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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:7200/119
First address
2c19:dd:d9:dd:c25:c25:94de:7200
Last address
2c19:dd:d9:dd:c25:c25:94de:73ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:7200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.7.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
3.7.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:7200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:7200/1272c19:dd:d9:dd:c25:c25:94de:7201
22c19:dd:d9:dd:c25:c25:94de:7202/1272c19:dd:d9:dd:c25:c25:94de:7203
32c19:dd:d9:dd:c25:c25:94de:7204/1272c19:dd:d9:dd:c25:c25:94de:7205
42c19:dd:d9:dd:c25:c25:94de:7206/1272c19:dd:d9:dd:c25:c25:94de:7207
52c19:dd:d9:dd:c25:c25:94de:7208/1272c19:dd:d9:dd:c25:c25:94de:7209
62c19:dd:d9:dd:c25:c25:94de:720a/1272c19:dd:d9:dd:c25:c25:94de:720b
72c19:dd:d9:dd:c25:c25:94de:720c/1272c19:dd:d9:dd:c25:c25:94de:720d
82c19:dd:d9:dd:c25:c25:94de:720e/1272c19:dd:d9:dd:c25:c25:94de:720f
92c19:dd:d9:dd:c25:c25:94de:7210/1272c19:dd:d9:dd:c25:c25:94de:7211
102c19:dd:d9:dd:c25:c25:94de:7212/1272c19:dd:d9:dd:c25:c25:94de:7213
112c19:dd:d9:dd:c25:c25:94de:7214/1272c19:dd:d9:dd:c25:c25:94de:7215
122c19:dd:d9:dd:c25:c25:94de:7216/1272c19:dd:d9:dd:c25:c25:94de:7217
132c19:dd:d9:dd:c25:c25:94de:7218/1272c19:dd:d9:dd:c25:c25:94de:7219
142c19:dd:d9:dd:c25:c25:94de:721a/1272c19:dd:d9:dd:c25:c25:94de:721b
152c19:dd:d9:dd:c25:c25:94de:721c/1272c19:dd:d9:dd:c25:c25:94de:721d
162c19:dd:d9:dd:c25:c25:94de:721e/1272c19:dd:d9:dd:c25:c25:94de:721f
172c19:dd:d9:dd:c25:c25:94de:7220/1272c19:dd:d9:dd:c25:c25:94de:7221
182c19:dd:d9:dd:c25:c25:94de:7222/1272c19:dd:d9:dd:c25:c25:94de:7223
192c19:dd:d9:dd:c25:c25:94de:7224/1272c19:dd:d9:dd:c25:c25:94de:7225
202c19:dd:d9:dd:c25:c25:94de:7226/1272c19:dd:d9:dd:c25:c25:94de:7227
212c19:dd:d9:dd:c25:c25:94de:7228/1272c19:dd:d9:dd:c25:c25:94de:7229
222c19:dd:d9:dd:c25:c25:94de:722a/1272c19:dd:d9:dd:c25:c25:94de:722b
232c19:dd:d9:dd:c25:c25:94de:722c/1272c19:dd:d9:dd:c25:c25:94de:722d
242c19:dd:d9:dd:c25:c25:94de:722e/1272c19:dd:d9:dd:c25:c25:94de:722f
252c19:dd:d9:dd:c25:c25:94de:7230/1272c19:dd:d9:dd:c25:c25:94de:7231
262c19:dd:d9:dd:c25:c25:94de:7232/1272c19:dd:d9:dd:c25:c25:94de:7233
272c19:dd:d9:dd:c25:c25:94de:7234/1272c19:dd:d9:dd:c25:c25:94de:7235
282c19:dd:d9:dd:c25:c25:94de:7236/1272c19:dd:d9:dd:c25:c25:94de:7237
292c19:dd:d9:dd:c25:c25:94de:7238/1272c19:dd:d9:dd:c25:c25:94de:7239
302c19:dd:d9:dd:c25:c25:94de:723a/1272c19:dd:d9:dd:c25:c25:94de:723b
312c19:dd:d9:dd:c25:c25:94de:723c/1272c19:dd:d9:dd:c25:c25:94de:723d
322c19:dd:d9:dd:c25:c25:94de:723e/1272c19:dd:d9:dd:c25:c25:94de:723f
332c19:dd:d9:dd:c25:c25:94de:7240/1272c19:dd:d9:dd:c25:c25:94de:7241
342c19:dd:d9:dd:c25:c25:94de:7242/1272c19:dd:d9:dd:c25:c25:94de:7243
352c19:dd:d9:dd:c25:c25:94de:7244/1272c19:dd:d9:dd:c25:c25:94de:7245
362c19:dd:d9:dd:c25:c25:94de:7246/1272c19:dd:d9:dd:c25:c25:94de:7247
372c19:dd:d9:dd:c25:c25:94de:7248/1272c19:dd:d9:dd:c25:c25:94de:7249
382c19:dd:d9:dd:c25:c25:94de:724a/1272c19:dd:d9:dd:c25:c25:94de:724b
392c19:dd:d9:dd:c25:c25:94de:724c/1272c19:dd:d9:dd:c25:c25:94de:724d
402c19:dd:d9:dd:c25:c25:94de:724e/1272c19:dd:d9:dd:c25:c25:94de:724f
412c19:dd:d9:dd:c25:c25:94de:7250/1272c19:dd:d9:dd:c25:c25:94de:7251
422c19:dd:d9:dd:c25:c25:94de:7252/1272c19:dd:d9:dd:c25:c25:94de:7253
432c19:dd:d9:dd:c25:c25:94de:7254/1272c19:dd:d9:dd:c25:c25:94de:7255
442c19:dd:d9:dd:c25:c25:94de:7256/1272c19:dd:d9:dd:c25:c25:94de:7257
452c19:dd:d9:dd:c25:c25:94de:7258/1272c19:dd:d9:dd:c25:c25:94de:7259
462c19:dd:d9:dd:c25:c25:94de:725a/1272c19:dd:d9:dd:c25:c25:94de:725b
472c19:dd:d9:dd:c25:c25:94de:725c/1272c19:dd:d9:dd:c25:c25:94de:725d
482c19:dd:d9:dd:c25:c25:94de:725e/1272c19:dd:d9:dd:c25:c25:94de:725f
492c19:dd:d9:dd:c25:c25:94de:7260/1272c19:dd:d9:dd:c25:c25:94de:7261
502c19:dd:d9:dd:c25:c25:94de:7262/1272c19:dd:d9:dd:c25:c25:94de:7263
512c19:dd:d9:dd:c25:c25:94de:7264/1272c19:dd:d9:dd:c25:c25:94de:7265
522c19:dd:d9:dd:c25:c25:94de:7266/1272c19:dd:d9:dd:c25:c25:94de:7267
532c19:dd:d9:dd:c25:c25:94de:7268/1272c19:dd:d9:dd:c25:c25:94de:7269
542c19:dd:d9:dd:c25:c25:94de:726a/1272c19:dd:d9:dd:c25:c25:94de:726b
552c19:dd:d9:dd:c25:c25:94de:726c/1272c19:dd:d9:dd:c25:c25:94de:726d
562c19:dd:d9:dd:c25:c25:94de:726e/1272c19:dd:d9:dd:c25:c25:94de:726f
572c19:dd:d9:dd:c25:c25:94de:7270/1272c19:dd:d9:dd:c25:c25:94de:7271
582c19:dd:d9:dd:c25:c25:94de:7272/1272c19:dd:d9:dd:c25:c25:94de:7273
592c19:dd:d9:dd:c25:c25:94de:7274/1272c19:dd:d9:dd:c25:c25:94de:7275
602c19:dd:d9:dd:c25:c25:94de:7276/1272c19:dd:d9:dd:c25:c25:94de:7277
612c19:dd:d9:dd:c25:c25:94de:7278/1272c19:dd:d9:dd:c25:c25:94de:7279
622c19:dd:d9:dd:c25:c25:94de:727a/1272c19:dd:d9:dd:c25:c25:94de:727b
632c19:dd:d9:dd:c25:c25:94de:727c/1272c19:dd:d9:dd:c25:c25:94de:727d
642c19:dd:d9:dd:c25:c25:94de:727e/1272c19:dd:d9:dd:c25:c25:94de:727f
652c19:dd:d9:dd:c25:c25:94de:7280/1272c19:dd:d9:dd:c25:c25:94de:7281
662c19:dd:d9:dd:c25:c25:94de:7282/1272c19:dd:d9:dd:c25:c25:94de:7283
672c19:dd:d9:dd:c25:c25:94de:7284/1272c19:dd:d9:dd:c25:c25:94de:7285
682c19:dd:d9:dd:c25:c25:94de:7286/1272c19:dd:d9:dd:c25:c25:94de:7287
692c19:dd:d9:dd:c25:c25:94de:7288/1272c19:dd:d9:dd:c25:c25:94de:7289
702c19:dd:d9:dd:c25:c25:94de:728a/1272c19:dd:d9:dd:c25:c25:94de:728b
712c19:dd:d9:dd:c25:c25:94de:728c/1272c19:dd:d9:dd:c25:c25:94de:728d
722c19:dd:d9:dd:c25:c25:94de:728e/1272c19:dd:d9:dd:c25:c25:94de:728f
732c19:dd:d9:dd:c25:c25:94de:7290/1272c19:dd:d9:dd:c25:c25:94de:7291
742c19:dd:d9:dd:c25:c25:94de:7292/1272c19:dd:d9:dd:c25:c25:94de:7293
752c19:dd:d9:dd:c25:c25:94de:7294/1272c19:dd:d9:dd:c25:c25:94de:7295
762c19:dd:d9:dd:c25:c25:94de:7296/1272c19:dd:d9:dd:c25:c25:94de:7297
772c19:dd:d9:dd:c25:c25:94de:7298/1272c19:dd:d9:dd:c25:c25:94de:7299
782c19:dd:d9:dd:c25:c25:94de:729a/1272c19:dd:d9:dd:c25:c25:94de:729b
792c19:dd:d9:dd:c25:c25:94de:729c/1272c19:dd:d9:dd:c25:c25:94de:729d
802c19:dd:d9:dd:c25:c25:94de:729e/1272c19:dd:d9:dd:c25:c25:94de:729f
812c19:dd:d9:dd:c25:c25:94de:72a0/1272c19:dd:d9:dd:c25:c25:94de:72a1
822c19:dd:d9:dd:c25:c25:94de:72a2/1272c19:dd:d9:dd:c25:c25:94de:72a3
832c19:dd:d9:dd:c25:c25:94de:72a4/1272c19:dd:d9:dd:c25:c25:94de:72a5
842c19:dd:d9:dd:c25:c25:94de:72a6/1272c19:dd:d9:dd:c25:c25:94de:72a7
852c19:dd:d9:dd:c25:c25:94de:72a8/1272c19:dd:d9:dd:c25:c25:94de:72a9
862c19:dd:d9:dd:c25:c25:94de:72aa/1272c19:dd:d9:dd:c25:c25:94de:72ab
872c19:dd:d9:dd:c25:c25:94de:72ac/1272c19:dd:d9:dd:c25:c25:94de:72ad
882c19:dd:d9:dd:c25:c25:94de:72ae/1272c19:dd:d9:dd:c25:c25:94de:72af
892c19:dd:d9:dd:c25:c25:94de:72b0/1272c19:dd:d9:dd:c25:c25:94de:72b1
902c19:dd:d9:dd:c25:c25:94de:72b2/1272c19:dd:d9:dd:c25:c25:94de:72b3
912c19:dd:d9:dd:c25:c25:94de:72b4/1272c19:dd:d9:dd:c25:c25:94de:72b5
922c19:dd:d9:dd:c25:c25:94de:72b6/1272c19:dd:d9:dd:c25:c25:94de:72b7
932c19:dd:d9:dd:c25:c25:94de:72b8/1272c19:dd:d9:dd:c25:c25:94de:72b9
942c19:dd:d9:dd:c25:c25:94de:72ba/1272c19:dd:d9:dd:c25:c25:94de:72bb
952c19:dd:d9:dd:c25:c25:94de:72bc/1272c19:dd:d9:dd:c25:c25:94de:72bd
962c19:dd:d9:dd:c25:c25:94de:72be/1272c19:dd:d9:dd:c25:c25:94de:72bf
972c19:dd:d9:dd:c25:c25:94de:72c0/1272c19:dd:d9:dd:c25:c25:94de:72c1
982c19:dd:d9:dd:c25:c25:94de:72c2/1272c19:dd:d9:dd:c25:c25:94de:72c3
992c19:dd:d9:dd:c25:c25:94de:72c4/1272c19:dd:d9:dd:c25:c25:94de:72c5
1002c19:dd:d9:dd:c25:c25:94de:72c6/1272c19:dd:d9:dd:c25:c25:94de:72c7
1012c19:dd:d9:dd:c25:c25:94de:72c8/1272c19:dd:d9:dd:c25:c25:94de:72c9
1022c19:dd:d9:dd:c25:c25:94de:72ca/1272c19:dd:d9:dd:c25:c25:94de:72cb
1032c19:dd:d9:dd:c25:c25:94de:72cc/1272c19:dd:d9:dd:c25:c25:94de:72cd
1042c19:dd:d9:dd:c25:c25:94de:72ce/1272c19:dd:d9:dd:c25:c25:94de:72cf
1052c19:dd:d9:dd:c25:c25:94de:72d0/1272c19:dd:d9:dd:c25:c25:94de:72d1
1062c19:dd:d9:dd:c25:c25:94de:72d2/1272c19:dd:d9:dd:c25:c25:94de:72d3
1072c19:dd:d9:dd:c25:c25:94de:72d4/1272c19:dd:d9:dd:c25:c25:94de:72d5
1082c19:dd:d9:dd:c25:c25:94de:72d6/1272c19:dd:d9:dd:c25:c25:94de:72d7
1092c19:dd:d9:dd:c25:c25:94de:72d8/1272c19:dd:d9:dd:c25:c25:94de:72d9
1102c19:dd:d9:dd:c25:c25:94de:72da/1272c19:dd:d9:dd:c25:c25:94de:72db
1112c19:dd:d9:dd:c25:c25:94de:72dc/1272c19:dd:d9:dd:c25:c25:94de:72dd
1122c19:dd:d9:dd:c25:c25:94de:72de/1272c19:dd:d9:dd:c25:c25:94de:72df
1132c19:dd:d9:dd:c25:c25:94de:72e0/1272c19:dd:d9:dd:c25:c25:94de:72e1
1142c19:dd:d9:dd:c25:c25:94de:72e2/1272c19:dd:d9:dd:c25:c25:94de:72e3
1152c19:dd:d9:dd:c25:c25:94de:72e4/1272c19:dd:d9:dd:c25:c25:94de:72e5
1162c19:dd:d9:dd:c25:c25:94de:72e6/1272c19:dd:d9:dd:c25:c25:94de:72e7
1172c19:dd:d9:dd:c25:c25:94de:72e8/1272c19:dd:d9:dd:c25:c25:94de:72e9
1182c19:dd:d9:dd:c25:c25:94de:72ea/1272c19:dd:d9:dd:c25:c25:94de:72eb
1192c19:dd:d9:dd:c25:c25:94de:72ec/1272c19:dd:d9:dd:c25:c25:94de:72ed
1202c19:dd:d9:dd:c25:c25:94de:72ee/1272c19:dd:d9:dd:c25:c25:94de:72ef
1212c19:dd:d9:dd:c25:c25:94de:72f0/1272c19:dd:d9:dd:c25:c25:94de:72f1
1222c19:dd:d9:dd:c25:c25:94de:72f2/1272c19:dd:d9:dd:c25:c25:94de:72f3
1232c19:dd:d9:dd:c25:c25:94de:72f4/1272c19:dd:d9:dd:c25:c25:94de:72f5
1242c19:dd:d9:dd:c25:c25:94de:72f6/1272c19:dd:d9:dd:c25:c25:94de:72f7
1252c19:dd:d9:dd:c25:c25:94de:72f8/1272c19:dd:d9:dd:c25:c25:94de:72f9
1262c19:dd:d9:dd:c25:c25:94de:72fa/1272c19:dd:d9:dd:c25:c25:94de:72fb
1272c19:dd:d9:dd:c25:c25:94de:72fc/1272c19:dd:d9:dd:c25:c25:94de:72fd
1282c19:dd:d9:dd:c25:c25:94de:72fe/1272c19:dd:d9:dd:c25:c25:94de:72ff
1292c19:dd:d9:dd:c25:c25:94de:7300/1272c19:dd:d9:dd:c25:c25:94de:7301
1302c19:dd:d9:dd:c25:c25:94de:7302/1272c19:dd:d9:dd:c25:c25:94de:7303
1312c19:dd:d9:dd:c25:c25:94de:7304/1272c19:dd:d9:dd:c25:c25:94de:7305
1322c19:dd:d9:dd:c25:c25:94de:7306/1272c19:dd:d9:dd:c25:c25:94de:7307
1332c19:dd:d9:dd:c25:c25:94de:7308/1272c19:dd:d9:dd:c25:c25:94de:7309
1342c19:dd:d9:dd:c25:c25:94de:730a/1272c19:dd:d9:dd:c25:c25:94de:730b
1352c19:dd:d9:dd:c25:c25:94de:730c/1272c19:dd:d9:dd:c25:c25:94de:730d
1362c19:dd:d9:dd:c25:c25:94de:730e/1272c19:dd:d9:dd:c25:c25:94de:730f
1372c19:dd:d9:dd:c25:c25:94de:7310/1272c19:dd:d9:dd:c25:c25:94de:7311
1382c19:dd:d9:dd:c25:c25:94de:7312/1272c19:dd:d9:dd:c25:c25:94de:7313
1392c19:dd:d9:dd:c25:c25:94de:7314/1272c19:dd:d9:dd:c25:c25:94de:7315
1402c19:dd:d9:dd:c25:c25:94de:7316/1272c19:dd:d9:dd:c25:c25:94de:7317
1412c19:dd:d9:dd:c25:c25:94de:7318/1272c19:dd:d9:dd:c25:c25:94de:7319
1422c19:dd:d9:dd:c25:c25:94de:731a/1272c19:dd:d9:dd:c25:c25:94de:731b
1432c19:dd:d9:dd:c25:c25:94de:731c/1272c19:dd:d9:dd:c25:c25:94de:731d
1442c19:dd:d9:dd:c25:c25:94de:731e/1272c19:dd:d9:dd:c25:c25:94de:731f
1452c19:dd:d9:dd:c25:c25:94de:7320/1272c19:dd:d9:dd:c25:c25:94de:7321
1462c19:dd:d9:dd:c25:c25:94de:7322/1272c19:dd:d9:dd:c25:c25:94de:7323
1472c19:dd:d9:dd:c25:c25:94de:7324/1272c19:dd:d9:dd:c25:c25:94de:7325
1482c19:dd:d9:dd:c25:c25:94de:7326/1272c19:dd:d9:dd:c25:c25:94de:7327
1492c19:dd:d9:dd:c25:c25:94de:7328/1272c19:dd:d9:dd:c25:c25:94de:7329
1502c19:dd:d9:dd:c25:c25:94de:732a/1272c19:dd:d9:dd:c25:c25:94de:732b
1512c19:dd:d9:dd:c25:c25:94de:732c/1272c19:dd:d9:dd:c25:c25:94de:732d
1522c19:dd:d9:dd:c25:c25:94de:732e/1272c19:dd:d9:dd:c25:c25:94de:732f
1532c19:dd:d9:dd:c25:c25:94de:7330/1272c19:dd:d9:dd:c25:c25:94de:7331
1542c19:dd:d9:dd:c25:c25:94de:7332/1272c19:dd:d9:dd:c25:c25:94de:7333
1552c19:dd:d9:dd:c25:c25:94de:7334/1272c19:dd:d9:dd:c25:c25:94de:7335
1562c19:dd:d9:dd:c25:c25:94de:7336/1272c19:dd:d9:dd:c25:c25:94de:7337
1572c19:dd:d9:dd:c25:c25:94de:7338/1272c19:dd:d9:dd:c25:c25:94de:7339
1582c19:dd:d9:dd:c25:c25:94de:733a/1272c19:dd:d9:dd:c25:c25:94de:733b
1592c19:dd:d9:dd:c25:c25:94de:733c/1272c19:dd:d9:dd:c25:c25:94de:733d
1602c19:dd:d9:dd:c25:c25:94de:733e/1272c19:dd:d9:dd:c25:c25:94de:733f
1612c19:dd:d9:dd:c25:c25:94de:7340/1272c19:dd:d9:dd:c25:c25:94de:7341
1622c19:dd:d9:dd:c25:c25:94de:7342/1272c19:dd:d9:dd:c25:c25:94de:7343
1632c19:dd:d9:dd:c25:c25:94de:7344/1272c19:dd:d9:dd:c25:c25:94de:7345
1642c19:dd:d9:dd:c25:c25:94de:7346/1272c19:dd:d9:dd:c25:c25:94de:7347
1652c19:dd:d9:dd:c25:c25:94de:7348/1272c19:dd:d9:dd:c25:c25:94de:7349
1662c19:dd:d9:dd:c25:c25:94de:734a/1272c19:dd:d9:dd:c25:c25:94de:734b
1672c19:dd:d9:dd:c25:c25:94de:734c/1272c19:dd:d9:dd:c25:c25:94de:734d
1682c19:dd:d9:dd:c25:c25:94de:734e/1272c19:dd:d9:dd:c25:c25:94de:734f
1692c19:dd:d9:dd:c25:c25:94de:7350/1272c19:dd:d9:dd:c25:c25:94de:7351
1702c19:dd:d9:dd:c25:c25:94de:7352/1272c19:dd:d9:dd:c25:c25:94de:7353
1712c19:dd:d9:dd:c25:c25:94de:7354/1272c19:dd:d9:dd:c25:c25:94de:7355
1722c19:dd:d9:dd:c25:c25:94de:7356/1272c19:dd:d9:dd:c25:c25:94de:7357
1732c19:dd:d9:dd:c25:c25:94de:7358/1272c19:dd:d9:dd:c25:c25:94de:7359
1742c19:dd:d9:dd:c25:c25:94de:735a/1272c19:dd:d9:dd:c25:c25:94de:735b
1752c19:dd:d9:dd:c25:c25:94de:735c/1272c19:dd:d9:dd:c25:c25:94de:735d
1762c19:dd:d9:dd:c25:c25:94de:735e/1272c19:dd:d9:dd:c25:c25:94de:735f
1772c19:dd:d9:dd:c25:c25:94de:7360/1272c19:dd:d9:dd:c25:c25:94de:7361
1782c19:dd:d9:dd:c25:c25:94de:7362/1272c19:dd:d9:dd:c25:c25:94de:7363
1792c19:dd:d9:dd:c25:c25:94de:7364/1272c19:dd:d9:dd:c25:c25:94de:7365
1802c19:dd:d9:dd:c25:c25:94de:7366/1272c19:dd:d9:dd:c25:c25:94de:7367
1812c19:dd:d9:dd:c25:c25:94de:7368/1272c19:dd:d9:dd:c25:c25:94de:7369
1822c19:dd:d9:dd:c25:c25:94de:736a/1272c19:dd:d9:dd:c25:c25:94de:736b
1832c19:dd:d9:dd:c25:c25:94de:736c/1272c19:dd:d9:dd:c25:c25:94de:736d
1842c19:dd:d9:dd:c25:c25:94de:736e/1272c19:dd:d9:dd:c25:c25:94de:736f
1852c19:dd:d9:dd:c25:c25:94de:7370/1272c19:dd:d9:dd:c25:c25:94de:7371
1862c19:dd:d9:dd:c25:c25:94de:7372/1272c19:dd:d9:dd:c25:c25:94de:7373
1872c19:dd:d9:dd:c25:c25:94de:7374/1272c19:dd:d9:dd:c25:c25:94de:7375
1882c19:dd:d9:dd:c25:c25:94de:7376/1272c19:dd:d9:dd:c25:c25:94de:7377
1892c19:dd:d9:dd:c25:c25:94de:7378/1272c19:dd:d9:dd:c25:c25:94de:7379
1902c19:dd:d9:dd:c25:c25:94de:737a/1272c19:dd:d9:dd:c25:c25:94de:737b
1912c19:dd:d9:dd:c25:c25:94de:737c/1272c19:dd:d9:dd:c25:c25:94de:737d
1922c19:dd:d9:dd:c25:c25:94de:737e/1272c19:dd:d9:dd:c25:c25:94de:737f
1932c19:dd:d9:dd:c25:c25:94de:7380/1272c19:dd:d9:dd:c25:c25:94de:7381
1942c19:dd:d9:dd:c25:c25:94de:7382/1272c19:dd:d9:dd:c25:c25:94de:7383
1952c19:dd:d9:dd:c25:c25:94de:7384/1272c19:dd:d9:dd:c25:c25:94de:7385
1962c19:dd:d9:dd:c25:c25:94de:7386/1272c19:dd:d9:dd:c25:c25:94de:7387
1972c19:dd:d9:dd:c25:c25:94de:7388/1272c19:dd:d9:dd:c25:c25:94de:7389
1982c19:dd:d9:dd:c25:c25:94de:738a/1272c19:dd:d9:dd:c25:c25:94de:738b
1992c19:dd:d9:dd:c25:c25:94de:738c/1272c19:dd:d9:dd:c25:c25:94de:738d
2002c19:dd:d9:dd:c25:c25:94de:738e/1272c19:dd:d9:dd:c25:c25:94de:738f
2012c19:dd:d9:dd:c25:c25:94de:7390/1272c19:dd:d9:dd:c25:c25:94de:7391
2022c19:dd:d9:dd:c25:c25:94de:7392/1272c19:dd:d9:dd:c25:c25:94de:7393
2032c19:dd:d9:dd:c25:c25:94de:7394/1272c19:dd:d9:dd:c25:c25:94de:7395
2042c19:dd:d9:dd:c25:c25:94de:7396/1272c19:dd:d9:dd:c25:c25:94de:7397
2052c19:dd:d9:dd:c25:c25:94de:7398/1272c19:dd:d9:dd:c25:c25:94de:7399
2062c19:dd:d9:dd:c25:c25:94de:739a/1272c19:dd:d9:dd:c25:c25:94de:739b
2072c19:dd:d9:dd:c25:c25:94de:739c/1272c19:dd:d9:dd:c25:c25:94de:739d
2082c19:dd:d9:dd:c25:c25:94de:739e/1272c19:dd:d9:dd:c25:c25:94de:739f
2092c19:dd:d9:dd:c25:c25:94de:73a0/1272c19:dd:d9:dd:c25:c25:94de:73a1
2102c19:dd:d9:dd:c25:c25:94de:73a2/1272c19:dd:d9:dd:c25:c25:94de:73a3
2112c19:dd:d9:dd:c25:c25:94de:73a4/1272c19:dd:d9:dd:c25:c25:94de:73a5
2122c19:dd:d9:dd:c25:c25:94de:73a6/1272c19:dd:d9:dd:c25:c25:94de:73a7
2132c19:dd:d9:dd:c25:c25:94de:73a8/1272c19:dd:d9:dd:c25:c25:94de:73a9
2142c19:dd:d9:dd:c25:c25:94de:73aa/1272c19:dd:d9:dd:c25:c25:94de:73ab
2152c19:dd:d9:dd:c25:c25:94de:73ac/1272c19:dd:d9:dd:c25:c25:94de:73ad
2162c19:dd:d9:dd:c25:c25:94de:73ae/1272c19:dd:d9:dd:c25:c25:94de:73af
2172c19:dd:d9:dd:c25:c25:94de:73b0/1272c19:dd:d9:dd:c25:c25:94de:73b1
2182c19:dd:d9:dd:c25:c25:94de:73b2/1272c19:dd:d9:dd:c25:c25:94de:73b3
2192c19:dd:d9:dd:c25:c25:94de:73b4/1272c19:dd:d9:dd:c25:c25:94de:73b5
2202c19:dd:d9:dd:c25:c25:94de:73b6/1272c19:dd:d9:dd:c25:c25:94de:73b7
2212c19:dd:d9:dd:c25:c25:94de:73b8/1272c19:dd:d9:dd:c25:c25:94de:73b9
2222c19:dd:d9:dd:c25:c25:94de:73ba/1272c19:dd:d9:dd:c25:c25:94de:73bb
2232c19:dd:d9:dd:c25:c25:94de:73bc/1272c19:dd:d9:dd:c25:c25:94de:73bd
2242c19:dd:d9:dd:c25:c25:94de:73be/1272c19:dd:d9:dd:c25:c25:94de:73bf
2252c19:dd:d9:dd:c25:c25:94de:73c0/1272c19:dd:d9:dd:c25:c25:94de:73c1
2262c19:dd:d9:dd:c25:c25:94de:73c2/1272c19:dd:d9:dd:c25:c25:94de:73c3
2272c19:dd:d9:dd:c25:c25:94de:73c4/1272c19:dd:d9:dd:c25:c25:94de:73c5
2282c19:dd:d9:dd:c25:c25:94de:73c6/1272c19:dd:d9:dd:c25:c25:94de:73c7
2292c19:dd:d9:dd:c25:c25:94de:73c8/1272c19:dd:d9:dd:c25:c25:94de:73c9
2302c19:dd:d9:dd:c25:c25:94de:73ca/1272c19:dd:d9:dd:c25:c25:94de:73cb
2312c19:dd:d9:dd:c25:c25:94de:73cc/1272c19:dd:d9:dd:c25:c25:94de:73cd
2322c19:dd:d9:dd:c25:c25:94de:73ce/1272c19:dd:d9:dd:c25:c25:94de:73cf
2332c19:dd:d9:dd:c25:c25:94de:73d0/1272c19:dd:d9:dd:c25:c25:94de:73d1
2342c19:dd:d9:dd:c25:c25:94de:73d2/1272c19:dd:d9:dd:c25:c25:94de:73d3
2352c19:dd:d9:dd:c25:c25:94de:73d4/1272c19:dd:d9:dd:c25:c25:94de:73d5
2362c19:dd:d9:dd:c25:c25:94de:73d6/1272c19:dd:d9:dd:c25:c25:94de:73d7
2372c19:dd:d9:dd:c25:c25:94de:73d8/1272c19:dd:d9:dd:c25:c25:94de:73d9
2382c19:dd:d9:dd:c25:c25:94de:73da/1272c19:dd:d9:dd:c25:c25:94de:73db
2392c19:dd:d9:dd:c25:c25:94de:73dc/1272c19:dd:d9:dd:c25:c25:94de:73dd
2402c19:dd:d9:dd:c25:c25:94de:73de/1272c19:dd:d9:dd:c25:c25:94de:73df
2412c19:dd:d9:dd:c25:c25:94de:73e0/1272c19:dd:d9:dd:c25:c25:94de:73e1
2422c19:dd:d9:dd:c25:c25:94de:73e2/1272c19:dd:d9:dd:c25:c25:94de:73e3
2432c19:dd:d9:dd:c25:c25:94de:73e4/1272c19:dd:d9:dd:c25:c25:94de:73e5
2442c19:dd:d9:dd:c25:c25:94de:73e6/1272c19:dd:d9:dd:c25:c25:94de:73e7
2452c19:dd:d9:dd:c25:c25:94de:73e8/1272c19:dd:d9:dd:c25:c25:94de:73e9
2462c19:dd:d9:dd:c25:c25:94de:73ea/1272c19:dd:d9:dd:c25:c25:94de:73eb
2472c19:dd:d9:dd:c25:c25:94de:73ec/1272c19:dd:d9:dd:c25:c25:94de:73ed
2482c19:dd:d9:dd:c25:c25:94de:73ee/1272c19:dd:d9:dd:c25:c25:94de:73ef
2492c19:dd:d9:dd:c25:c25:94de:73f0/1272c19:dd:d9:dd:c25:c25:94de:73f1
2502c19:dd:d9:dd:c25:c25:94de:73f2/1272c19:dd:d9:dd:c25:c25:94de:73f3
2512c19:dd:d9:dd:c25:c25:94de:73f4/1272c19:dd:d9:dd:c25:c25:94de:73f5
2522c19:dd:d9:dd:c25:c25:94de:73f6/1272c19:dd:d9:dd:c25:c25:94de:73f7
2532c19:dd:d9:dd:c25:c25:94de:73f8/1272c19:dd:d9:dd:c25:c25:94de:73f9
2542c19:dd:d9:dd:c25:c25:94de:73fa/1272c19:dd:d9:dd:c25:c25:94de:73fb
2552c19:dd:d9:dd:c25:c25:94de:73fc/1272c19:dd:d9:dd:c25:c25:94de:73fd
2562c19:dd:d9:dd:c25:c25:94de:73fe/1272c19:dd:d9:dd:c25:c25:94de:73ff

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.