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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:c25:94de:200/119
First address
2c19:dd:d9:dd:c25:c25:94de:200
Last address
2c19:dd:d9:dd:c25:c25:94de:3ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:0200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.0.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
3.0.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
/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:c25:94de:200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:200/1272c19:dd:d9:dd:c25:c25:94de:201
22c19:dd:d9:dd:c25:c25:94de:202/1272c19:dd:d9:dd:c25:c25:94de:203
32c19:dd:d9:dd:c25:c25:94de:204/1272c19:dd:d9:dd:c25:c25:94de:205
42c19:dd:d9:dd:c25:c25:94de:206/1272c19:dd:d9:dd:c25:c25:94de:207
52c19:dd:d9:dd:c25:c25:94de:208/1272c19:dd:d9:dd:c25:c25:94de:209
62c19:dd:d9:dd:c25:c25:94de:20a/1272c19:dd:d9:dd:c25:c25:94de:20b
72c19:dd:d9:dd:c25:c25:94de:20c/1272c19:dd:d9:dd:c25:c25:94de:20d
82c19:dd:d9:dd:c25:c25:94de:20e/1272c19:dd:d9:dd:c25:c25:94de:20f
92c19:dd:d9:dd:c25:c25:94de:210/1272c19:dd:d9:dd:c25:c25:94de:211
102c19:dd:d9:dd:c25:c25:94de:212/1272c19:dd:d9:dd:c25:c25:94de:213
112c19:dd:d9:dd:c25:c25:94de:214/1272c19:dd:d9:dd:c25:c25:94de:215
122c19:dd:d9:dd:c25:c25:94de:216/1272c19:dd:d9:dd:c25:c25:94de:217
132c19:dd:d9:dd:c25:c25:94de:218/1272c19:dd:d9:dd:c25:c25:94de:219
142c19:dd:d9:dd:c25:c25:94de:21a/1272c19:dd:d9:dd:c25:c25:94de:21b
152c19:dd:d9:dd:c25:c25:94de:21c/1272c19:dd:d9:dd:c25:c25:94de:21d
162c19:dd:d9:dd:c25:c25:94de:21e/1272c19:dd:d9:dd:c25:c25:94de:21f
172c19:dd:d9:dd:c25:c25:94de:220/1272c19:dd:d9:dd:c25:c25:94de:221
182c19:dd:d9:dd:c25:c25:94de:222/1272c19:dd:d9:dd:c25:c25:94de:223
192c19:dd:d9:dd:c25:c25:94de:224/1272c19:dd:d9:dd:c25:c25:94de:225
202c19:dd:d9:dd:c25:c25:94de:226/1272c19:dd:d9:dd:c25:c25:94de:227
212c19:dd:d9:dd:c25:c25:94de:228/1272c19:dd:d9:dd:c25:c25:94de:229
222c19:dd:d9:dd:c25:c25:94de:22a/1272c19:dd:d9:dd:c25:c25:94de:22b
232c19:dd:d9:dd:c25:c25:94de:22c/1272c19:dd:d9:dd:c25:c25:94de:22d
242c19:dd:d9:dd:c25:c25:94de:22e/1272c19:dd:d9:dd:c25:c25:94de:22f
252c19:dd:d9:dd:c25:c25:94de:230/1272c19:dd:d9:dd:c25:c25:94de:231
262c19:dd:d9:dd:c25:c25:94de:232/1272c19:dd:d9:dd:c25:c25:94de:233
272c19:dd:d9:dd:c25:c25:94de:234/1272c19:dd:d9:dd:c25:c25:94de:235
282c19:dd:d9:dd:c25:c25:94de:236/1272c19:dd:d9:dd:c25:c25:94de:237
292c19:dd:d9:dd:c25:c25:94de:238/1272c19:dd:d9:dd:c25:c25:94de:239
302c19:dd:d9:dd:c25:c25:94de:23a/1272c19:dd:d9:dd:c25:c25:94de:23b
312c19:dd:d9:dd:c25:c25:94de:23c/1272c19:dd:d9:dd:c25:c25:94de:23d
322c19:dd:d9:dd:c25:c25:94de:23e/1272c19:dd:d9:dd:c25:c25:94de:23f
332c19:dd:d9:dd:c25:c25:94de:240/1272c19:dd:d9:dd:c25:c25:94de:241
342c19:dd:d9:dd:c25:c25:94de:242/1272c19:dd:d9:dd:c25:c25:94de:243
352c19:dd:d9:dd:c25:c25:94de:244/1272c19:dd:d9:dd:c25:c25:94de:245
362c19:dd:d9:dd:c25:c25:94de:246/1272c19:dd:d9:dd:c25:c25:94de:247
372c19:dd:d9:dd:c25:c25:94de:248/1272c19:dd:d9:dd:c25:c25:94de:249
382c19:dd:d9:dd:c25:c25:94de:24a/1272c19:dd:d9:dd:c25:c25:94de:24b
392c19:dd:d9:dd:c25:c25:94de:24c/1272c19:dd:d9:dd:c25:c25:94de:24d
402c19:dd:d9:dd:c25:c25:94de:24e/1272c19:dd:d9:dd:c25:c25:94de:24f
412c19:dd:d9:dd:c25:c25:94de:250/1272c19:dd:d9:dd:c25:c25:94de:251
422c19:dd:d9:dd:c25:c25:94de:252/1272c19:dd:d9:dd:c25:c25:94de:253
432c19:dd:d9:dd:c25:c25:94de:254/1272c19:dd:d9:dd:c25:c25:94de:255
442c19:dd:d9:dd:c25:c25:94de:256/1272c19:dd:d9:dd:c25:c25:94de:257
452c19:dd:d9:dd:c25:c25:94de:258/1272c19:dd:d9:dd:c25:c25:94de:259
462c19:dd:d9:dd:c25:c25:94de:25a/1272c19:dd:d9:dd:c25:c25:94de:25b
472c19:dd:d9:dd:c25:c25:94de:25c/1272c19:dd:d9:dd:c25:c25:94de:25d
482c19:dd:d9:dd:c25:c25:94de:25e/1272c19:dd:d9:dd:c25:c25:94de:25f
492c19:dd:d9:dd:c25:c25:94de:260/1272c19:dd:d9:dd:c25:c25:94de:261
502c19:dd:d9:dd:c25:c25:94de:262/1272c19:dd:d9:dd:c25:c25:94de:263
512c19:dd:d9:dd:c25:c25:94de:264/1272c19:dd:d9:dd:c25:c25:94de:265
522c19:dd:d9:dd:c25:c25:94de:266/1272c19:dd:d9:dd:c25:c25:94de:267
532c19:dd:d9:dd:c25:c25:94de:268/1272c19:dd:d9:dd:c25:c25:94de:269
542c19:dd:d9:dd:c25:c25:94de:26a/1272c19:dd:d9:dd:c25:c25:94de:26b
552c19:dd:d9:dd:c25:c25:94de:26c/1272c19:dd:d9:dd:c25:c25:94de:26d
562c19:dd:d9:dd:c25:c25:94de:26e/1272c19:dd:d9:dd:c25:c25:94de:26f
572c19:dd:d9:dd:c25:c25:94de:270/1272c19:dd:d9:dd:c25:c25:94de:271
582c19:dd:d9:dd:c25:c25:94de:272/1272c19:dd:d9:dd:c25:c25:94de:273
592c19:dd:d9:dd:c25:c25:94de:274/1272c19:dd:d9:dd:c25:c25:94de:275
602c19:dd:d9:dd:c25:c25:94de:276/1272c19:dd:d9:dd:c25:c25:94de:277
612c19:dd:d9:dd:c25:c25:94de:278/1272c19:dd:d9:dd:c25:c25:94de:279
622c19:dd:d9:dd:c25:c25:94de:27a/1272c19:dd:d9:dd:c25:c25:94de:27b
632c19:dd:d9:dd:c25:c25:94de:27c/1272c19:dd:d9:dd:c25:c25:94de:27d
642c19:dd:d9:dd:c25:c25:94de:27e/1272c19:dd:d9:dd:c25:c25:94de:27f
652c19:dd:d9:dd:c25:c25:94de:280/1272c19:dd:d9:dd:c25:c25:94de:281
662c19:dd:d9:dd:c25:c25:94de:282/1272c19:dd:d9:dd:c25:c25:94de:283
672c19:dd:d9:dd:c25:c25:94de:284/1272c19:dd:d9:dd:c25:c25:94de:285
682c19:dd:d9:dd:c25:c25:94de:286/1272c19:dd:d9:dd:c25:c25:94de:287
692c19:dd:d9:dd:c25:c25:94de:288/1272c19:dd:d9:dd:c25:c25:94de:289
702c19:dd:d9:dd:c25:c25:94de:28a/1272c19:dd:d9:dd:c25:c25:94de:28b
712c19:dd:d9:dd:c25:c25:94de:28c/1272c19:dd:d9:dd:c25:c25:94de:28d
722c19:dd:d9:dd:c25:c25:94de:28e/1272c19:dd:d9:dd:c25:c25:94de:28f
732c19:dd:d9:dd:c25:c25:94de:290/1272c19:dd:d9:dd:c25:c25:94de:291
742c19:dd:d9:dd:c25:c25:94de:292/1272c19:dd:d9:dd:c25:c25:94de:293
752c19:dd:d9:dd:c25:c25:94de:294/1272c19:dd:d9:dd:c25:c25:94de:295
762c19:dd:d9:dd:c25:c25:94de:296/1272c19:dd:d9:dd:c25:c25:94de:297
772c19:dd:d9:dd:c25:c25:94de:298/1272c19:dd:d9:dd:c25:c25:94de:299
782c19:dd:d9:dd:c25:c25:94de:29a/1272c19:dd:d9:dd:c25:c25:94de:29b
792c19:dd:d9:dd:c25:c25:94de:29c/1272c19:dd:d9:dd:c25:c25:94de:29d
802c19:dd:d9:dd:c25:c25:94de:29e/1272c19:dd:d9:dd:c25:c25:94de:29f
812c19:dd:d9:dd:c25:c25:94de:2a0/1272c19:dd:d9:dd:c25:c25:94de:2a1
822c19:dd:d9:dd:c25:c25:94de:2a2/1272c19:dd:d9:dd:c25:c25:94de:2a3
832c19:dd:d9:dd:c25:c25:94de:2a4/1272c19:dd:d9:dd:c25:c25:94de:2a5
842c19:dd:d9:dd:c25:c25:94de:2a6/1272c19:dd:d9:dd:c25:c25:94de:2a7
852c19:dd:d9:dd:c25:c25:94de:2a8/1272c19:dd:d9:dd:c25:c25:94de:2a9
862c19:dd:d9:dd:c25:c25:94de:2aa/1272c19:dd:d9:dd:c25:c25:94de:2ab
872c19:dd:d9:dd:c25:c25:94de:2ac/1272c19:dd:d9:dd:c25:c25:94de:2ad
882c19:dd:d9:dd:c25:c25:94de:2ae/1272c19:dd:d9:dd:c25:c25:94de:2af
892c19:dd:d9:dd:c25:c25:94de:2b0/1272c19:dd:d9:dd:c25:c25:94de:2b1
902c19:dd:d9:dd:c25:c25:94de:2b2/1272c19:dd:d9:dd:c25:c25:94de:2b3
912c19:dd:d9:dd:c25:c25:94de:2b4/1272c19:dd:d9:dd:c25:c25:94de:2b5
922c19:dd:d9:dd:c25:c25:94de:2b6/1272c19:dd:d9:dd:c25:c25:94de:2b7
932c19:dd:d9:dd:c25:c25:94de:2b8/1272c19:dd:d9:dd:c25:c25:94de:2b9
942c19:dd:d9:dd:c25:c25:94de:2ba/1272c19:dd:d9:dd:c25:c25:94de:2bb
952c19:dd:d9:dd:c25:c25:94de:2bc/1272c19:dd:d9:dd:c25:c25:94de:2bd
962c19:dd:d9:dd:c25:c25:94de:2be/1272c19:dd:d9:dd:c25:c25:94de:2bf
972c19:dd:d9:dd:c25:c25:94de:2c0/1272c19:dd:d9:dd:c25:c25:94de:2c1
982c19:dd:d9:dd:c25:c25:94de:2c2/1272c19:dd:d9:dd:c25:c25:94de:2c3
992c19:dd:d9:dd:c25:c25:94de:2c4/1272c19:dd:d9:dd:c25:c25:94de:2c5
1002c19:dd:d9:dd:c25:c25:94de:2c6/1272c19:dd:d9:dd:c25:c25:94de:2c7
1012c19:dd:d9:dd:c25:c25:94de:2c8/1272c19:dd:d9:dd:c25:c25:94de:2c9
1022c19:dd:d9:dd:c25:c25:94de:2ca/1272c19:dd:d9:dd:c25:c25:94de:2cb
1032c19:dd:d9:dd:c25:c25:94de:2cc/1272c19:dd:d9:dd:c25:c25:94de:2cd
1042c19:dd:d9:dd:c25:c25:94de:2ce/1272c19:dd:d9:dd:c25:c25:94de:2cf
1052c19:dd:d9:dd:c25:c25:94de:2d0/1272c19:dd:d9:dd:c25:c25:94de:2d1
1062c19:dd:d9:dd:c25:c25:94de:2d2/1272c19:dd:d9:dd:c25:c25:94de:2d3
1072c19:dd:d9:dd:c25:c25:94de:2d4/1272c19:dd:d9:dd:c25:c25:94de:2d5
1082c19:dd:d9:dd:c25:c25:94de:2d6/1272c19:dd:d9:dd:c25:c25:94de:2d7
1092c19:dd:d9:dd:c25:c25:94de:2d8/1272c19:dd:d9:dd:c25:c25:94de:2d9
1102c19:dd:d9:dd:c25:c25:94de:2da/1272c19:dd:d9:dd:c25:c25:94de:2db
1112c19:dd:d9:dd:c25:c25:94de:2dc/1272c19:dd:d9:dd:c25:c25:94de:2dd
1122c19:dd:d9:dd:c25:c25:94de:2de/1272c19:dd:d9:dd:c25:c25:94de:2df
1132c19:dd:d9:dd:c25:c25:94de:2e0/1272c19:dd:d9:dd:c25:c25:94de:2e1
1142c19:dd:d9:dd:c25:c25:94de:2e2/1272c19:dd:d9:dd:c25:c25:94de:2e3
1152c19:dd:d9:dd:c25:c25:94de:2e4/1272c19:dd:d9:dd:c25:c25:94de:2e5
1162c19:dd:d9:dd:c25:c25:94de:2e6/1272c19:dd:d9:dd:c25:c25:94de:2e7
1172c19:dd:d9:dd:c25:c25:94de:2e8/1272c19:dd:d9:dd:c25:c25:94de:2e9
1182c19:dd:d9:dd:c25:c25:94de:2ea/1272c19:dd:d9:dd:c25:c25:94de:2eb
1192c19:dd:d9:dd:c25:c25:94de:2ec/1272c19:dd:d9:dd:c25:c25:94de:2ed
1202c19:dd:d9:dd:c25:c25:94de:2ee/1272c19:dd:d9:dd:c25:c25:94de:2ef
1212c19:dd:d9:dd:c25:c25:94de:2f0/1272c19:dd:d9:dd:c25:c25:94de:2f1
1222c19:dd:d9:dd:c25:c25:94de:2f2/1272c19:dd:d9:dd:c25:c25:94de:2f3
1232c19:dd:d9:dd:c25:c25:94de:2f4/1272c19:dd:d9:dd:c25:c25:94de:2f5
1242c19:dd:d9:dd:c25:c25:94de:2f6/1272c19:dd:d9:dd:c25:c25:94de:2f7
1252c19:dd:d9:dd:c25:c25:94de:2f8/1272c19:dd:d9:dd:c25:c25:94de:2f9
1262c19:dd:d9:dd:c25:c25:94de:2fa/1272c19:dd:d9:dd:c25:c25:94de:2fb
1272c19:dd:d9:dd:c25:c25:94de:2fc/1272c19:dd:d9:dd:c25:c25:94de:2fd
1282c19:dd:d9:dd:c25:c25:94de:2fe/1272c19:dd:d9:dd:c25:c25:94de:2ff
1292c19:dd:d9:dd:c25:c25:94de:300/1272c19:dd:d9:dd:c25:c25:94de:301
1302c19:dd:d9:dd:c25:c25:94de:302/1272c19:dd:d9:dd:c25:c25:94de:303
1312c19:dd:d9:dd:c25:c25:94de:304/1272c19:dd:d9:dd:c25:c25:94de:305
1322c19:dd:d9:dd:c25:c25:94de:306/1272c19:dd:d9:dd:c25:c25:94de:307
1332c19:dd:d9:dd:c25:c25:94de:308/1272c19:dd:d9:dd:c25:c25:94de:309
1342c19:dd:d9:dd:c25:c25:94de:30a/1272c19:dd:d9:dd:c25:c25:94de:30b
1352c19:dd:d9:dd:c25:c25:94de:30c/1272c19:dd:d9:dd:c25:c25:94de:30d
1362c19:dd:d9:dd:c25:c25:94de:30e/1272c19:dd:d9:dd:c25:c25:94de:30f
1372c19:dd:d9:dd:c25:c25:94de:310/1272c19:dd:d9:dd:c25:c25:94de:311
1382c19:dd:d9:dd:c25:c25:94de:312/1272c19:dd:d9:dd:c25:c25:94de:313
1392c19:dd:d9:dd:c25:c25:94de:314/1272c19:dd:d9:dd:c25:c25:94de:315
1402c19:dd:d9:dd:c25:c25:94de:316/1272c19:dd:d9:dd:c25:c25:94de:317
1412c19:dd:d9:dd:c25:c25:94de:318/1272c19:dd:d9:dd:c25:c25:94de:319
1422c19:dd:d9:dd:c25:c25:94de:31a/1272c19:dd:d9:dd:c25:c25:94de:31b
1432c19:dd:d9:dd:c25:c25:94de:31c/1272c19:dd:d9:dd:c25:c25:94de:31d
1442c19:dd:d9:dd:c25:c25:94de:31e/1272c19:dd:d9:dd:c25:c25:94de:31f
1452c19:dd:d9:dd:c25:c25:94de:320/1272c19:dd:d9:dd:c25:c25:94de:321
1462c19:dd:d9:dd:c25:c25:94de:322/1272c19:dd:d9:dd:c25:c25:94de:323
1472c19:dd:d9:dd:c25:c25:94de:324/1272c19:dd:d9:dd:c25:c25:94de:325
1482c19:dd:d9:dd:c25:c25:94de:326/1272c19:dd:d9:dd:c25:c25:94de:327
1492c19:dd:d9:dd:c25:c25:94de:328/1272c19:dd:d9:dd:c25:c25:94de:329
1502c19:dd:d9:dd:c25:c25:94de:32a/1272c19:dd:d9:dd:c25:c25:94de:32b
1512c19:dd:d9:dd:c25:c25:94de:32c/1272c19:dd:d9:dd:c25:c25:94de:32d
1522c19:dd:d9:dd:c25:c25:94de:32e/1272c19:dd:d9:dd:c25:c25:94de:32f
1532c19:dd:d9:dd:c25:c25:94de:330/1272c19:dd:d9:dd:c25:c25:94de:331
1542c19:dd:d9:dd:c25:c25:94de:332/1272c19:dd:d9:dd:c25:c25:94de:333
1552c19:dd:d9:dd:c25:c25:94de:334/1272c19:dd:d9:dd:c25:c25:94de:335
1562c19:dd:d9:dd:c25:c25:94de:336/1272c19:dd:d9:dd:c25:c25:94de:337
1572c19:dd:d9:dd:c25:c25:94de:338/1272c19:dd:d9:dd:c25:c25:94de:339
1582c19:dd:d9:dd:c25:c25:94de:33a/1272c19:dd:d9:dd:c25:c25:94de:33b
1592c19:dd:d9:dd:c25:c25:94de:33c/1272c19:dd:d9:dd:c25:c25:94de:33d
1602c19:dd:d9:dd:c25:c25:94de:33e/1272c19:dd:d9:dd:c25:c25:94de:33f
1612c19:dd:d9:dd:c25:c25:94de:340/1272c19:dd:d9:dd:c25:c25:94de:341
1622c19:dd:d9:dd:c25:c25:94de:342/1272c19:dd:d9:dd:c25:c25:94de:343
1632c19:dd:d9:dd:c25:c25:94de:344/1272c19:dd:d9:dd:c25:c25:94de:345
1642c19:dd:d9:dd:c25:c25:94de:346/1272c19:dd:d9:dd:c25:c25:94de:347
1652c19:dd:d9:dd:c25:c25:94de:348/1272c19:dd:d9:dd:c25:c25:94de:349
1662c19:dd:d9:dd:c25:c25:94de:34a/1272c19:dd:d9:dd:c25:c25:94de:34b
1672c19:dd:d9:dd:c25:c25:94de:34c/1272c19:dd:d9:dd:c25:c25:94de:34d
1682c19:dd:d9:dd:c25:c25:94de:34e/1272c19:dd:d9:dd:c25:c25:94de:34f
1692c19:dd:d9:dd:c25:c25:94de:350/1272c19:dd:d9:dd:c25:c25:94de:351
1702c19:dd:d9:dd:c25:c25:94de:352/1272c19:dd:d9:dd:c25:c25:94de:353
1712c19:dd:d9:dd:c25:c25:94de:354/1272c19:dd:d9:dd:c25:c25:94de:355
1722c19:dd:d9:dd:c25:c25:94de:356/1272c19:dd:d9:dd:c25:c25:94de:357
1732c19:dd:d9:dd:c25:c25:94de:358/1272c19:dd:d9:dd:c25:c25:94de:359
1742c19:dd:d9:dd:c25:c25:94de:35a/1272c19:dd:d9:dd:c25:c25:94de:35b
1752c19:dd:d9:dd:c25:c25:94de:35c/1272c19:dd:d9:dd:c25:c25:94de:35d
1762c19:dd:d9:dd:c25:c25:94de:35e/1272c19:dd:d9:dd:c25:c25:94de:35f
1772c19:dd:d9:dd:c25:c25:94de:360/1272c19:dd:d9:dd:c25:c25:94de:361
1782c19:dd:d9:dd:c25:c25:94de:362/1272c19:dd:d9:dd:c25:c25:94de:363
1792c19:dd:d9:dd:c25:c25:94de:364/1272c19:dd:d9:dd:c25:c25:94de:365
1802c19:dd:d9:dd:c25:c25:94de:366/1272c19:dd:d9:dd:c25:c25:94de:367
1812c19:dd:d9:dd:c25:c25:94de:368/1272c19:dd:d9:dd:c25:c25:94de:369
1822c19:dd:d9:dd:c25:c25:94de:36a/1272c19:dd:d9:dd:c25:c25:94de:36b
1832c19:dd:d9:dd:c25:c25:94de:36c/1272c19:dd:d9:dd:c25:c25:94de:36d
1842c19:dd:d9:dd:c25:c25:94de:36e/1272c19:dd:d9:dd:c25:c25:94de:36f
1852c19:dd:d9:dd:c25:c25:94de:370/1272c19:dd:d9:dd:c25:c25:94de:371
1862c19:dd:d9:dd:c25:c25:94de:372/1272c19:dd:d9:dd:c25:c25:94de:373
1872c19:dd:d9:dd:c25:c25:94de:374/1272c19:dd:d9:dd:c25:c25:94de:375
1882c19:dd:d9:dd:c25:c25:94de:376/1272c19:dd:d9:dd:c25:c25:94de:377
1892c19:dd:d9:dd:c25:c25:94de:378/1272c19:dd:d9:dd:c25:c25:94de:379
1902c19:dd:d9:dd:c25:c25:94de:37a/1272c19:dd:d9:dd:c25:c25:94de:37b
1912c19:dd:d9:dd:c25:c25:94de:37c/1272c19:dd:d9:dd:c25:c25:94de:37d
1922c19:dd:d9:dd:c25:c25:94de:37e/1272c19:dd:d9:dd:c25:c25:94de:37f
1932c19:dd:d9:dd:c25:c25:94de:380/1272c19:dd:d9:dd:c25:c25:94de:381
1942c19:dd:d9:dd:c25:c25:94de:382/1272c19:dd:d9:dd:c25:c25:94de:383
1952c19:dd:d9:dd:c25:c25:94de:384/1272c19:dd:d9:dd:c25:c25:94de:385
1962c19:dd:d9:dd:c25:c25:94de:386/1272c19:dd:d9:dd:c25:c25:94de:387
1972c19:dd:d9:dd:c25:c25:94de:388/1272c19:dd:d9:dd:c25:c25:94de:389
1982c19:dd:d9:dd:c25:c25:94de:38a/1272c19:dd:d9:dd:c25:c25:94de:38b
1992c19:dd:d9:dd:c25:c25:94de:38c/1272c19:dd:d9:dd:c25:c25:94de:38d
2002c19:dd:d9:dd:c25:c25:94de:38e/1272c19:dd:d9:dd:c25:c25:94de:38f
2012c19:dd:d9:dd:c25:c25:94de:390/1272c19:dd:d9:dd:c25:c25:94de:391
2022c19:dd:d9:dd:c25:c25:94de:392/1272c19:dd:d9:dd:c25:c25:94de:393
2032c19:dd:d9:dd:c25:c25:94de:394/1272c19:dd:d9:dd:c25:c25:94de:395
2042c19:dd:d9:dd:c25:c25:94de:396/1272c19:dd:d9:dd:c25:c25:94de:397
2052c19:dd:d9:dd:c25:c25:94de:398/1272c19:dd:d9:dd:c25:c25:94de:399
2062c19:dd:d9:dd:c25:c25:94de:39a/1272c19:dd:d9:dd:c25:c25:94de:39b
2072c19:dd:d9:dd:c25:c25:94de:39c/1272c19:dd:d9:dd:c25:c25:94de:39d
2082c19:dd:d9:dd:c25:c25:94de:39e/1272c19:dd:d9:dd:c25:c25:94de:39f
2092c19:dd:d9:dd:c25:c25:94de:3a0/1272c19:dd:d9:dd:c25:c25:94de:3a1
2102c19:dd:d9:dd:c25:c25:94de:3a2/1272c19:dd:d9:dd:c25:c25:94de:3a3
2112c19:dd:d9:dd:c25:c25:94de:3a4/1272c19:dd:d9:dd:c25:c25:94de:3a5
2122c19:dd:d9:dd:c25:c25:94de:3a6/1272c19:dd:d9:dd:c25:c25:94de:3a7
2132c19:dd:d9:dd:c25:c25:94de:3a8/1272c19:dd:d9:dd:c25:c25:94de:3a9
2142c19:dd:d9:dd:c25:c25:94de:3aa/1272c19:dd:d9:dd:c25:c25:94de:3ab
2152c19:dd:d9:dd:c25:c25:94de:3ac/1272c19:dd:d9:dd:c25:c25:94de:3ad
2162c19:dd:d9:dd:c25:c25:94de:3ae/1272c19:dd:d9:dd:c25:c25:94de:3af
2172c19:dd:d9:dd:c25:c25:94de:3b0/1272c19:dd:d9:dd:c25:c25:94de:3b1
2182c19:dd:d9:dd:c25:c25:94de:3b2/1272c19:dd:d9:dd:c25:c25:94de:3b3
2192c19:dd:d9:dd:c25:c25:94de:3b4/1272c19:dd:d9:dd:c25:c25:94de:3b5
2202c19:dd:d9:dd:c25:c25:94de:3b6/1272c19:dd:d9:dd:c25:c25:94de:3b7
2212c19:dd:d9:dd:c25:c25:94de:3b8/1272c19:dd:d9:dd:c25:c25:94de:3b9
2222c19:dd:d9:dd:c25:c25:94de:3ba/1272c19:dd:d9:dd:c25:c25:94de:3bb
2232c19:dd:d9:dd:c25:c25:94de:3bc/1272c19:dd:d9:dd:c25:c25:94de:3bd
2242c19:dd:d9:dd:c25:c25:94de:3be/1272c19:dd:d9:dd:c25:c25:94de:3bf
2252c19:dd:d9:dd:c25:c25:94de:3c0/1272c19:dd:d9:dd:c25:c25:94de:3c1
2262c19:dd:d9:dd:c25:c25:94de:3c2/1272c19:dd:d9:dd:c25:c25:94de:3c3
2272c19:dd:d9:dd:c25:c25:94de:3c4/1272c19:dd:d9:dd:c25:c25:94de:3c5
2282c19:dd:d9:dd:c25:c25:94de:3c6/1272c19:dd:d9:dd:c25:c25:94de:3c7
2292c19:dd:d9:dd:c25:c25:94de:3c8/1272c19:dd:d9:dd:c25:c25:94de:3c9
2302c19:dd:d9:dd:c25:c25:94de:3ca/1272c19:dd:d9:dd:c25:c25:94de:3cb
2312c19:dd:d9:dd:c25:c25:94de:3cc/1272c19:dd:d9:dd:c25:c25:94de:3cd
2322c19:dd:d9:dd:c25:c25:94de:3ce/1272c19:dd:d9:dd:c25:c25:94de:3cf
2332c19:dd:d9:dd:c25:c25:94de:3d0/1272c19:dd:d9:dd:c25:c25:94de:3d1
2342c19:dd:d9:dd:c25:c25:94de:3d2/1272c19:dd:d9:dd:c25:c25:94de:3d3
2352c19:dd:d9:dd:c25:c25:94de:3d4/1272c19:dd:d9:dd:c25:c25:94de:3d5
2362c19:dd:d9:dd:c25:c25:94de:3d6/1272c19:dd:d9:dd:c25:c25:94de:3d7
2372c19:dd:d9:dd:c25:c25:94de:3d8/1272c19:dd:d9:dd:c25:c25:94de:3d9
2382c19:dd:d9:dd:c25:c25:94de:3da/1272c19:dd:d9:dd:c25:c25:94de:3db
2392c19:dd:d9:dd:c25:c25:94de:3dc/1272c19:dd:d9:dd:c25:c25:94de:3dd
2402c19:dd:d9:dd:c25:c25:94de:3de/1272c19:dd:d9:dd:c25:c25:94de:3df
2412c19:dd:d9:dd:c25:c25:94de:3e0/1272c19:dd:d9:dd:c25:c25:94de:3e1
2422c19:dd:d9:dd:c25:c25:94de:3e2/1272c19:dd:d9:dd:c25:c25:94de:3e3
2432c19:dd:d9:dd:c25:c25:94de:3e4/1272c19:dd:d9:dd:c25:c25:94de:3e5
2442c19:dd:d9:dd:c25:c25:94de:3e6/1272c19:dd:d9:dd:c25:c25:94de:3e7
2452c19:dd:d9:dd:c25:c25:94de:3e8/1272c19:dd:d9:dd:c25:c25:94de:3e9
2462c19:dd:d9:dd:c25:c25:94de:3ea/1272c19:dd:d9:dd:c25:c25:94de:3eb
2472c19:dd:d9:dd:c25:c25:94de:3ec/1272c19:dd:d9:dd:c25:c25:94de:3ed
2482c19:dd:d9:dd:c25:c25:94de:3ee/1272c19:dd:d9:dd:c25:c25:94de:3ef
2492c19:dd:d9:dd:c25:c25:94de:3f0/1272c19:dd:d9:dd:c25:c25:94de:3f1
2502c19:dd:d9:dd:c25:c25:94de:3f2/1272c19:dd:d9:dd:c25:c25:94de:3f3
2512c19:dd:d9:dd:c25:c25:94de:3f4/1272c19:dd:d9:dd:c25:c25:94de:3f5
2522c19:dd:d9:dd:c25:c25:94de:3f6/1272c19:dd:d9:dd:c25:c25:94de:3f7
2532c19:dd:d9:dd:c25:c25:94de:3f8/1272c19:dd:d9:dd:c25:c25:94de:3f9
2542c19:dd:d9:dd:c25:c25:94de:3fa/1272c19:dd:d9:dd:c25:c25:94de:3fb
2552c19:dd:d9:dd:c25:c25:94de:3fc/1272c19:dd:d9:dd:c25:c25:94de:3fd
2562c19:dd:d9:dd:c25:c25:94de:3fe/1272c19:dd:d9:dd:c25:c25:94de:3ff

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.