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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:e00a:c200/119
First address
2c19:dd:d9:dd:c25:c25:e00a:c200
Last address
2c19:dd:d9:dd:c25:c25:e00a:c3ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:e00a:c200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.c.a.0.0.e.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
3.c.a.0.0.e.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:e00a:c200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:e00a:c200/1272c19:dd:d9:dd:c25:c25:e00a:c201
22c19:dd:d9:dd:c25:c25:e00a:c202/1272c19:dd:d9:dd:c25:c25:e00a:c203
32c19:dd:d9:dd:c25:c25:e00a:c204/1272c19:dd:d9:dd:c25:c25:e00a:c205
42c19:dd:d9:dd:c25:c25:e00a:c206/1272c19:dd:d9:dd:c25:c25:e00a:c207
52c19:dd:d9:dd:c25:c25:e00a:c208/1272c19:dd:d9:dd:c25:c25:e00a:c209
62c19:dd:d9:dd:c25:c25:e00a:c20a/1272c19:dd:d9:dd:c25:c25:e00a:c20b
72c19:dd:d9:dd:c25:c25:e00a:c20c/1272c19:dd:d9:dd:c25:c25:e00a:c20d
82c19:dd:d9:dd:c25:c25:e00a:c20e/1272c19:dd:d9:dd:c25:c25:e00a:c20f
92c19:dd:d9:dd:c25:c25:e00a:c210/1272c19:dd:d9:dd:c25:c25:e00a:c211
102c19:dd:d9:dd:c25:c25:e00a:c212/1272c19:dd:d9:dd:c25:c25:e00a:c213
112c19:dd:d9:dd:c25:c25:e00a:c214/1272c19:dd:d9:dd:c25:c25:e00a:c215
122c19:dd:d9:dd:c25:c25:e00a:c216/1272c19:dd:d9:dd:c25:c25:e00a:c217
132c19:dd:d9:dd:c25:c25:e00a:c218/1272c19:dd:d9:dd:c25:c25:e00a:c219
142c19:dd:d9:dd:c25:c25:e00a:c21a/1272c19:dd:d9:dd:c25:c25:e00a:c21b
152c19:dd:d9:dd:c25:c25:e00a:c21c/1272c19:dd:d9:dd:c25:c25:e00a:c21d
162c19:dd:d9:dd:c25:c25:e00a:c21e/1272c19:dd:d9:dd:c25:c25:e00a:c21f
172c19:dd:d9:dd:c25:c25:e00a:c220/1272c19:dd:d9:dd:c25:c25:e00a:c221
182c19:dd:d9:dd:c25:c25:e00a:c222/1272c19:dd:d9:dd:c25:c25:e00a:c223
192c19:dd:d9:dd:c25:c25:e00a:c224/1272c19:dd:d9:dd:c25:c25:e00a:c225
202c19:dd:d9:dd:c25:c25:e00a:c226/1272c19:dd:d9:dd:c25:c25:e00a:c227
212c19:dd:d9:dd:c25:c25:e00a:c228/1272c19:dd:d9:dd:c25:c25:e00a:c229
222c19:dd:d9:dd:c25:c25:e00a:c22a/1272c19:dd:d9:dd:c25:c25:e00a:c22b
232c19:dd:d9:dd:c25:c25:e00a:c22c/1272c19:dd:d9:dd:c25:c25:e00a:c22d
242c19:dd:d9:dd:c25:c25:e00a:c22e/1272c19:dd:d9:dd:c25:c25:e00a:c22f
252c19:dd:d9:dd:c25:c25:e00a:c230/1272c19:dd:d9:dd:c25:c25:e00a:c231
262c19:dd:d9:dd:c25:c25:e00a:c232/1272c19:dd:d9:dd:c25:c25:e00a:c233
272c19:dd:d9:dd:c25:c25:e00a:c234/1272c19:dd:d9:dd:c25:c25:e00a:c235
282c19:dd:d9:dd:c25:c25:e00a:c236/1272c19:dd:d9:dd:c25:c25:e00a:c237
292c19:dd:d9:dd:c25:c25:e00a:c238/1272c19:dd:d9:dd:c25:c25:e00a:c239
302c19:dd:d9:dd:c25:c25:e00a:c23a/1272c19:dd:d9:dd:c25:c25:e00a:c23b
312c19:dd:d9:dd:c25:c25:e00a:c23c/1272c19:dd:d9:dd:c25:c25:e00a:c23d
322c19:dd:d9:dd:c25:c25:e00a:c23e/1272c19:dd:d9:dd:c25:c25:e00a:c23f
332c19:dd:d9:dd:c25:c25:e00a:c240/1272c19:dd:d9:dd:c25:c25:e00a:c241
342c19:dd:d9:dd:c25:c25:e00a:c242/1272c19:dd:d9:dd:c25:c25:e00a:c243
352c19:dd:d9:dd:c25:c25:e00a:c244/1272c19:dd:d9:dd:c25:c25:e00a:c245
362c19:dd:d9:dd:c25:c25:e00a:c246/1272c19:dd:d9:dd:c25:c25:e00a:c247
372c19:dd:d9:dd:c25:c25:e00a:c248/1272c19:dd:d9:dd:c25:c25:e00a:c249
382c19:dd:d9:dd:c25:c25:e00a:c24a/1272c19:dd:d9:dd:c25:c25:e00a:c24b
392c19:dd:d9:dd:c25:c25:e00a:c24c/1272c19:dd:d9:dd:c25:c25:e00a:c24d
402c19:dd:d9:dd:c25:c25:e00a:c24e/1272c19:dd:d9:dd:c25:c25:e00a:c24f
412c19:dd:d9:dd:c25:c25:e00a:c250/1272c19:dd:d9:dd:c25:c25:e00a:c251
422c19:dd:d9:dd:c25:c25:e00a:c252/1272c19:dd:d9:dd:c25:c25:e00a:c253
432c19:dd:d9:dd:c25:c25:e00a:c254/1272c19:dd:d9:dd:c25:c25:e00a:c255
442c19:dd:d9:dd:c25:c25:e00a:c256/1272c19:dd:d9:dd:c25:c25:e00a:c257
452c19:dd:d9:dd:c25:c25:e00a:c258/1272c19:dd:d9:dd:c25:c25:e00a:c259
462c19:dd:d9:dd:c25:c25:e00a:c25a/1272c19:dd:d9:dd:c25:c25:e00a:c25b
472c19:dd:d9:dd:c25:c25:e00a:c25c/1272c19:dd:d9:dd:c25:c25:e00a:c25d
482c19:dd:d9:dd:c25:c25:e00a:c25e/1272c19:dd:d9:dd:c25:c25:e00a:c25f
492c19:dd:d9:dd:c25:c25:e00a:c260/1272c19:dd:d9:dd:c25:c25:e00a:c261
502c19:dd:d9:dd:c25:c25:e00a:c262/1272c19:dd:d9:dd:c25:c25:e00a:c263
512c19:dd:d9:dd:c25:c25:e00a:c264/1272c19:dd:d9:dd:c25:c25:e00a:c265
522c19:dd:d9:dd:c25:c25:e00a:c266/1272c19:dd:d9:dd:c25:c25:e00a:c267
532c19:dd:d9:dd:c25:c25:e00a:c268/1272c19:dd:d9:dd:c25:c25:e00a:c269
542c19:dd:d9:dd:c25:c25:e00a:c26a/1272c19:dd:d9:dd:c25:c25:e00a:c26b
552c19:dd:d9:dd:c25:c25:e00a:c26c/1272c19:dd:d9:dd:c25:c25:e00a:c26d
562c19:dd:d9:dd:c25:c25:e00a:c26e/1272c19:dd:d9:dd:c25:c25:e00a:c26f
572c19:dd:d9:dd:c25:c25:e00a:c270/1272c19:dd:d9:dd:c25:c25:e00a:c271
582c19:dd:d9:dd:c25:c25:e00a:c272/1272c19:dd:d9:dd:c25:c25:e00a:c273
592c19:dd:d9:dd:c25:c25:e00a:c274/1272c19:dd:d9:dd:c25:c25:e00a:c275
602c19:dd:d9:dd:c25:c25:e00a:c276/1272c19:dd:d9:dd:c25:c25:e00a:c277
612c19:dd:d9:dd:c25:c25:e00a:c278/1272c19:dd:d9:dd:c25:c25:e00a:c279
622c19:dd:d9:dd:c25:c25:e00a:c27a/1272c19:dd:d9:dd:c25:c25:e00a:c27b
632c19:dd:d9:dd:c25:c25:e00a:c27c/1272c19:dd:d9:dd:c25:c25:e00a:c27d
642c19:dd:d9:dd:c25:c25:e00a:c27e/1272c19:dd:d9:dd:c25:c25:e00a:c27f
652c19:dd:d9:dd:c25:c25:e00a:c280/1272c19:dd:d9:dd:c25:c25:e00a:c281
662c19:dd:d9:dd:c25:c25:e00a:c282/1272c19:dd:d9:dd:c25:c25:e00a:c283
672c19:dd:d9:dd:c25:c25:e00a:c284/1272c19:dd:d9:dd:c25:c25:e00a:c285
682c19:dd:d9:dd:c25:c25:e00a:c286/1272c19:dd:d9:dd:c25:c25:e00a:c287
692c19:dd:d9:dd:c25:c25:e00a:c288/1272c19:dd:d9:dd:c25:c25:e00a:c289
702c19:dd:d9:dd:c25:c25:e00a:c28a/1272c19:dd:d9:dd:c25:c25:e00a:c28b
712c19:dd:d9:dd:c25:c25:e00a:c28c/1272c19:dd:d9:dd:c25:c25:e00a:c28d
722c19:dd:d9:dd:c25:c25:e00a:c28e/1272c19:dd:d9:dd:c25:c25:e00a:c28f
732c19:dd:d9:dd:c25:c25:e00a:c290/1272c19:dd:d9:dd:c25:c25:e00a:c291
742c19:dd:d9:dd:c25:c25:e00a:c292/1272c19:dd:d9:dd:c25:c25:e00a:c293
752c19:dd:d9:dd:c25:c25:e00a:c294/1272c19:dd:d9:dd:c25:c25:e00a:c295
762c19:dd:d9:dd:c25:c25:e00a:c296/1272c19:dd:d9:dd:c25:c25:e00a:c297
772c19:dd:d9:dd:c25:c25:e00a:c298/1272c19:dd:d9:dd:c25:c25:e00a:c299
782c19:dd:d9:dd:c25:c25:e00a:c29a/1272c19:dd:d9:dd:c25:c25:e00a:c29b
792c19:dd:d9:dd:c25:c25:e00a:c29c/1272c19:dd:d9:dd:c25:c25:e00a:c29d
802c19:dd:d9:dd:c25:c25:e00a:c29e/1272c19:dd:d9:dd:c25:c25:e00a:c29f
812c19:dd:d9:dd:c25:c25:e00a:c2a0/1272c19:dd:d9:dd:c25:c25:e00a:c2a1
822c19:dd:d9:dd:c25:c25:e00a:c2a2/1272c19:dd:d9:dd:c25:c25:e00a:c2a3
832c19:dd:d9:dd:c25:c25:e00a:c2a4/1272c19:dd:d9:dd:c25:c25:e00a:c2a5
842c19:dd:d9:dd:c25:c25:e00a:c2a6/1272c19:dd:d9:dd:c25:c25:e00a:c2a7
852c19:dd:d9:dd:c25:c25:e00a:c2a8/1272c19:dd:d9:dd:c25:c25:e00a:c2a9
862c19:dd:d9:dd:c25:c25:e00a:c2aa/1272c19:dd:d9:dd:c25:c25:e00a:c2ab
872c19:dd:d9:dd:c25:c25:e00a:c2ac/1272c19:dd:d9:dd:c25:c25:e00a:c2ad
882c19:dd:d9:dd:c25:c25:e00a:c2ae/1272c19:dd:d9:dd:c25:c25:e00a:c2af
892c19:dd:d9:dd:c25:c25:e00a:c2b0/1272c19:dd:d9:dd:c25:c25:e00a:c2b1
902c19:dd:d9:dd:c25:c25:e00a:c2b2/1272c19:dd:d9:dd:c25:c25:e00a:c2b3
912c19:dd:d9:dd:c25:c25:e00a:c2b4/1272c19:dd:d9:dd:c25:c25:e00a:c2b5
922c19:dd:d9:dd:c25:c25:e00a:c2b6/1272c19:dd:d9:dd:c25:c25:e00a:c2b7
932c19:dd:d9:dd:c25:c25:e00a:c2b8/1272c19:dd:d9:dd:c25:c25:e00a:c2b9
942c19:dd:d9:dd:c25:c25:e00a:c2ba/1272c19:dd:d9:dd:c25:c25:e00a:c2bb
952c19:dd:d9:dd:c25:c25:e00a:c2bc/1272c19:dd:d9:dd:c25:c25:e00a:c2bd
962c19:dd:d9:dd:c25:c25:e00a:c2be/1272c19:dd:d9:dd:c25:c25:e00a:c2bf
972c19:dd:d9:dd:c25:c25:e00a:c2c0/1272c19:dd:d9:dd:c25:c25:e00a:c2c1
982c19:dd:d9:dd:c25:c25:e00a:c2c2/1272c19:dd:d9:dd:c25:c25:e00a:c2c3
992c19:dd:d9:dd:c25:c25:e00a:c2c4/1272c19:dd:d9:dd:c25:c25:e00a:c2c5
1002c19:dd:d9:dd:c25:c25:e00a:c2c6/1272c19:dd:d9:dd:c25:c25:e00a:c2c7
1012c19:dd:d9:dd:c25:c25:e00a:c2c8/1272c19:dd:d9:dd:c25:c25:e00a:c2c9
1022c19:dd:d9:dd:c25:c25:e00a:c2ca/1272c19:dd:d9:dd:c25:c25:e00a:c2cb
1032c19:dd:d9:dd:c25:c25:e00a:c2cc/1272c19:dd:d9:dd:c25:c25:e00a:c2cd
1042c19:dd:d9:dd:c25:c25:e00a:c2ce/1272c19:dd:d9:dd:c25:c25:e00a:c2cf
1052c19:dd:d9:dd:c25:c25:e00a:c2d0/1272c19:dd:d9:dd:c25:c25:e00a:c2d1
1062c19:dd:d9:dd:c25:c25:e00a:c2d2/1272c19:dd:d9:dd:c25:c25:e00a:c2d3
1072c19:dd:d9:dd:c25:c25:e00a:c2d4/1272c19:dd:d9:dd:c25:c25:e00a:c2d5
1082c19:dd:d9:dd:c25:c25:e00a:c2d6/1272c19:dd:d9:dd:c25:c25:e00a:c2d7
1092c19:dd:d9:dd:c25:c25:e00a:c2d8/1272c19:dd:d9:dd:c25:c25:e00a:c2d9
1102c19:dd:d9:dd:c25:c25:e00a:c2da/1272c19:dd:d9:dd:c25:c25:e00a:c2db
1112c19:dd:d9:dd:c25:c25:e00a:c2dc/1272c19:dd:d9:dd:c25:c25:e00a:c2dd
1122c19:dd:d9:dd:c25:c25:e00a:c2de/1272c19:dd:d9:dd:c25:c25:e00a:c2df
1132c19:dd:d9:dd:c25:c25:e00a:c2e0/1272c19:dd:d9:dd:c25:c25:e00a:c2e1
1142c19:dd:d9:dd:c25:c25:e00a:c2e2/1272c19:dd:d9:dd:c25:c25:e00a:c2e3
1152c19:dd:d9:dd:c25:c25:e00a:c2e4/1272c19:dd:d9:dd:c25:c25:e00a:c2e5
1162c19:dd:d9:dd:c25:c25:e00a:c2e6/1272c19:dd:d9:dd:c25:c25:e00a:c2e7
1172c19:dd:d9:dd:c25:c25:e00a:c2e8/1272c19:dd:d9:dd:c25:c25:e00a:c2e9
1182c19:dd:d9:dd:c25:c25:e00a:c2ea/1272c19:dd:d9:dd:c25:c25:e00a:c2eb
1192c19:dd:d9:dd:c25:c25:e00a:c2ec/1272c19:dd:d9:dd:c25:c25:e00a:c2ed
1202c19:dd:d9:dd:c25:c25:e00a:c2ee/1272c19:dd:d9:dd:c25:c25:e00a:c2ef
1212c19:dd:d9:dd:c25:c25:e00a:c2f0/1272c19:dd:d9:dd:c25:c25:e00a:c2f1
1222c19:dd:d9:dd:c25:c25:e00a:c2f2/1272c19:dd:d9:dd:c25:c25:e00a:c2f3
1232c19:dd:d9:dd:c25:c25:e00a:c2f4/1272c19:dd:d9:dd:c25:c25:e00a:c2f5
1242c19:dd:d9:dd:c25:c25:e00a:c2f6/1272c19:dd:d9:dd:c25:c25:e00a:c2f7
1252c19:dd:d9:dd:c25:c25:e00a:c2f8/1272c19:dd:d9:dd:c25:c25:e00a:c2f9
1262c19:dd:d9:dd:c25:c25:e00a:c2fa/1272c19:dd:d9:dd:c25:c25:e00a:c2fb
1272c19:dd:d9:dd:c25:c25:e00a:c2fc/1272c19:dd:d9:dd:c25:c25:e00a:c2fd
1282c19:dd:d9:dd:c25:c25:e00a:c2fe/1272c19:dd:d9:dd:c25:c25:e00a:c2ff
1292c19:dd:d9:dd:c25:c25:e00a:c300/1272c19:dd:d9:dd:c25:c25:e00a:c301
1302c19:dd:d9:dd:c25:c25:e00a:c302/1272c19:dd:d9:dd:c25:c25:e00a:c303
1312c19:dd:d9:dd:c25:c25:e00a:c304/1272c19:dd:d9:dd:c25:c25:e00a:c305
1322c19:dd:d9:dd:c25:c25:e00a:c306/1272c19:dd:d9:dd:c25:c25:e00a:c307
1332c19:dd:d9:dd:c25:c25:e00a:c308/1272c19:dd:d9:dd:c25:c25:e00a:c309
1342c19:dd:d9:dd:c25:c25:e00a:c30a/1272c19:dd:d9:dd:c25:c25:e00a:c30b
1352c19:dd:d9:dd:c25:c25:e00a:c30c/1272c19:dd:d9:dd:c25:c25:e00a:c30d
1362c19:dd:d9:dd:c25:c25:e00a:c30e/1272c19:dd:d9:dd:c25:c25:e00a:c30f
1372c19:dd:d9:dd:c25:c25:e00a:c310/1272c19:dd:d9:dd:c25:c25:e00a:c311
1382c19:dd:d9:dd:c25:c25:e00a:c312/1272c19:dd:d9:dd:c25:c25:e00a:c313
1392c19:dd:d9:dd:c25:c25:e00a:c314/1272c19:dd:d9:dd:c25:c25:e00a:c315
1402c19:dd:d9:dd:c25:c25:e00a:c316/1272c19:dd:d9:dd:c25:c25:e00a:c317
1412c19:dd:d9:dd:c25:c25:e00a:c318/1272c19:dd:d9:dd:c25:c25:e00a:c319
1422c19:dd:d9:dd:c25:c25:e00a:c31a/1272c19:dd:d9:dd:c25:c25:e00a:c31b
1432c19:dd:d9:dd:c25:c25:e00a:c31c/1272c19:dd:d9:dd:c25:c25:e00a:c31d
1442c19:dd:d9:dd:c25:c25:e00a:c31e/1272c19:dd:d9:dd:c25:c25:e00a:c31f
1452c19:dd:d9:dd:c25:c25:e00a:c320/1272c19:dd:d9:dd:c25:c25:e00a:c321
1462c19:dd:d9:dd:c25:c25:e00a:c322/1272c19:dd:d9:dd:c25:c25:e00a:c323
1472c19:dd:d9:dd:c25:c25:e00a:c324/1272c19:dd:d9:dd:c25:c25:e00a:c325
1482c19:dd:d9:dd:c25:c25:e00a:c326/1272c19:dd:d9:dd:c25:c25:e00a:c327
1492c19:dd:d9:dd:c25:c25:e00a:c328/1272c19:dd:d9:dd:c25:c25:e00a:c329
1502c19:dd:d9:dd:c25:c25:e00a:c32a/1272c19:dd:d9:dd:c25:c25:e00a:c32b
1512c19:dd:d9:dd:c25:c25:e00a:c32c/1272c19:dd:d9:dd:c25:c25:e00a:c32d
1522c19:dd:d9:dd:c25:c25:e00a:c32e/1272c19:dd:d9:dd:c25:c25:e00a:c32f
1532c19:dd:d9:dd:c25:c25:e00a:c330/1272c19:dd:d9:dd:c25:c25:e00a:c331
1542c19:dd:d9:dd:c25:c25:e00a:c332/1272c19:dd:d9:dd:c25:c25:e00a:c333
1552c19:dd:d9:dd:c25:c25:e00a:c334/1272c19:dd:d9:dd:c25:c25:e00a:c335
1562c19:dd:d9:dd:c25:c25:e00a:c336/1272c19:dd:d9:dd:c25:c25:e00a:c337
1572c19:dd:d9:dd:c25:c25:e00a:c338/1272c19:dd:d9:dd:c25:c25:e00a:c339
1582c19:dd:d9:dd:c25:c25:e00a:c33a/1272c19:dd:d9:dd:c25:c25:e00a:c33b
1592c19:dd:d9:dd:c25:c25:e00a:c33c/1272c19:dd:d9:dd:c25:c25:e00a:c33d
1602c19:dd:d9:dd:c25:c25:e00a:c33e/1272c19:dd:d9:dd:c25:c25:e00a:c33f
1612c19:dd:d9:dd:c25:c25:e00a:c340/1272c19:dd:d9:dd:c25:c25:e00a:c341
1622c19:dd:d9:dd:c25:c25:e00a:c342/1272c19:dd:d9:dd:c25:c25:e00a:c343
1632c19:dd:d9:dd:c25:c25:e00a:c344/1272c19:dd:d9:dd:c25:c25:e00a:c345
1642c19:dd:d9:dd:c25:c25:e00a:c346/1272c19:dd:d9:dd:c25:c25:e00a:c347
1652c19:dd:d9:dd:c25:c25:e00a:c348/1272c19:dd:d9:dd:c25:c25:e00a:c349
1662c19:dd:d9:dd:c25:c25:e00a:c34a/1272c19:dd:d9:dd:c25:c25:e00a:c34b
1672c19:dd:d9:dd:c25:c25:e00a:c34c/1272c19:dd:d9:dd:c25:c25:e00a:c34d
1682c19:dd:d9:dd:c25:c25:e00a:c34e/1272c19:dd:d9:dd:c25:c25:e00a:c34f
1692c19:dd:d9:dd:c25:c25:e00a:c350/1272c19:dd:d9:dd:c25:c25:e00a:c351
1702c19:dd:d9:dd:c25:c25:e00a:c352/1272c19:dd:d9:dd:c25:c25:e00a:c353
1712c19:dd:d9:dd:c25:c25:e00a:c354/1272c19:dd:d9:dd:c25:c25:e00a:c355
1722c19:dd:d9:dd:c25:c25:e00a:c356/1272c19:dd:d9:dd:c25:c25:e00a:c357
1732c19:dd:d9:dd:c25:c25:e00a:c358/1272c19:dd:d9:dd:c25:c25:e00a:c359
1742c19:dd:d9:dd:c25:c25:e00a:c35a/1272c19:dd:d9:dd:c25:c25:e00a:c35b
1752c19:dd:d9:dd:c25:c25:e00a:c35c/1272c19:dd:d9:dd:c25:c25:e00a:c35d
1762c19:dd:d9:dd:c25:c25:e00a:c35e/1272c19:dd:d9:dd:c25:c25:e00a:c35f
1772c19:dd:d9:dd:c25:c25:e00a:c360/1272c19:dd:d9:dd:c25:c25:e00a:c361
1782c19:dd:d9:dd:c25:c25:e00a:c362/1272c19:dd:d9:dd:c25:c25:e00a:c363
1792c19:dd:d9:dd:c25:c25:e00a:c364/1272c19:dd:d9:dd:c25:c25:e00a:c365
1802c19:dd:d9:dd:c25:c25:e00a:c366/1272c19:dd:d9:dd:c25:c25:e00a:c367
1812c19:dd:d9:dd:c25:c25:e00a:c368/1272c19:dd:d9:dd:c25:c25:e00a:c369
1822c19:dd:d9:dd:c25:c25:e00a:c36a/1272c19:dd:d9:dd:c25:c25:e00a:c36b
1832c19:dd:d9:dd:c25:c25:e00a:c36c/1272c19:dd:d9:dd:c25:c25:e00a:c36d
1842c19:dd:d9:dd:c25:c25:e00a:c36e/1272c19:dd:d9:dd:c25:c25:e00a:c36f
1852c19:dd:d9:dd:c25:c25:e00a:c370/1272c19:dd:d9:dd:c25:c25:e00a:c371
1862c19:dd:d9:dd:c25:c25:e00a:c372/1272c19:dd:d9:dd:c25:c25:e00a:c373
1872c19:dd:d9:dd:c25:c25:e00a:c374/1272c19:dd:d9:dd:c25:c25:e00a:c375
1882c19:dd:d9:dd:c25:c25:e00a:c376/1272c19:dd:d9:dd:c25:c25:e00a:c377
1892c19:dd:d9:dd:c25:c25:e00a:c378/1272c19:dd:d9:dd:c25:c25:e00a:c379
1902c19:dd:d9:dd:c25:c25:e00a:c37a/1272c19:dd:d9:dd:c25:c25:e00a:c37b
1912c19:dd:d9:dd:c25:c25:e00a:c37c/1272c19:dd:d9:dd:c25:c25:e00a:c37d
1922c19:dd:d9:dd:c25:c25:e00a:c37e/1272c19:dd:d9:dd:c25:c25:e00a:c37f
1932c19:dd:d9:dd:c25:c25:e00a:c380/1272c19:dd:d9:dd:c25:c25:e00a:c381
1942c19:dd:d9:dd:c25:c25:e00a:c382/1272c19:dd:d9:dd:c25:c25:e00a:c383
1952c19:dd:d9:dd:c25:c25:e00a:c384/1272c19:dd:d9:dd:c25:c25:e00a:c385
1962c19:dd:d9:dd:c25:c25:e00a:c386/1272c19:dd:d9:dd:c25:c25:e00a:c387
1972c19:dd:d9:dd:c25:c25:e00a:c388/1272c19:dd:d9:dd:c25:c25:e00a:c389
1982c19:dd:d9:dd:c25:c25:e00a:c38a/1272c19:dd:d9:dd:c25:c25:e00a:c38b
1992c19:dd:d9:dd:c25:c25:e00a:c38c/1272c19:dd:d9:dd:c25:c25:e00a:c38d
2002c19:dd:d9:dd:c25:c25:e00a:c38e/1272c19:dd:d9:dd:c25:c25:e00a:c38f
2012c19:dd:d9:dd:c25:c25:e00a:c390/1272c19:dd:d9:dd:c25:c25:e00a:c391
2022c19:dd:d9:dd:c25:c25:e00a:c392/1272c19:dd:d9:dd:c25:c25:e00a:c393
2032c19:dd:d9:dd:c25:c25:e00a:c394/1272c19:dd:d9:dd:c25:c25:e00a:c395
2042c19:dd:d9:dd:c25:c25:e00a:c396/1272c19:dd:d9:dd:c25:c25:e00a:c397
2052c19:dd:d9:dd:c25:c25:e00a:c398/1272c19:dd:d9:dd:c25:c25:e00a:c399
2062c19:dd:d9:dd:c25:c25:e00a:c39a/1272c19:dd:d9:dd:c25:c25:e00a:c39b
2072c19:dd:d9:dd:c25:c25:e00a:c39c/1272c19:dd:d9:dd:c25:c25:e00a:c39d
2082c19:dd:d9:dd:c25:c25:e00a:c39e/1272c19:dd:d9:dd:c25:c25:e00a:c39f
2092c19:dd:d9:dd:c25:c25:e00a:c3a0/1272c19:dd:d9:dd:c25:c25:e00a:c3a1
2102c19:dd:d9:dd:c25:c25:e00a:c3a2/1272c19:dd:d9:dd:c25:c25:e00a:c3a3
2112c19:dd:d9:dd:c25:c25:e00a:c3a4/1272c19:dd:d9:dd:c25:c25:e00a:c3a5
2122c19:dd:d9:dd:c25:c25:e00a:c3a6/1272c19:dd:d9:dd:c25:c25:e00a:c3a7
2132c19:dd:d9:dd:c25:c25:e00a:c3a8/1272c19:dd:d9:dd:c25:c25:e00a:c3a9
2142c19:dd:d9:dd:c25:c25:e00a:c3aa/1272c19:dd:d9:dd:c25:c25:e00a:c3ab
2152c19:dd:d9:dd:c25:c25:e00a:c3ac/1272c19:dd:d9:dd:c25:c25:e00a:c3ad
2162c19:dd:d9:dd:c25:c25:e00a:c3ae/1272c19:dd:d9:dd:c25:c25:e00a:c3af
2172c19:dd:d9:dd:c25:c25:e00a:c3b0/1272c19:dd:d9:dd:c25:c25:e00a:c3b1
2182c19:dd:d9:dd:c25:c25:e00a:c3b2/1272c19:dd:d9:dd:c25:c25:e00a:c3b3
2192c19:dd:d9:dd:c25:c25:e00a:c3b4/1272c19:dd:d9:dd:c25:c25:e00a:c3b5
2202c19:dd:d9:dd:c25:c25:e00a:c3b6/1272c19:dd:d9:dd:c25:c25:e00a:c3b7
2212c19:dd:d9:dd:c25:c25:e00a:c3b8/1272c19:dd:d9:dd:c25:c25:e00a:c3b9
2222c19:dd:d9:dd:c25:c25:e00a:c3ba/1272c19:dd:d9:dd:c25:c25:e00a:c3bb
2232c19:dd:d9:dd:c25:c25:e00a:c3bc/1272c19:dd:d9:dd:c25:c25:e00a:c3bd
2242c19:dd:d9:dd:c25:c25:e00a:c3be/1272c19:dd:d9:dd:c25:c25:e00a:c3bf
2252c19:dd:d9:dd:c25:c25:e00a:c3c0/1272c19:dd:d9:dd:c25:c25:e00a:c3c1
2262c19:dd:d9:dd:c25:c25:e00a:c3c2/1272c19:dd:d9:dd:c25:c25:e00a:c3c3
2272c19:dd:d9:dd:c25:c25:e00a:c3c4/1272c19:dd:d9:dd:c25:c25:e00a:c3c5
2282c19:dd:d9:dd:c25:c25:e00a:c3c6/1272c19:dd:d9:dd:c25:c25:e00a:c3c7
2292c19:dd:d9:dd:c25:c25:e00a:c3c8/1272c19:dd:d9:dd:c25:c25:e00a:c3c9
2302c19:dd:d9:dd:c25:c25:e00a:c3ca/1272c19:dd:d9:dd:c25:c25:e00a:c3cb
2312c19:dd:d9:dd:c25:c25:e00a:c3cc/1272c19:dd:d9:dd:c25:c25:e00a:c3cd
2322c19:dd:d9:dd:c25:c25:e00a:c3ce/1272c19:dd:d9:dd:c25:c25:e00a:c3cf
2332c19:dd:d9:dd:c25:c25:e00a:c3d0/1272c19:dd:d9:dd:c25:c25:e00a:c3d1
2342c19:dd:d9:dd:c25:c25:e00a:c3d2/1272c19:dd:d9:dd:c25:c25:e00a:c3d3
2352c19:dd:d9:dd:c25:c25:e00a:c3d4/1272c19:dd:d9:dd:c25:c25:e00a:c3d5
2362c19:dd:d9:dd:c25:c25:e00a:c3d6/1272c19:dd:d9:dd:c25:c25:e00a:c3d7
2372c19:dd:d9:dd:c25:c25:e00a:c3d8/1272c19:dd:d9:dd:c25:c25:e00a:c3d9
2382c19:dd:d9:dd:c25:c25:e00a:c3da/1272c19:dd:d9:dd:c25:c25:e00a:c3db
2392c19:dd:d9:dd:c25:c25:e00a:c3dc/1272c19:dd:d9:dd:c25:c25:e00a:c3dd
2402c19:dd:d9:dd:c25:c25:e00a:c3de/1272c19:dd:d9:dd:c25:c25:e00a:c3df
2412c19:dd:d9:dd:c25:c25:e00a:c3e0/1272c19:dd:d9:dd:c25:c25:e00a:c3e1
2422c19:dd:d9:dd:c25:c25:e00a:c3e2/1272c19:dd:d9:dd:c25:c25:e00a:c3e3
2432c19:dd:d9:dd:c25:c25:e00a:c3e4/1272c19:dd:d9:dd:c25:c25:e00a:c3e5
2442c19:dd:d9:dd:c25:c25:e00a:c3e6/1272c19:dd:d9:dd:c25:c25:e00a:c3e7
2452c19:dd:d9:dd:c25:c25:e00a:c3e8/1272c19:dd:d9:dd:c25:c25:e00a:c3e9
2462c19:dd:d9:dd:c25:c25:e00a:c3ea/1272c19:dd:d9:dd:c25:c25:e00a:c3eb
2472c19:dd:d9:dd:c25:c25:e00a:c3ec/1272c19:dd:d9:dd:c25:c25:e00a:c3ed
2482c19:dd:d9:dd:c25:c25:e00a:c3ee/1272c19:dd:d9:dd:c25:c25:e00a:c3ef
2492c19:dd:d9:dd:c25:c25:e00a:c3f0/1272c19:dd:d9:dd:c25:c25:e00a:c3f1
2502c19:dd:d9:dd:c25:c25:e00a:c3f2/1272c19:dd:d9:dd:c25:c25:e00a:c3f3
2512c19:dd:d9:dd:c25:c25:e00a:c3f4/1272c19:dd:d9:dd:c25:c25:e00a:c3f5
2522c19:dd:d9:dd:c25:c25:e00a:c3f6/1272c19:dd:d9:dd:c25:c25:e00a:c3f7
2532c19:dd:d9:dd:c25:c25:e00a:c3f8/1272c19:dd:d9:dd:c25:c25:e00a:c3f9
2542c19:dd:d9:dd:c25:c25:e00a:c3fa/1272c19:dd:d9:dd:c25:c25:e00a:c3fb
2552c19:dd:d9:dd:c25:c25:e00a:c3fc/1272c19:dd:d9:dd:c25:c25:e00a:c3fd
2562c19:dd:d9:dd:c25:c25:e00a:c3fe/1272c19:dd:d9:dd:c25:c25:e00a:c3ff

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.