:c25:94de:62b9/1282c19:dd:d9:dd:c25:c25:94de:62b9
1872c19:dd:d9:dd:c25:c25:94de:62ba/1282c19:dd:d9:dd:c25:c25:94de:62ba
1882c19:dd:d9:dd:c25:c25:94de:62bb/1282c19:dd:d9:dd:c25:c25:94de:62bb
1892c19:dd:d9:dd:c25:c25:94de:62bc/1282c19:dd:d9:dd:c25:c25:94de:62bc
1902c19:dd:d9:dd:c25:c25:94de:62bd/1282c19:dd:d9:dd:c25:c25:94de:62bd
1912c19:dd:d9:dd:c25:c25:94de:62be/1282c19:dd:d9:dd:c25:c25:94de:62be
1922c19:dd:d9:dd:c25:c25:94de:62bf/1282c19:dd:d9:dd:c25:c25:94de:62bf
1932c19:dd:d9:dd:c25:c25:94de:62c0/1282c19:dd:d9:dd:c25:c25:94de:62c0
1942c19:dd:d9:dd:c25:c25:94de:62c1/1282c19:dd:d9:dd:c25:c25:94de:62c1
1952c19:dd:d9:dd:c25:c25:94de:62c2/1282c19:dd:d9:dd:c25:c25:94de:62c2
1962c19:dd:d9:dd:c25:c25:94de:62c3/1282c19:dd:d9:dd:c25:c25:94de:62c3
1972c19:dd:d9:dd:c25:c25:94de:62c4/1282c19:dd:d9:dd:c25:c25:94de:62c4
1982c19:dd:d9:dd:c25:c25:94de:62c5/1282c19:dd:d9:dd:c25:c25:94de:62c5
1992c19:dd:d9:dd:c25:c25:94de:62c6/1282c19:dd:d9:dd:c25:c25:94de:62c6
2002c19:dd:d9:dd:c25:c25:94de:62c7/1282c19:dd:d9:dd:c25:c25:94de:62c7
2012c19:dd:d9:dd:c25:c25:94de:62c8/1282c19:dd:d9:dd:c25:c25:94de:62c8
2022c19:dd:d9:dd:c25:c25:94de:62c9/1282c19:dd:d9:dd:c25:c25:94de:62c9
2032c19:dd:d9:dd:c25:c25:94de:62ca/1282c19:dd:d9:dd:c25:c25:94de:62ca
2042c19:dd:d9:dd:c25:c25:94de:62cb/1282c19:dd:d9:dd:c25:c25:94de:62cb
2052c19:dd:d9:dd:c25:c25:94de:62cc/1282c19:dd:d9:dd:c25:c25:94de:62cc
2062c19:dd:d9:dd:c25:c25:94de:62cd/1282c19:dd:d9:dd:c25:c25:94de:62cd
2072c19:dd:d9:dd:c25:c25:94de:62ce/1282c19:dd:d9:dd:c25:c25:94de:62ce
2082c19:dd:d9:dd:c25:c25:94de:62cf/1282c19:dd:d9:dd:c25:c25:94de:62cf
2092c19:dd:d9:dd:c25:c25:94de:62d0/1282c19:dd:d9:dd:c25:c25:94de:62d0
2102c19:dd:d9:dd:c25:c25:94de:62d1/1282c19:dd:d9:dd:c25:c25:94de:62d1
2112c19:dd:d9:dd:c25:c25:94de:62d2/1282c19:dd:d9:dd:c25:c25:94de:62d2
2122c19:dd:d9:dd:c25:c25:94de:62d3/1282c19:dd:d9:dd:c25:c25:94de:62d3
2132c19:dd:d9:dd:c25:c25:94de:62d4/1282c19:dd:d9:dd:c25:c25:94de:62d4
2142c19:dd:d9:dd:c25:c25:94de:62d5/1282c19:dd:d9:dd:c25:c25:94de:62d5
2152c19:dd:d9:dd:c25:c25:94de:62d6/1282c19:dd:d9:dd:c25:c25:94de:62d6
2162c19:dd:d9:dd:c25:c25:94de:62d7/1282c19:dd:d9:dd:c25:c25:94de:62d7
2172c19:dd:d9:dd:c25:c25:94de:62d8/1282c19:dd:d9:dd:c25:c25:94de:62d8
2182c19:dd:d9:dd:c25:c25:94de:62d9/1282c19:dd:d9:dd:c25:c25:94de:62d9
2192c19:dd:d9:dd:c25:c25:94de:62da/1282c19:dd:d9:dd:c25:c25:94de:62da
2202c19:dd:d9:dd:c25:c25:94de:62db/1282c19:dd:d9:dd:c25:c25:94de:62db
2212c19:dd:d9:dd:c25:c25:94de:62dc/1282c19:dd:d9:dd:c25:c25:94de:62dc
2222c19:dd:d9:dd:c25:c25:94de:62dd/1282c19:dd:d9:dd:c25:c25:94de:62dd
2232c19:dd:d9:dd:c25:c25:94de:62de/1282c19:dd:d9:dd:c25:c25:94de:62de
2242c19:dd:d9:dd:c25:c25:94de:62df/1282c19:dd:d9:dd:c25:c25:94de:62df
2252c19:dd:d9:dd:c25:c25:94de:62e0/1282c19:dd:d9:dd:c25:c25:94de:62e0
2262c19:dd:d9:dd:c25:c25:94de:62e1/1282c19:dd:d9:dd:c25:c25:94de:62e1
2272c19:dd:d9:dd:c25:c25:94de:62e2/1282c19:dd:d9:dd:c25:c25:94de:62e2
2282c19:dd:d9:dd:c25:c25:94de:62e3/1282c19:dd:d9:dd:c25:c25:94de:62e3
2292c19:dd:d9:dd:c25:c25:94de:62e4/1282c19:dd:d9:dd:c25:c25:94de:62e4
2302c19:dd:d9:dd:c25:c25:94de:62e5/1282c19:dd:d9:dd:c25:c25:94de:62e5
2312c19:dd:d9:dd:c25:c25:94de:62e6/1282c19:dd:d9:dd:c25:c25:94de:62e6
2322c19:dd:d9:dd:c25:c25:94de:62e7/1282c19:dd:d9:dd:c25:c25:94de:62e7
2332c19:dd:d9:dd:c25:c25:94de:62e8/1282c19:dd:d9:dd:c25:c25:94de:62e8
2342c19:dd:d9:dd:c25:c25:94de:62e9/1282c19:dd:d9:dd:c25:c25:94de:62e9
2352c19:dd:d9:dd:c25:c25:94de:62ea/1282c19:dd:d9:dd:c25:c25:94de:62ea
2362c19:dd:d9:dd:c25:c25:94de:62eb/1282c19:dd:d9:dd:c25:c25:94de:62eb
2372c19:dd:d9:dd:c25:c25:94de:62ec/1282c19:dd:d9:dd:c25:c25:94de:62ec
2382c19:dd:d9:dd:c25:c25:94de:62ed/1282c19:dd:d9:dd:c25:c25:94de:62ed
2392c19:dd:d9:dd:c25:c25:94de:62ee/1282c19:dd:d9:dd:c25:c25:94de:62ee
2402c19:dd:d9:dd:c25:c25:94de:62ef/1282c19:dd:d9:dd:c25:c25:94de:62ef
2412c19:dd:d9:dd:c25:c25:94de:62f0/1282c19:dd:d9:dd:c25:c25:94de:62f0
2422c19:dd:d9:dd:c25:c25:94de:62f1/1282c19:dd:d9:dd:c25:c25:94de:62f1
2432c19:dd:d9:dd:c25:c25:94de:62f2/1282c19:dd:d9:dd:c25:c25:94de:62f2
2442c19:dd:d9:dd:c25:c25:94de:62f3/1282c19:dd:d9:dd:c25:c25:94de:62f3
2452c19:dd:d9:dd:c25:c25:94de:62f4/1282c19:dd:d9:dd:c25:c25:94de:62f4
2462c19:dd:d9:dd:c25:c25:94de:62f5/1282c19:dd:d9:dd:c25:c25:94de:62f5
2472c19:dd:d9:dd:c25:c25:94de:62f6/1282c19:dd:d9:dd:c25:c25:94de:62f6
2482c19:dd:d9:dd:c25:c25:94de:62f7/1282c19:dd:d9:dd:c25:c25:94de:62f7
2492c19:dd:d9:dd:c25:c25:94de:62f8/1282c19:dd:d9:dd:c25:c25:94de:62f8
2502c19:dd:d9:dd:c25:c25:94de:62f9/1282c19:dd:d9:dd:c25:c25:94de:62f9
2512c19:dd:d9:dd:c25:c25:94de:62fa/1282c19:dd:d9:dd:c25:c25:94de:62fa
2522c19:dd:d9:dd:c25:c25:94de:62fb/1282c19:dd:d9:dd:c25:c25:94de:62fb
2532c19:dd:d9:dd:c25:c25:94de:62fc/1282c19:dd:d9:dd:c25:c25:94de:62fc
2542c19:dd:d9:dd:c25:c25:94de:62fd/1282c19:dd:d9:dd:c25:c25:94de:62fd
2552c19:dd:d9:dd:c25:c25:94de:62fe/1282c19:dd:d9:dd:c25:c25:94de:62fe
2562c19:dd:d9:dd:c25:c25:94de:62ff/1282c19:dd:d9:dd:c25:c25:94de:62ff

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.