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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:d915:1600/119
First address
2c19:dd:d9:dd:c25:c25:d915:1600
Last address
2c19:dd:d9:dd:c25:c25:d915:17ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:1600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.1.5.1.9.d.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
7.1.5.1.9.d.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/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:d915:1600/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:1600/1282c19:dd:d9:dd:c25:c25:d915:1600
22c19:dd:d9:dd:c25:c25:d915:1601/1282c19:dd:d9:dd:c25:c25:d915:1601
32c19:dd:d9:dd:c25:c25:d915:1602/1282c19:dd:d9:dd:c25:c25:d915:1602
42c19:dd:d9:dd:c25:c25:d915:1603/1282c19:dd:d9:dd:c25:c25:d915:1603
52c19:dd:d9:dd:c25:c25:d915:1604/1282c19:dd:d9:dd:c25:c25:d915:1604
62c19:dd:d9:dd:c25:c25:d915:1605/1282c19:dd:d9:dd:c25:c25:d915:1605
72c19:dd:d9:dd:c25:c25:d915:1606/1282c19:dd:d9:dd:c25:c25:d915:1606
82c19:dd:d9:dd:c25:c25:d915:1607/1282c19:dd:d9:dd:c25:c25:d915:1607
92c19:dd:d9:dd:c25:c25:d915:1608/1282c19:dd:d9:dd:c25:c25:d915:1608
102c19:dd:d9:dd:c25:c25:d915:1609/1282c19:dd:d9:dd:c25:c25:d915:1609
112c19:dd:d9:dd:c25:c25:d915:160a/1282c19:dd:d9:dd:c25:c25:d915:160a
122c19:dd:d9:dd:c25:c25:d915:160b/1282c19:dd:d9:dd:c25:c25:d915:160b
132c19:dd:d9:dd:c25:c25:d915:160c/1282c19:dd:d9:dd:c25:c25:d915:160c
142c19:dd:d9:dd:c25:c25:d915:160d/1282c19:dd:d9:dd:c25:c25:d915:160d
152c19:dd:d9:dd:c25:c25:d915:160e/1282c19:dd:d9:dd:c25:c25:d915:160e
162c19:dd:d9:dd:c25:c25:d915:160f/1282c19:dd:d9:dd:c25:c25:d915:160f
172c19:dd:d9:dd:c25:c25:d915:1610/1282c19:dd:d9:dd:c25:c25:d915:1610
182c19:dd:d9:dd:c25:c25:d915:1611/1282c19:dd:d9:dd:c25:c25:d915:1611
192c19:dd:d9:dd:c25:c25:d915:1612/1282c19:dd:d9:dd:c25:c25:d915:1612
202c19:dd:d9:dd:c25:c25:d915:1613/1282c19:dd:d9:dd:c25:c25:d915:1613
212c19:dd:d9:dd:c25:c25:d915:1614/1282c19:dd:d9:dd:c25:c25:d915:1614
222c19:dd:d9:dd:c25:c25:d915:1615/1282c19:dd:d9:dd:c25:c25:d915:1615
232c19:dd:d9:dd:c25:c25:d915:1616/1282c19:dd:d9:dd:c25:c25:d915:1616
242c19:dd:d9:dd:c25:c25:d915:1617/1282c19:dd:d9:dd:c25:c25:d915:1617
252c19:dd:d9:dd:c25:c25:d915:1618/1282c19:dd:d9:dd:c25:c25:d915:1618
262c19:dd:d9:dd:c25:c25:d915:1619/1282c19:dd:d9:dd:c25:c25:d915:1619
272c19:dd:d9:dd:c25:c25:d915:161a/1282c19:dd:d9:dd:c25:c25:d915:161a
282c19:dd:d9:dd:c25:c25:d915:161b/1282c19:dd:d9:dd:c25:c25:d915:161b
292c19:dd:d9:dd:c25:c25:d915:161c/1282c19:dd:d9:dd:c25:c25:d915:161c
302c19:dd:d9:dd:c25:c25:d915:161d/1282c19:dd:d9:dd:c25:c25:d915:161d
312c19:dd:d9:dd:c25:c25:d915:161e/1282c19:dd:d9:dd:c25:c25:d915:161e
322c19:dd:d9:dd:c25:c25:d915:161f/1282c19:dd:d9:dd:c25:c25:d915:161f
332c19:dd:d9:dd:c25:c25:d915:1620/1282c19:dd:d9:dd:c25:c25:d915:1620
342c19:dd:d9:dd:c25:c25:d915:1621/1282c19:dd:d9:dd:c25:c25:d915:1621
352c19:dd:d9:dd:c25:c25:d915:1622/1282c19:dd:d9:dd:c25:c25:d915:1622
362c19:dd:d9:dd:c25:c25:d915:1623/1282c19:dd:d9:dd:c25:c25:d915:1623
372c19:dd:d9:dd:c25:c25:d915:1624/1282c19:dd:d9:dd:c25:c25:d915:1624
382c19:dd:d9:dd:c25:c25:d915:1625/1282c19:dd:d9:dd:c25:c25:d915:1625
392c19:dd:d9:dd:c25:c25:d915:1626/1282c19:dd:d9:dd:c25:c25:d915:1626
402c19:dd:d9:dd:c25:c25:d915:1627/1282c19:dd:d9:dd:c25:c25:d915:1627
412c19:dd:d9:dd:c25:c25:d915:1628/1282c19:dd:d9:dd:c25:c25:d915:1628
422c19:dd:d9:dd:c25:c25:d915:1629/1282c19:dd:d9:dd:c25:c25:d915:1629
432c19:dd:d9:dd:c25:c25:d915:162a/1282c19:dd:d9:dd:c25:c25:d915:162a
442c19:dd:d9:dd:c25:c25:d915:162b/1282c19:dd:d9:dd:c25:c25:d915:162b
452c19:dd:d9:dd:c25:c25:d915:162c/1282c19:dd:d9:dd:c25:c25:d915:162c
462c19:dd:d9:dd:c25:c25:d915:162d/1282c19:dd:d9:dd:c25:c25:d915:162d
472c19:dd:d9:dd:c25:c25:d915:162e/1282c19:dd:d9:dd:c25:c25:d915:162e
482c19:dd:d9:dd:c25:c25:d915:162f/1282c19:dd:d9:dd:c25:c25:d915:162f
492c19:dd:d9:dd:c25:c25:d915:1630/1282c19:dd:d9:dd:c25:c25:d915:1630
502c19:dd:d9:dd:c25:c25:d915:1631/1282c19:dd:d9:dd:c25:c25:d915:1631
512c19:dd:d9:dd:c25:c25:d915:1632/1282c19:dd:d9:dd:c25:c25:d915:1632
522c19:dd:d9:dd:c25:c25:d915:1633/1282c19:dd:d9:dd:c25:c25:d915:1633
532c19:dd:d9:dd:c25:c25:d915:1634/1282c19:dd:d9:dd:c25:c25:d915:1634
542c19:dd:d9:dd:c25:c25:d915:1635/1282c19:dd:d9:dd:c25:c25:d915:1635
552c19:dd:d9:dd:c25:c25:d915:1636/1282c19:dd:d9:dd:c25:c25:d915:1636
562c19:dd:d9:dd:c25:c25:d915:1637/1282c19:dd:d9:dd:c25:c25:d915:1637
572c19:dd:d9:dd:c25:c25:d915:1638/1282c19:dd:d9:dd:c25:c25:d915:1638
582c19:dd:d9:dd:c25:c25:d915:1639/1282c19:dd:d9:dd:c25:c25:d915:1639
592c19:dd:d9:dd:c25:c25:d915:163a/1282c19:dd:d9:dd:c25:c25:d915:163a
602c19:dd:d9:dd:c25:c25:d915:163b/1282c19:dd:d9:dd:c25:c25:d915:163b
612c19:dd:d9:dd:c25:c25:d915:163c/1282c19:dd:d9:dd:c25:c25:d915:163c
622c19:dd:d9:dd:c25:c25:d915:163d/1282c19:dd:d9:dd:c25:c25:d915:163d
632c19:dd:d9:dd:c25:c25:d915:163e/1282c19:dd:d9:dd:c25:c25:d915:163e
642c19:dd:d9:dd:c25:c25:d915:163f/1282c19:dd:d9:dd:c25:c25:d915:163f
652c19:dd:d9:dd:c25:c25:d915:1640/1282c19:dd:d9:dd:c25:c25:d915:1640
662c19:dd:d9:dd:c25:c25:d915:1641/1282c19:dd:d9:dd:c25:c25:d915:1641
672c19:dd:d9:dd:c25:c25:d915:1642/1282c19:dd:d9:dd:c25:c25:d915:1642
682c19:dd:d9:dd:c25:c25:d915:1643/1282c19:dd:d9:dd:c25:c25:d915:1643
692c19:dd:d9:dd:c25:c25:d915:1644/1282c19:dd:d9:dd:c25:c25:d915:1644
702c19:dd:d9:dd:c25:c25:d915:1645/1282c19:dd:d9:dd:c25:c25:d915:1645
712c19:dd:d9:dd:c25:c25:d915:1646/1282c19:dd:d9:dd:c25:c25:d915:1646
722c19:dd:d9:dd:c25:c25:d915:1647/1282c19:dd:d9:dd:c25:c25:d915:1647
732c19:dd:d9:dd:c25:c25:d915:1648/1282c19:dd:d9:dd:c25:c25:d915:1648
742c19:dd:d9:dd:c25:c25:d915:1649/1282c19:dd:d9:dd:c25:c25:d915:1649
752c19:dd:d9:dd:c25:c25:d915:164a/1282c19:dd:d9:dd:c25:c25:d915:164a
762c19:dd:d9:dd:c25:c25:d915:164b/1282c19:dd:d9:dd:c25:c25:d915:164b
772c19:dd:d9:dd:c25:c25:d915:164c/1282c19:dd:d9:dd:c25:c25:d915:164c
782c19:dd:d9:dd:c25:c25:d915:164d/1282c19:dd:d9:dd:c25:c25:d915:164d
792c19:dd:d9:dd:c25:c25:d915:164e/1282c19:dd:d9:dd:c25:c25:d915:164e
802c19:dd:d9:dd:c25:c25:d915:164f/1282c19:dd:d9:dd:c25:c25:d915:164f
812c19:dd:d9:dd:c25:c25:d915:1650/1282c19:dd:d9:dd:c25:c25:d915:1650
822c19:dd:d9:dd:c25:c25:d915:1651/1282c19:dd:d9:dd:c25:c25:d915:1651
832c19:dd:d9:dd:c25:c25:d915:1652/1282c19:dd:d9:dd:c25:c25:d915:1652
842c19:dd:d9:dd:c25:c25:d915:1653/1282c19:dd:d9:dd:c25:c25:d915:1653
852c19:dd:d9:dd:c25:c25:d915:1654/1282c19:dd:d9:dd:c25:c25:d915:1654
862c19:dd:d9:dd:c25:c25:d915:1655/1282c19:dd:d9:dd:c25:c25:d915:1655
872c19:dd:d9:dd:c25:c25:d915:1656/1282c19:dd:d9:dd:c25:c25:d915:1656
882c19:dd:d9:dd:c25:c25:d915:1657/1282c19:dd:d9:dd:c25:c25:d915:1657
892c19:dd:d9:dd:c25:c25:d915:1658/1282c19:dd:d9:dd:c25:c25:d915:1658
902c19:dd:d9:dd:c25:c25:d915:1659/1282c19:dd:d9:dd:c25:c25:d915:1659
912c19:dd:d9:dd:c25:c25:d915:165a/1282c19:dd:d9:dd:c25:c25:d915:165a
922c19:dd:d9:dd:c25:c25:d915:165b/1282c19:dd:d9:dd:c25:c25:d915:165b
932c19:dd:d9:dd:c25:c25:d915:165c/1282c19:dd:d9:dd:c25:c25:d915:165c
942c19:dd:d9:dd:c25:c25:d915:165d/1282c19:dd:d9:dd:c25:c25:d915:165d
952c19:dd:d9:dd:c25:c25:d915:165e/1282c19:dd:d9:dd:c25:c25:d915:165e
962c19:dd:d9:dd:c25:c25:d915:165f/1282c19:dd:d9:dd:c25:c25:d915:165f
972c19:dd:d9:dd:c25:c25:d915:1660/1282c19:dd:d9:dd:c25:c25:d915:1660
982c19:dd:d9:dd:c25:c25:d915:1661/1282c19:dd:d9:dd:c25:c25:d915:1661
992c19:dd:d9:dd:c25:c25:d915:1662/1282c19:dd:d9:dd:c25:c25:d915:1662
1002c19:dd:d9:dd:c25:c25:d915:1663/1282c19:dd:d9:dd:c25:c25:d915:1663
1012c19:dd:d9:dd:c25:c25:d915:1664/1282c19:dd:d9:dd:c25:c25:d915:1664
1022c19:dd:d9:dd:c25:c25:d915:1665/1282c19:dd:d9:dd:c25:c25:d915:1665
1032c19:dd:d9:dd:c25:c25:d915:1666/1282c19:dd:d9:dd:c25:c25:d915:1666
1042c19:dd:d9:dd:c25:c25:d915:1667/1282c19:dd:d9:dd:c25:c25:d915:1667
1052c19:dd:d9:dd:c25:c25:d915:1668/1282c19:dd:d9:dd:c25:c25:d915:1668
1062c19:dd:d9:dd:c25:c25:d915:1669/1282c19:dd:d9:dd:c25:c25:d915:1669
1072c19:dd:d9:dd:c25:c25:d915:166a/1282c19:dd:d9:dd:c25:c25:d915:166a
1082c19:dd:d9:dd:c25:c25:d915:166b/1282c19:dd:d9:dd:c25:c25:d915:166b
1092c19:dd:d9:dd:c25:c25:d915:166c/1282c19:dd:d9:dd:c25:c25:d915:166c
1102c19:dd:d9:dd:c25:c25:d915:166d/1282c19:dd:d9:dd:c25:c25:d915:166d
1112c19:dd:d9:dd:c25:c25:d915:166e/1282c19:dd:d9:dd:c25:c25:d915:166e
1122c19:dd:d9:dd:c25:c25:d915:166f/1282c19:dd:d9:dd:c25:c25:d915:166f
1132c19:dd:d9:dd:c25:c25:d915:1670/1282c19:dd:d9:dd:c25:c25:d915:1670
1142c19:dd:d9:dd:c25:c25:d915:1671/1282c19:dd:d9:dd:c25:c25:d915:1671
1152c19:dd:d9:dd:c25:c25:d915:1672/1282c19:dd:d9:dd:c25:c25:d915:1672
1162c19:dd:d9:dd:c25:c25:d915:1673/1282c19:dd:d9:dd:c25:c25:d915:1673
1172c19:dd:d9:dd:c25:c25:d915:1674/1282c19:dd:d9:dd:c25:c25:d915:1674
1182c19:dd:d9:dd:c25:c25:d915:1675/1282c19:dd:d9:dd:c25:c25:d915:1675
1192c19:dd:d9:dd:c25:c25:d915:1676/1282c19:dd:d9:dd:c25:c25:d915:1676
1202c19:dd:d9:dd:c25:c25:d915:1677/1282c19:dd:d9:dd:c25:c25:d915:1677
1212c19:dd:d9:dd:c25:c25:d915:1678/1282c19:dd:d9:dd:c25:c25:d915:1678
1222c19:dd:d9:dd:c25:c25:d915:1679/1282c19:dd:d9:dd:c25:c25:d915:1679
1232c19:dd:d9:dd:c25:c25:d915:167a/1282c19:dd:d9:dd:c25:c25:d915:167a
1242c19:dd:d9:dd:c25:c25:d915:167b/1282c19:dd:d9:dd:c25:c25:d915:167b
1252c19:dd:d9:dd:c25:c25:d915:167c/1282c19:dd:d9:dd:c25:c25:d915:167c
1262c19:dd:d9:dd:c25:c25:d915:167d/1282c19:dd:d9:dd:c25:c25:d915:167d
1272c19:dd:d9:dd:c25:c25:d915:167e/1282c19:dd:d9:dd:c25:c25:d915:167e
1282c19:dd:d9:dd:c25:c25:d915:167f/1282c19:dd:d9:dd:c25:c25:d915:167f
1292c19:dd:d9:dd:c25:c25:d915:1680/1282c19:dd:d9:dd:c25:c25:d915:1680
1302c19:dd:d9:dd:c25:c25:d915:1681/1282c19:dd:d9:dd:c25:c25:d915:1681
1312c19:dd:d9:dd:c25:c25:d915:1682/1282c19:dd:d9:dd:c25:c25:d915:1682
1322c19:dd:d9:dd:c25:c25:d915:1683/1282c19:dd:d9:dd:c25:c25:d915:1683
1332c19:dd:d9:dd:c25:c25:d915:1684/1282c19:dd:d9:dd:c25:c25:d915:1684
1342c19:dd:d9:dd:c25:c25:d915:1685/1282c19:dd:d9:dd:c25:c25:d915:1685
1352c19:dd:d9:dd:c25:c25:d915:1686/1282c19:dd:d9:dd:c25:c25:d915:1686
1362c19:dd:d9:dd:c25:c25:d915:1687/1282c19:dd:d9:dd:c25:c25:d915:1687
1372c19:dd:d9:dd:c25:c25:d915:1688/1282c19:dd:d9:dd:c25:c25:d915:1688
1382c19:dd:d9:dd:c25:c25:d915:1689/1282c19:dd:d9:dd:c25:c25:d915:1689
1392c19:dd:d9:dd:c25:c25:d915:168a/1282c19:dd:d9:dd:c25:c25:d915:168a
1402c19:dd:d9:dd:c25:c25:d915:168b/1282c19:dd:d9:dd:c25:c25:d915:168b
1412c19:dd:d9:dd:c25:c25:d915:168c/1282c19:dd:d9:dd:c25:c25:d915:168c
1422c19:dd:d9:dd:c25:c25:d915:168d/1282c19:dd:d9:dd:c25:c25:d915:168d
1432c19:dd:d9:dd:c25:c25:d915:168e/1282c19:dd:d9:dd:c25:c25:d915:168e
1442c19:dd:d9:dd:c25:c25:d915:168f/1282c19:dd:d9:dd:c25:c25:d915:168f
1452c19:dd:d9:dd:c25:c25:d915:1690/1282c19:dd:d9:dd:c25:c25:d915:1690
1462c19:dd:d9:dd:c25:c25:d915:1691/1282c19:dd:d9:dd:c25:c25:d915:1691
1472c19:dd:d9:dd:c25:c25:d915:1692/1282c19:dd:d9:dd:c25:c25:d915:1692
1482c19:dd:d9:dd:c25:c25:d915:1693/1282c19:dd:d9:dd:c25:c25:d915:1693
1492c19:dd:d9:dd:c25:c25:d915:1694/1282c19:dd:d9:dd:c25:c25:d915:1694
1502c19:dd:d9:dd:c25:c25:d915:1695/1282c19:dd:d9:dd:c25:c25:d915:1695
1512c19:dd:d9:dd:c25:c25:d915:1696/1282c19:dd:d9:dd:c25:c25:d915:1696
1522c19:dd:d9:dd:c25:c25:d915:1697/1282c19:dd:d9:dd:c25:c25:d915:1697
1532c19:dd:d9:dd:c25:c25:d915:1698/1282c19:dd:d9:dd:c25:c25:d915:1698
1542c19:dd:d9:dd:c25:c25:d915:1699/1282c19:dd:d9:dd:c25:c25:d915:1699
1552c19:dd:d9:dd:c25:c25:d915:169a/1282c19:dd:d9:dd:c25:c25:d915:169a
1562c19:dd:d9:dd:c25:c25:d915:169b/1282c19:dd:d9:dd:c25:c25:d915:169b
1572c19:dd:d9:dd:c25:c25:d915:169c/1282c19:dd:d9:dd:c25:c25:d915:169c
1582c19:dd:d9:dd:c25:c25:d915:169d/1282c19:dd:d9:dd:c25:c25:d915:169d
1592c19:dd:d9:dd:c25:c25:d915:169e/1282c19:dd:d9:dd:c25:c25:d915:169e
1602c19:dd:d9:dd:c25:c25:d915:169f/1282c19:dd:d9:dd:c25:c25:d915:169f
1612c19:dd:d9:dd:c25:c25:d915:16a0/1282c19:dd:d9:dd:c25:c25:d915:16a0
1622c19:dd:d9:dd:c25:c25:d915:16a1/1282c19:dd:d9:dd:c25:c25:d915:16a1
1632c19:dd:d9:dd:c25:c25:d915:16a2/1282c19:dd:d9:dd:c25:c25:d915:16a2
1642c19:dd:d9:dd:c25:c25:d915:16a3/1282c19:dd:d9:dd:c25:c25:d915:16a3
1652c19:dd:d9:dd:c25:c25:d915:16a4/1282c19:dd:d9:dd:c25:c25:d915:16a4
1662c19:dd:d9:dd:c25:c25:d915:16a5/1282c19:dd:d9:dd:c25:c25:d915:16a5
1672c19:dd:d9:dd:c25:c25:d915:16a6/1282c19:dd:d9:dd:c25:c25:d915:16a6
1682c19:dd:d9:dd:c25:c25:d915:16a7/1282c19:dd:d9:dd:c25:c25:d915:16a7
1692c19:dd:d9:dd:c25:c25:d915:16a8/1282c19:dd:d9:dd:c25:c25:d915:16a8
1702c19:dd:d9:dd:c25:c25:d915:16a9/1282c19:dd:d9:dd:c25:c25:d915:16a9
1712c19:dd:d9:dd:c25:c25:d915:16aa/1282c19:dd:d9:dd:c25:c25:d915:16aa
1722c19:dd:d9:dd:c25:c25:d915:16ab/1282c19:dd:d9:dd:c25:c25:d915:16ab
1732c19:dd:d9:dd:c25:c25:d915:16ac/1282c19:dd:d9:dd:c25:c25:d915:16ac
1742c19:dd:d9:dd:c25:c25:d915:16ad/1282c19:dd:d9:dd:c25:c25:d915:16ad
1752c19:dd:d9:dd:c25:c25:d915:16ae/1282c19:dd:d9:dd:c25:c25:d915:16ae
1762c19:dd:d9:dd:c25:c25:d915:16af/1282c19:dd:d9:dd:c25:c25:d915:16af
1772c19:dd:d9:dd:c25:c25:d915:16b0/1282c19:dd:d9:dd:c25:c25:d915:16b0
1782c19:dd:d9:dd:c25:c25:d915:16b1/1282c19:dd:d9:dd:c25:c25:d915:16b1
1792c19:dd:d9:dd:c25:c25:d915:16b2/1282c19:dd:d9:dd:c25:c25:d915:16b2
1802c19:dd:d9:dd:c25:c25:d915:16b3/1282c19:dd:d9:dd:c25:c25:d915:16b3
1812c19:dd:d9:dd:c25:c25:d915:16b4/1282c19:dd:d9:dd:c25:c25:d915:16b4
1822c19:dd:d9:dd:c25:c25:d915:16b5/1282c19:dd:d9:dd:c25:c25:d915:16b5
1832c19:dd:d9:dd:c25:c25:d915:16b6/1282c19:dd:d9:dd:c25:c25:d915:16b6
1842c19:dd:d9:dd:c25:c25:d915:16b7/1282c19:dd:d9:dd:c25:c25:d915:16b7
1852c19:dd:d9:dd:c25:c25:d915:16b8/1282c19:dd:d9:dd:c25:c25:d915:16b8
1862c19:dd:d9:dd:c25:c25:d915:16b9/1282c19:dd:d9:dd:c25:c25:d915:16b9
1872c19:dd:d9:dd:c25:c25:d915:16ba/1282c19:dd:d9:dd:c25:c25:d915:16ba
1882c19:dd:d9:dd:c25:c25:d915:16bb/1282c19:dd:d9:dd:c25:c25:d915:16bb
1892c19:dd:d9:dd:c25:c25:d915:16bc/1282c19:dd:d9:dd:c25:c25:d915:16bc
1902c19:dd:d9:dd:c25:c25:d915:16bd/1282c19:dd:d9:dd:c25:c25:d915:16bd
1912c19:dd:d9:dd:c25:c25:d915:16be/1282c19:dd:d9:dd:c25:c25:d915:16be
1922c19:dd:d9:dd:c25:c25:d915:16bf/1282c19:dd:d9:dd:c25:c25:d915:16bf
1932c19:dd:d9:dd:c25:c25:d915:16c0/1282c19:dd:d9:dd:c25:c25:d915:16c0
1942c19:dd:d9:dd:c25:c25:d915:16c1/1282c19:dd:d9:dd:c25:c25:d915:16c1
1952c19:dd:d9:dd:c25:c25:d915:16c2/1282c19:dd:d9:dd:c25:c25:d915:16c2
1962c19:dd:d9:dd:c25:c25:d915:16c3/1282c19:dd:d9:dd:c25:c25:d915:16c3
1972c19:dd:d9:dd:c25:c25:d915:16c4/1282c19:dd:d9:dd:c25:c25:d915:16c4
1982c19:dd:d9:dd:c25:c25:d915:16c5/1282c19:dd:d9:dd:c25:c25:d915:16c5
1992c19:dd:d9:dd:c25:c25:d915:16c6/1282c19:dd:d9:dd:c25:c25:d915:16c6
2002c19:dd:d9:dd:c25:c25:d915:16c7/1282c19:dd:d9:dd:c25:c25:d915:16c7
2012c19:dd:d9:dd:c25:c25:d915:16c8/1282c19:dd:d9:dd:c25:c25:d915:16c8
2022c19:dd:d9:dd:c25:c25:d915:16c9/1282c19:dd:d9:dd:c25:c25:d915:16c9
2032c19:dd:d9:dd:c25:c25:d915:16ca/1282c19:dd:d9:dd:c25:c25:d915:16ca
2042c19:dd:d9:dd:c25:c25:d915:16cb/1282c19:dd:d9:dd:c25:c25:d915:16cb
2052c19:dd:d9:dd:c25:c25:d915:16cc/1282c19:dd:d9:dd:c25:c25:d915:16cc
2062c19:dd:d9:dd:c25:c25:d915:16cd/1282c19:dd:d9:dd:c25:c25:d915:16cd
2072c19:dd:d9:dd:c25:c25:d915:16ce/1282c19:dd:d9:dd:c25:c25:d915:16ce
2082c19:dd:d9:dd:c25:c25:d915:16cf/1282c19:dd:d9:dd:c25:c25:d915:16cf
2092c19:dd:d9:dd:c25:c25:d915:16d0/1282c19:dd:d9:dd:c25:c25:d915:16d0
2102c19:dd:d9:dd:c25:c25:d915:16d1/1282c19:dd:d9:dd:c25:c25:d915:16d1
2112c19:dd:d9:dd:c25:c25:d915:16d2/1282c19:dd:d9:dd:c25:c25:d915:16d2
2122c19:dd:d9:dd:c25:c25:d915:16d3/1282c19:dd:d9:dd:c25:c25:d915:16d3
2132c19:dd:d9:dd:c25:c25:d915:16d4/1282c19:dd:d9:dd:c25:c25:d915:16d4
2142c19:dd:d9:dd:c25:c25:d915:16d5/1282c19:dd:d9:dd:c25:c25:d915:16d5
2152c19:dd:d9:dd:c25:c25:d915:16d6/1282c19:dd:d9:dd:c25:c25:d915:16d6
2162c19:dd:d9:dd:c25:c25:d915:16d7/1282c19:dd:d9:dd:c25:c25:d915:16d7
2172c19:dd:d9:dd:c25:c25:d915:16d8/1282c19:dd:d9:dd:c25:c25:d915:16d8
2182c19:dd:d9:dd:c25:c25:d915:16d9/1282c19:dd:d9:dd:c25:c25:d915:16d9
2192c19:dd:d9:dd:c25:c25:d915:16da/1282c19:dd:d9:dd:c25:c25:d915:16da
2202c19:dd:d9:dd:c25:c25:d915:16db/1282c19:dd:d9:dd:c25:c25:d915:16db
2212c19:dd:d9:dd:c25:c25:d915:16dc/1282c19:dd:d9:dd:c25:c25:d915:16dc
2222c19:dd:d9:dd:c25:c25:d915:16dd/1282c19:dd:d9:dd:c25:c25:d915:16dd
2232c19:dd:d9:dd:c25:c25:d915:16de/1282c19:dd:d9:dd:c25:c25:d915:16de
2242c19:dd:d9:dd:c25:c25:d915:16df/1282c19:dd:d9:dd:c25:c25:d915:16df
2252c19:dd:d9:dd:c25:c25:d915:16e0/1282c19:dd:d9:dd:c25:c25:d915:16e0
2262c19:dd:d9:dd:c25:c25:d915:16e1/1282c19:dd:d9:dd:c25:c25:d915:16e1
2272c19:dd:d9:dd:c25:c25:d915:16e2/1282c19:dd:d9:dd:c25:c25:d915:16e2
2282c19:dd:d9:dd:c25:c25:d915:16e3/1282c19:dd:d9:dd:c25:c25:d915:16e3
2292c19:dd:d9:dd:c25:c25:d915:16e4/1282c19:dd:d9:dd:c25:c25:d915:16e4
2302c19:dd:d9:dd:c25:c25:d915:16e5/1282c19:dd:d9:dd:c25:c25:d915:16e5
2312c19:dd:d9:dd:c25:c25:d915:16e6/1282c19:dd:d9:dd:c25:c25:d915:16e6
2322c19:dd:d9:dd:c25:c25:d915:16e7/1282c19:dd:d9:dd:c25:c25:d915:16e7
2332c19:dd:d9:dd:c25:c25:d915:16e8/1282c19:dd:d9:dd:c25:c25:d915:16e8
2342c19:dd:d9:dd:c25:c25:d915:16e9/1282c19:dd:d9:dd:c25:c25:d915:16e9
2352c19:dd:d9:dd:c25:c25:d915:16ea/1282c19:dd:d9:dd:c25:c25:d915:16ea
2362c19:dd:d9:dd:c25:c25:d915:16eb/1282c19:dd:d9:dd:c25:c25:d915:16eb
2372c19:dd:d9:dd:c25:c25:d915:16ec/1282c19:dd:d9:dd:c25:c25:d915:16ec
2382c19:dd:d9:dd:c25:c25:d915:16ed/1282c19:dd:d9:dd:c25:c25:d915:16ed
2392c19:dd:d9:dd:c25:c25:d915:16ee/1282c19:dd:d9:dd:c25:c25:d915:16ee
2402c19:dd:d9:dd:c25:c25:d915:16ef/1282c19:dd:d9:dd:c25:c25:d915:16ef
2412c19:dd:d9:dd:c25:c25:d915:16f0/1282c19:dd:d9:dd:c25:c25:d915:16f0
2422c19:dd:d9:dd:c25:c25:d915:16f1/1282c19:dd:d9:dd:c25:c25:d915:16f1
2432c19:dd:d9:dd:c25:c25:d915:16f2/1282c19:dd:d9:dd:c25:c25:d915:16f2
2442c19:dd:d9:dd:c25:c25:d915:16f3/1282c19:dd:d9:dd:c25:c25:d915:16f3
2452c19:dd:d9:dd:c25:c25:d915:16f4/1282c19:dd:d9:dd:c25:c25:d915:16f4
2462c19:dd:d9:dd:c25:c25:d915:16f5/1282c19:dd:d9:dd:c25:c25:d915:16f5
2472c19:dd:d9:dd:c25:c25:d915:16f6/1282c19:dd:d9:dd:c25:c25:d915:16f6
2482c19:dd:d9:dd:c25:c25:d915:16f7/1282c19:dd:d9:dd:c25:c25:d915:16f7
2492c19:dd:d9:dd:c25:c25:d915:16f8/1282c19:dd:d9:dd:c25:c25:d915:16f8
2502c19:dd:d9:dd:c25:c25:d915:16f9/1282c19:dd:d9:dd:c25:c25:d915:16f9
2512c19:dd:d9:dd:c25:c25:d915:16fa/1282c19:dd:d9:dd:c25:c25:d915:16fa
2522c19:dd:d9:dd:c25:c25:d915:16fb/1282c19:dd:d9:dd:c25:c25:d915:16fb
2532c19:dd:d9:dd:c25:c25:d915:16fc/1282c19:dd:d9:dd:c25:c25:d915:16fc
2542c19:dd:d9:dd:c25:c25:d915:16fd/1282c19:dd:d9:dd:c25:c25:d915:16fd
2552c19:dd:d9:dd:c25:c25:d915:16fe/1282c19:dd:d9:dd:c25:c25:d915:16fe
2562c19:dd:d9:dd:c25:c25:d915:16ff/1282c19:dd:d9:dd:c25:c25:d915:16ff

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.