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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:1200/119
First address
2c19:dd:d9:dd:c25:c25:94de:1200
Last address
2c19:dd:d9:dd:c25:c25:94de:13ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:1200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
2.1.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
3.1.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:1200/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:1200/1272c19:dd:d9:dd:c25:c25:94de:1201
22c19:dd:d9:dd:c25:c25:94de:1202/1272c19:dd:d9:dd:c25:c25:94de:1203
32c19:dd:d9:dd:c25:c25:94de:1204/1272c19:dd:d9:dd:c25:c25:94de:1205
42c19:dd:d9:dd:c25:c25:94de:1206/1272c19:dd:d9:dd:c25:c25:94de:1207
52c19:dd:d9:dd:c25:c25:94de:1208/1272c19:dd:d9:dd:c25:c25:94de:1209
62c19:dd:d9:dd:c25:c25:94de:120a/1272c19:dd:d9:dd:c25:c25:94de:120b
72c19:dd:d9:dd:c25:c25:94de:120c/1272c19:dd:d9:dd:c25:c25:94de:120d
82c19:dd:d9:dd:c25:c25:94de:120e/1272c19:dd:d9:dd:c25:c25:94de:120f
92c19:dd:d9:dd:c25:c25:94de:1210/1272c19:dd:d9:dd:c25:c25:94de:1211
102c19:dd:d9:dd:c25:c25:94de:1212/1272c19:dd:d9:dd:c25:c25:94de:1213
112c19:dd:d9:dd:c25:c25:94de:1214/1272c19:dd:d9:dd:c25:c25:94de:1215
122c19:dd:d9:dd:c25:c25:94de:1216/1272c19:dd:d9:dd:c25:c25:94de:1217
132c19:dd:d9:dd:c25:c25:94de:1218/1272c19:dd:d9:dd:c25:c25:94de:1219
142c19:dd:d9:dd:c25:c25:94de:121a/1272c19:dd:d9:dd:c25:c25:94de:121b
152c19:dd:d9:dd:c25:c25:94de:121c/1272c19:dd:d9:dd:c25:c25:94de:121d
162c19:dd:d9:dd:c25:c25:94de:121e/1272c19:dd:d9:dd:c25:c25:94de:121f
172c19:dd:d9:dd:c25:c25:94de:1220/1272c19:dd:d9:dd:c25:c25:94de:1221
182c19:dd:d9:dd:c25:c25:94de:1222/1272c19:dd:d9:dd:c25:c25:94de:1223
192c19:dd:d9:dd:c25:c25:94de:1224/1272c19:dd:d9:dd:c25:c25:94de:1225
202c19:dd:d9:dd:c25:c25:94de:1226/1272c19:dd:d9:dd:c25:c25:94de:1227
212c19:dd:d9:dd:c25:c25:94de:1228/1272c19:dd:d9:dd:c25:c25:94de:1229
222c19:dd:d9:dd:c25:c25:94de:122a/1272c19:dd:d9:dd:c25:c25:94de:122b
232c19:dd:d9:dd:c25:c25:94de:122c/1272c19:dd:d9:dd:c25:c25:94de:122d
242c19:dd:d9:dd:c25:c25:94de:122e/1272c19:dd:d9:dd:c25:c25:94de:122f
252c19:dd:d9:dd:c25:c25:94de:1230/1272c19:dd:d9:dd:c25:c25:94de:1231
262c19:dd:d9:dd:c25:c25:94de:1232/1272c19:dd:d9:dd:c25:c25:94de:1233
272c19:dd:d9:dd:c25:c25:94de:1234/1272c19:dd:d9:dd:c25:c25:94de:1235
282c19:dd:d9:dd:c25:c25:94de:1236/1272c19:dd:d9:dd:c25:c25:94de:1237
292c19:dd:d9:dd:c25:c25:94de:1238/1272c19:dd:d9:dd:c25:c25:94de:1239
302c19:dd:d9:dd:c25:c25:94de:123a/1272c19:dd:d9:dd:c25:c25:94de:123b
312c19:dd:d9:dd:c25:c25:94de:123c/1272c19:dd:d9:dd:c25:c25:94de:123d
322c19:dd:d9:dd:c25:c25:94de:123e/1272c19:dd:d9:dd:c25:c25:94de:123f
332c19:dd:d9:dd:c25:c25:94de:1240/1272c19:dd:d9:dd:c25:c25:94de:1241
342c19:dd:d9:dd:c25:c25:94de:1242/1272c19:dd:d9:dd:c25:c25:94de:1243
352c19:dd:d9:dd:c25:c25:94de:1244/1272c19:dd:d9:dd:c25:c25:94de:1245
362c19:dd:d9:dd:c25:c25:94de:1246/1272c19:dd:d9:dd:c25:c25:94de:1247
372c19:dd:d9:dd:c25:c25:94de:1248/1272c19:dd:d9:dd:c25:c25:94de:1249
382c19:dd:d9:dd:c25:c25:94de:124a/1272c19:dd:d9:dd:c25:c25:94de:124b
392c19:dd:d9:dd:c25:c25:94de:124c/1272c19:dd:d9:dd:c25:c25:94de:124d
402c19:dd:d9:dd:c25:c25:94de:124e/1272c19:dd:d9:dd:c25:c25:94de:124f
412c19:dd:d9:dd:c25:c25:94de:1250/1272c19:dd:d9:dd:c25:c25:94de:1251
422c19:dd:d9:dd:c25:c25:94de:1252/1272c19:dd:d9:dd:c25:c25:94de:1253
432c19:dd:d9:dd:c25:c25:94de:1254/1272c19:dd:d9:dd:c25:c25:94de:1255
442c19:dd:d9:dd:c25:c25:94de:1256/1272c19:dd:d9:dd:c25:c25:94de:1257
452c19:dd:d9:dd:c25:c25:94de:1258/1272c19:dd:d9:dd:c25:c25:94de:1259
462c19:dd:d9:dd:c25:c25:94de:125a/1272c19:dd:d9:dd:c25:c25:94de:125b
472c19:dd:d9:dd:c25:c25:94de:125c/1272c19:dd:d9:dd:c25:c25:94de:125d
482c19:dd:d9:dd:c25:c25:94de:125e/1272c19:dd:d9:dd:c25:c25:94de:125f
492c19:dd:d9:dd:c25:c25:94de:1260/1272c19:dd:d9:dd:c25:c25:94de:1261
502c19:dd:d9:dd:c25:c25:94de:1262/1272c19:dd:d9:dd:c25:c25:94de:1263
512c19:dd:d9:dd:c25:c25:94de:1264/1272c19:dd:d9:dd:c25:c25:94de:1265
522c19:dd:d9:dd:c25:c25:94de:1266/1272c19:dd:d9:dd:c25:c25:94de:1267
532c19:dd:d9:dd:c25:c25:94de:1268/1272c19:dd:d9:dd:c25:c25:94de:1269
542c19:dd:d9:dd:c25:c25:94de:126a/1272c19:dd:d9:dd:c25:c25:94de:126b
552c19:dd:d9:dd:c25:c25:94de:126c/1272c19:dd:d9:dd:c25:c25:94de:126d
562c19:dd:d9:dd:c25:c25:94de:126e/1272c19:dd:d9:dd:c25:c25:94de:126f
572c19:dd:d9:dd:c25:c25:94de:1270/1272c19:dd:d9:dd:c25:c25:94de:1271
582c19:dd:d9:dd:c25:c25:94de:1272/1272c19:dd:d9:dd:c25:c25:94de:1273
592c19:dd:d9:dd:c25:c25:94de:1274/1272c19:dd:d9:dd:c25:c25:94de:1275
602c19:dd:d9:dd:c25:c25:94de:1276/1272c19:dd:d9:dd:c25:c25:94de:1277
612c19:dd:d9:dd:c25:c25:94de:1278/1272c19:dd:d9:dd:c25:c25:94de:1279
622c19:dd:d9:dd:c25:c25:94de:127a/1272c19:dd:d9:dd:c25:c25:94de:127b
632c19:dd:d9:dd:c25:c25:94de:127c/1272c19:dd:d9:dd:c25:c25:94de:127d
642c19:dd:d9:dd:c25:c25:94de:127e/1272c19:dd:d9:dd:c25:c25:94de:127f
652c19:dd:d9:dd:c25:c25:94de:1280/1272c19:dd:d9:dd:c25:c25:94de:1281
662c19:dd:d9:dd:c25:c25:94de:1282/1272c19:dd:d9:dd:c25:c25:94de:1283
672c19:dd:d9:dd:c25:c25:94de:1284/1272c19:dd:d9:dd:c25:c25:94de:1285
682c19:dd:d9:dd:c25:c25:94de:1286/1272c19:dd:d9:dd:c25:c25:94de:1287
692c19:dd:d9:dd:c25:c25:94de:1288/1272c19:dd:d9:dd:c25:c25:94de:1289
702c19:dd:d9:dd:c25:c25:94de:128a/1272c19:dd:d9:dd:c25:c25:94de:128b
712c19:dd:d9:dd:c25:c25:94de:128c/1272c19:dd:d9:dd:c25:c25:94de:128d
722c19:dd:d9:dd:c25:c25:94de:128e/1272c19:dd:d9:dd:c25:c25:94de:128f
732c19:dd:d9:dd:c25:c25:94de:1290/1272c19:dd:d9:dd:c25:c25:94de:1291
742c19:dd:d9:dd:c25:c25:94de:1292/1272c19:dd:d9:dd:c25:c25:94de:1293
752c19:dd:d9:dd:c25:c25:94de:1294/1272c19:dd:d9:dd:c25:c25:94de:1295
762c19:dd:d9:dd:c25:c25:94de:1296/1272c19:dd:d9:dd:c25:c25:94de:1297
772c19:dd:d9:dd:c25:c25:94de:1298/1272c19:dd:d9:dd:c25:c25:94de:1299
782c19:dd:d9:dd:c25:c25:94de:129a/1272c19:dd:d9:dd:c25:c25:94de:129b
792c19:dd:d9:dd:c25:c25:94de:129c/1272c19:dd:d9:dd:c25:c25:94de:129d
802c19:dd:d9:dd:c25:c25:94de:129e/1272c19:dd:d9:dd:c25:c25:94de:129f
812c19:dd:d9:dd:c25:c25:94de:12a0/1272c19:dd:d9:dd:c25:c25:94de:12a1
822c19:dd:d9:dd:c25:c25:94de:12a2/1272c19:dd:d9:dd:c25:c25:94de:12a3
832c19:dd:d9:dd:c25:c25:94de:12a4/1272c19:dd:d9:dd:c25:c25:94de:12a5
842c19:dd:d9:dd:c25:c25:94de:12a6/1272c19:dd:d9:dd:c25:c25:94de:12a7
852c19:dd:d9:dd:c25:c25:94de:12a8/1272c19:dd:d9:dd:c25:c25:94de:12a9
862c19:dd:d9:dd:c25:c25:94de:12aa/1272c19:dd:d9:dd:c25:c25:94de:12ab
872c19:dd:d9:dd:c25:c25:94de:12ac/1272c19:dd:d9:dd:c25:c25:94de:12ad
882c19:dd:d9:dd:c25:c25:94de:12ae/1272c19:dd:d9:dd:c25:c25:94de:12af
892c19:dd:d9:dd:c25:c25:94de:12b0/1272c19:dd:d9:dd:c25:c25:94de:12b1
902c19:dd:d9:dd:c25:c25:94de:12b2/1272c19:dd:d9:dd:c25:c25:94de:12b3
912c19:dd:d9:dd:c25:c25:94de:12b4/1272c19:dd:d9:dd:c25:c25:94de:12b5
922c19:dd:d9:dd:c25:c25:94de:12b6/1272c19:dd:d9:dd:c25:c25:94de:12b7
932c19:dd:d9:dd:c25:c25:94de:12b8/1272c19:dd:d9:dd:c25:c25:94de:12b9
942c19:dd:d9:dd:c25:c25:94de:12ba/1272c19:dd:d9:dd:c25:c25:94de:12bb
952c19:dd:d9:dd:c25:c25:94de:12bc/1272c19:dd:d9:dd:c25:c25:94de:12bd
962c19:dd:d9:dd:c25:c25:94de:12be/1272c19:dd:d9:dd:c25:c25:94de:12bf
972c19:dd:d9:dd:c25:c25:94de:12c0/1272c19:dd:d9:dd:c25:c25:94de:12c1
982c19:dd:d9:dd:c25:c25:94de:12c2/1272c19:dd:d9:dd:c25:c25:94de:12c3
992c19:dd:d9:dd:c25:c25:94de:12c4/1272c19:dd:d9:dd:c25:c25:94de:12c5
1002c19:dd:d9:dd:c25:c25:94de:12c6/1272c19:dd:d9:dd:c25:c25:94de:12c7
1012c19:dd:d9:dd:c25:c25:94de:12c8/1272c19:dd:d9:dd:c25:c25:94de:12c9
1022c19:dd:d9:dd:c25:c25:94de:12ca/1272c19:dd:d9:dd:c25:c25:94de:12cb
1032c19:dd:d9:dd:c25:c25:94de:12cc/1272c19:dd:d9:dd:c25:c25:94de:12cd
1042c19:dd:d9:dd:c25:c25:94de:12ce/1272c19:dd:d9:dd:c25:c25:94de:12cf
1052c19:dd:d9:dd:c25:c25:94de:12d0/1272c19:dd:d9:dd:c25:c25:94de:12d1
1062c19:dd:d9:dd:c25:c25:94de:12d2/1272c19:dd:d9:dd:c25:c25:94de:12d3
1072c19:dd:d9:dd:c25:c25:94de:12d4/1272c19:dd:d9:dd:c25:c25:94de:12d5
1082c19:dd:d9:dd:c25:c25:94de:12d6/1272c19:dd:d9:dd:c25:c25:94de:12d7
1092c19:dd:d9:dd:c25:c25:94de:12d8/1272c19:dd:d9:dd:c25:c25:94de:12d9
1102c19:dd:d9:dd:c25:c25:94de:12da/1272c19:dd:d9:dd:c25:c25:94de:12db
1112c19:dd:d9:dd:c25:c25:94de:12dc/1272c19:dd:d9:dd:c25:c25:94de:12dd
1122c19:dd:d9:dd:c25:c25:94de:12de/1272c19:dd:d9:dd:c25:c25:94de:12df
1132c19:dd:d9:dd:c25:c25:94de:12e0/1272c19:dd:d9:dd:c25:c25:94de:12e1
1142c19:dd:d9:dd:c25:c25:94de:12e2/1272c19:dd:d9:dd:c25:c25:94de:12e3
1152c19:dd:d9:dd:c25:c25:94de:12e4/1272c19:dd:d9:dd:c25:c25:94de:12e5
1162c19:dd:d9:dd:c25:c25:94de:12e6/1272c19:dd:d9:dd:c25:c25:94de:12e7
1172c19:dd:d9:dd:c25:c25:94de:12e8/1272c19:dd:d9:dd:c25:c25:94de:12e9
1182c19:dd:d9:dd:c25:c25:94de:12ea/1272c19:dd:d9:dd:c25:c25:94de:12eb
1192c19:dd:d9:dd:c25:c25:94de:12ec/1272c19:dd:d9:dd:c25:c25:94de:12ed
1202c19:dd:d9:dd:c25:c25:94de:12ee/1272c19:dd:d9:dd:c25:c25:94de:12ef
1212c19:dd:d9:dd:c25:c25:94de:12f0/1272c19:dd:d9:dd:c25:c25:94de:12f1
1222c19:dd:d9:dd:c25:c25:94de:12f2/1272c19:dd:d9:dd:c25:c25:94de:12f3
1232c19:dd:d9:dd:c25:c25:94de:12f4/1272c19:dd:d9:dd:c25:c25:94de:12f5
1242c19:dd:d9:dd:c25:c25:94de:12f6/1272c19:dd:d9:dd:c25:c25:94de:12f7
1252c19:dd:d9:dd:c25:c25:94de:12f8/1272c19:dd:d9:dd:c25:c25:94de:12f9
1262c19:dd:d9:dd:c25:c25:94de:12fa/1272c19:dd:d9:dd:c25:c25:94de:12fb
1272c19:dd:d9:dd:c25:c25:94de:12fc/1272c19:dd:d9:dd:c25:c25:94de:12fd
1282c19:dd:d9:dd:c25:c25:94de:12fe/1272c19:dd:d9:dd:c25:c25:94de:12ff
1292c19:dd:d9:dd:c25:c25:94de:1300/1272c19:dd:d9:dd:c25:c25:94de:1301
1302c19:dd:d9:dd:c25:c25:94de:1302/1272c19:dd:d9:dd:c25:c25:94de:1303
1312c19:dd:d9:dd:c25:c25:94de:1304/1272c19:dd:d9:dd:c25:c25:94de:1305
1322c19:dd:d9:dd:c25:c25:94de:1306/1272c19:dd:d9:dd:c25:c25:94de:1307
1332c19:dd:d9:dd:c25:c25:94de:1308/1272c19:dd:d9:dd:c25:c25:94de:1309
1342c19:dd:d9:dd:c25:c25:94de:130a/1272c19:dd:d9:dd:c25:c25:94de:130b
1352c19:dd:d9:dd:c25:c25:94de:130c/1272c19:dd:d9:dd:c25:c25:94de:130d
1362c19:dd:d9:dd:c25:c25:94de:130e/1272c19:dd:d9:dd:c25:c25:94de:130f
1372c19:dd:d9:dd:c25:c25:94de:1310/1272c19:dd:d9:dd:c25:c25:94de:1311
1382c19:dd:d9:dd:c25:c25:94de:1312/1272c19:dd:d9:dd:c25:c25:94de:1313
1392c19:dd:d9:dd:c25:c25:94de:1314/1272c19:dd:d9:dd:c25:c25:94de:1315
1402c19:dd:d9:dd:c25:c25:94de:1316/1272c19:dd:d9:dd:c25:c25:94de:1317
1412c19:dd:d9:dd:c25:c25:94de:1318/1272c19:dd:d9:dd:c25:c25:94de:1319
1422c19:dd:d9:dd:c25:c25:94de:131a/1272c19:dd:d9:dd:c25:c25:94de:131b
1432c19:dd:d9:dd:c25:c25:94de:131c/1272c19:dd:d9:dd:c25:c25:94de:131d
1442c19:dd:d9:dd:c25:c25:94de:131e/1272c19:dd:d9:dd:c25:c25:94de:131f
1452c19:dd:d9:dd:c25:c25:94de:1320/1272c19:dd:d9:dd:c25:c25:94de:1321
1462c19:dd:d9:dd:c25:c25:94de:1322/1272c19:dd:d9:dd:c25:c25:94de:1323
1472c19:dd:d9:dd:c25:c25:94de:1324/1272c19:dd:d9:dd:c25:c25:94de:1325
1482c19:dd:d9:dd:c25:c25:94de:1326/1272c19:dd:d9:dd:c25:c25:94de:1327
1492c19:dd:d9:dd:c25:c25:94de:1328/1272c19:dd:d9:dd:c25:c25:94de:1329
1502c19:dd:d9:dd:c25:c25:94de:132a/1272c19:dd:d9:dd:c25:c25:94de:132b
1512c19:dd:d9:dd:c25:c25:94de:132c/1272c19:dd:d9:dd:c25:c25:94de:132d
1522c19:dd:d9:dd:c25:c25:94de:132e/1272c19:dd:d9:dd:c25:c25:94de:132f
1532c19:dd:d9:dd:c25:c25:94de:1330/1272c19:dd:d9:dd:c25:c25:94de:1331
1542c19:dd:d9:dd:c25:c25:94de:1332/1272c19:dd:d9:dd:c25:c25:94de:1333
1552c19:dd:d9:dd:c25:c25:94de:1334/1272c19:dd:d9:dd:c25:c25:94de:1335
1562c19:dd:d9:dd:c25:c25:94de:1336/1272c19:dd:d9:dd:c25:c25:94de:1337
1572c19:dd:d9:dd:c25:c25:94de:1338/1272c19:dd:d9:dd:c25:c25:94de:1339
1582c19:dd:d9:dd:c25:c25:94de:133a/1272c19:dd:d9:dd:c25:c25:94de:133b
1592c19:dd:d9:dd:c25:c25:94de:133c/1272c19:dd:d9:dd:c25:c25:94de:133d
1602c19:dd:d9:dd:c25:c25:94de:133e/1272c19:dd:d9:dd:c25:c25:94de:133f
1612c19:dd:d9:dd:c25:c25:94de:1340/1272c19:dd:d9:dd:c25:c25:94de:1341
1622c19:dd:d9:dd:c25:c25:94de:1342/1272c19:dd:d9:dd:c25:c25:94de:1343
1632c19:dd:d9:dd:c25:c25:94de:1344/1272c19:dd:d9:dd:c25:c25:94de:1345
1642c19:dd:d9:dd:c25:c25:94de:1346/1272c19:dd:d9:dd:c25:c25:94de:1347
1652c19:dd:d9:dd:c25:c25:94de:1348/1272c19:dd:d9:dd:c25:c25:94de:1349
1662c19:dd:d9:dd:c25:c25:94de:134a/1272c19:dd:d9:dd:c25:c25:94de:134b
1672c19:dd:d9:dd:c25:c25:94de:134c/1272c19:dd:d9:dd:c25:c25:94de:134d
1682c19:dd:d9:dd:c25:c25:94de:134e/1272c19:dd:d9:dd:c25:c25:94de:134f
1692c19:dd:d9:dd:c25:c25:94de:1350/1272c19:dd:d9:dd:c25:c25:94de:1351
1702c19:dd:d9:dd:c25:c25:94de:1352/1272c19:dd:d9:dd:c25:c25:94de:1353
1712c19:dd:d9:dd:c25:c25:94de:1354/1272c19:dd:d9:dd:c25:c25:94de:1355
1722c19:dd:d9:dd:c25:c25:94de:1356/1272c19:dd:d9:dd:c25:c25:94de:1357
1732c19:dd:d9:dd:c25:c25:94de:1358/1272c19:dd:d9:dd:c25:c25:94de:1359
1742c19:dd:d9:dd:c25:c25:94de:135a/1272c19:dd:d9:dd:c25:c25:94de:135b
1752c19:dd:d9:dd:c25:c25:94de:135c/1272c19:dd:d9:dd:c25:c25:94de:135d
1762c19:dd:d9:dd:c25:c25:94de:135e/1272c19:dd:d9:dd:c25:c25:94de:135f
1772c19:dd:d9:dd:c25:c25:94de:1360/1272c19:dd:d9:dd:c25:c25:94de:1361
1782c19:dd:d9:dd:c25:c25:94de:1362/1272c19:dd:d9:dd:c25:c25:94de:1363
1792c19:dd:d9:dd:c25:c25:94de:1364/1272c19:dd:d9:dd:c25:c25:94de:1365
1802c19:dd:d9:dd:c25:c25:94de:1366/1272c19:dd:d9:dd:c25:c25:94de:1367
1812c19:dd:d9:dd:c25:c25:94de:1368/1272c19:dd:d9:dd:c25:c25:94de:1369
1822c19:dd:d9:dd:c25:c25:94de:136a/1272c19:dd:d9:dd:c25:c25:94de:136b
1832c19:dd:d9:dd:c25:c25:94de:136c/1272c19:dd:d9:dd:c25:c25:94de:136d
1842c19:dd:d9:dd:c25:c25:94de:136e/1272c19:dd:d9:dd:c25:c25:94de:136f
1852c19:dd:d9:dd:c25:c25:94de:1370/1272c19:dd:d9:dd:c25:c25:94de:1371
1862c19:dd:d9:dd:c25:c25:94de:1372/1272c19:dd:d9:dd:c25:c25:94de:1373
1872c19:dd:d9:dd:c25:c25:94de:1374/1272c19:dd:d9:dd:c25:c25:94de:1375
1882c19:dd:d9:dd:c25:c25:94de:1376/1272c19:dd:d9:dd:c25:c25:94de:1377
1892c19:dd:d9:dd:c25:c25:94de:1378/1272c19:dd:d9:dd:c25:c25:94de:1379
1902c19:dd:d9:dd:c25:c25:94de:137a/1272c19:dd:d9:dd:c25:c25:94de:137b
1912c19:dd:d9:dd:c25:c25:94de:137c/1272c19:dd:d9:dd:c25:c25:94de:137d
1922c19:dd:d9:dd:c25:c25:94de:137e/1272c19:dd:d9:dd:c25:c25:94de:137f
1932c19:dd:d9:dd:c25:c25:94de:1380/1272c19:dd:d9:dd:c25:c25:94de:1381
1942c19:dd:d9:dd:c25:c25:94de:1382/1272c19:dd:d9:dd:c25:c25:94de:1383
1952c19:dd:d9:dd:c25:c25:94de:1384/1272c19:dd:d9:dd:c25:c25:94de:1385
1962c19:dd:d9:dd:c25:c25:94de:1386/1272c19:dd:d9:dd:c25:c25:94de:1387
1972c19:dd:d9:dd:c25:c25:94de:1388/1272c19:dd:d9:dd:c25:c25:94de:1389
1982c19:dd:d9:dd:c25:c25:94de:138a/1272c19:dd:d9:dd:c25:c25:94de:138b
1992c19:dd:d9:dd:c25:c25:94de:138c/1272c19:dd:d9:dd:c25:c25:94de:138d
2002c19:dd:d9:dd:c25:c25:94de:138e/1272c19:dd:d9:dd:c25:c25:94de:138f
2012c19:dd:d9:dd:c25:c25:94de:1390/1272c19:dd:d9:dd:c25:c25:94de:1391
2022c19:dd:d9:dd:c25:c25:94de:1392/1272c19:dd:d9:dd:c25:c25:94de:1393
2032c19:dd:d9:dd:c25:c25:94de:1394/1272c19:dd:d9:dd:c25:c25:94de:1395
2042c19:dd:d9:dd:c25:c25:94de:1396/1272c19:dd:d9:dd:c25:c25:94de:1397
2052c19:dd:d9:dd:c25:c25:94de:1398/1272c19:dd:d9:dd:c25:c25:94de:1399
2062c19:dd:d9:dd:c25:c25:94de:139a/1272c19:dd:d9:dd:c25:c25:94de:139b
2072c19:dd:d9:dd:c25:c25:94de:139c/1272c19:dd:d9:dd:c25:c25:94de:139d
2082c19:dd:d9:dd:c25:c25:94de:139e/1272c19:dd:d9:dd:c25:c25:94de:139f
2092c19:dd:d9:dd:c25:c25:94de:13a0/1272c19:dd:d9:dd:c25:c25:94de:13a1
2102c19:dd:d9:dd:c25:c25:94de:13a2/1272c19:dd:d9:dd:c25:c25:94de:13a3
2112c19:dd:d9:dd:c25:c25:94de:13a4/1272c19:dd:d9:dd:c25:c25:94de:13a5
2122c19:dd:d9:dd:c25:c25:94de:13a6/1272c19:dd:d9:dd:c25:c25:94de:13a7
2132c19:dd:d9:dd:c25:c25:94de:13a8/1272c19:dd:d9:dd:c25:c25:94de:13a9
2142c19:dd:d9:dd:c25:c25:94de:13aa/1272c19:dd:d9:dd:c25:c25:94de:13ab
2152c19:dd:d9:dd:c25:c25:94de:13ac/1272c19:dd:d9:dd:c25:c25:94de:13ad
2162c19:dd:d9:dd:c25:c25:94de:13ae/1272c19:dd:d9:dd:c25:c25:94de:13af
2172c19:dd:d9:dd:c25:c25:94de:13b0/1272c19:dd:d9:dd:c25:c25:94de:13b1
2182c19:dd:d9:dd:c25:c25:94de:13b2/1272c19:dd:d9:dd:c25:c25:94de:13b3
2192c19:dd:d9:dd:c25:c25:94de:13b4/1272c19:dd:d9:dd:c25:c25:94de:13b5
2202c19:dd:d9:dd:c25:c25:94de:13b6/1272c19:dd:d9:dd:c25:c25:94de:13b7
2212c19:dd:d9:dd:c25:c25:94de:13b8/1272c19:dd:d9:dd:c25:c25:94de:13b9
2222c19:dd:d9:dd:c25:c25:94de:13ba/1272c19:dd:d9:dd:c25:c25:94de:13bb
2232c19:dd:d9:dd:c25:c25:94de:13bc/1272c19:dd:d9:dd:c25:c25:94de:13bd
2242c19:dd:d9:dd:c25:c25:94de:13be/1272c19:dd:d9:dd:c25:c25:94de:13bf
2252c19:dd:d9:dd:c25:c25:94de:13c0/1272c19:dd:d9:dd:c25:c25:94de:13c1
2262c19:dd:d9:dd:c25:c25:94de:13c2/1272c19:dd:d9:dd:c25:c25:94de:13c3
2272c19:dd:d9:dd:c25:c25:94de:13c4/1272c19:dd:d9:dd:c25:c25:94de:13c5
2282c19:dd:d9:dd:c25:c25:94de:13c6/1272c19:dd:d9:dd:c25:c25:94de:13c7
2292c19:dd:d9:dd:c25:c25:94de:13c8/1272c19:dd:d9:dd:c25:c25:94de:13c9
2302c19:dd:d9:dd:c25:c25:94de:13ca/1272c19:dd:d9:dd:c25:c25:94de:13cb
2312c19:dd:d9:dd:c25:c25:94de:13cc/1272c19:dd:d9:dd:c25:c25:94de:13cd
2322c19:dd:d9:dd:c25:c25:94de:13ce/1272c19:dd:d9:dd:c25:c25:94de:13cf
2332c19:dd:d9:dd:c25:c25:94de:13d0/1272c19:dd:d9:dd:c25:c25:94de:13d1
2342c19:dd:d9:dd:c25:c25:94de:13d2/1272c19:dd:d9:dd:c25:c25:94de:13d3
2352c19:dd:d9:dd:c25:c25:94de:13d4/1272c19:dd:d9:dd:c25:c25:94de:13d5
2362c19:dd:d9:dd:c25:c25:94de:13d6/1272c19:dd:d9:dd:c25:c25:94de:13d7
2372c19:dd:d9:dd:c25:c25:94de:13d8/1272c19:dd:d9:dd:c25:c25:94de:13d9
2382c19:dd:d9:dd:c25:c25:94de:13da/1272c19:dd:d9:dd:c25:c25:94de:13db
2392c19:dd:d9:dd:c25:c25:94de:13dc/1272c19:dd:d9:dd:c25:c25:94de:13dd
2402c19:dd:d9:dd:c25:c25:94de:13de/1272c19:dd:d9:dd:c25:c25:94de:13df
2412c19:dd:d9:dd:c25:c25:94de:13e0/1272c19:dd:d9:dd:c25:c25:94de:13e1
2422c19:dd:d9:dd:c25:c25:94de:13e2/1272c19:dd:d9:dd:c25:c25:94de:13e3
2432c19:dd:d9:dd:c25:c25:94de:13e4/1272c19:dd:d9:dd:c25:c25:94de:13e5
2442c19:dd:d9:dd:c25:c25:94de:13e6/1272c19:dd:d9:dd:c25:c25:94de:13e7
2452c19:dd:d9:dd:c25:c25:94de:13e8/1272c19:dd:d9:dd:c25:c25:94de:13e9
2462c19:dd:d9:dd:c25:c25:94de:13ea/1272c19:dd:d9:dd:c25:c25:94de:13eb
2472c19:dd:d9:dd:c25:c25:94de:13ec/1272c19:dd:d9:dd:c25:c25:94de:13ed
2482c19:dd:d9:dd:c25:c25:94de:13ee/1272c19:dd:d9:dd:c25:c25:94de:13ef
2492c19:dd:d9:dd:c25:c25:94de:13f0/1272c19:dd:d9:dd:c25:c25:94de:13f1
2502c19:dd:d9:dd:c25:c25:94de:13f2/1272c19:dd:d9:dd:c25:c25:94de:13f3
2512c19:dd:d9:dd:c25:c25:94de:13f4/1272c19:dd:d9:dd:c25:c25:94de:13f5
2522c19:dd:d9:dd:c25:c25:94de:13f6/1272c19:dd:d9:dd:c25:c25:94de:13f7
2532c19:dd:d9:dd:c25:c25:94de:13f8/1272c19:dd:d9:dd:c25:c25:94de:13f9
2542c19:dd:d9:dd:c25:c25:94de:13fa/1272c19:dd:d9:dd:c25:c25:94de:13fb
2552c19:dd:d9:dd:c25:c25:94de:13fc/1272c19:dd:d9:dd:c25:c25:94de:13fd
2562c19:dd:d9:dd:c25:c25:94de:13fe/1272c19:dd:d9:dd:c25:c25:94de:13ff

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.