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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:c25:c25:dd:dd:dd:1600/119
First address
2c19:dd:c25:c25:dd:dd:dd:1600
Last address
2c19:dd:c25:c25:dd:dd:dd:17ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:1600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.1.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
7.1.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.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:c25:c25:dd:dd:dd:1600/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:1600/1272c19:dd:c25:c25:dd:dd:dd:1601
22c19:dd:c25:c25:dd:dd:dd:1602/1272c19:dd:c25:c25:dd:dd:dd:1603
32c19:dd:c25:c25:dd:dd:dd:1604/1272c19:dd:c25:c25:dd:dd:dd:1605
42c19:dd:c25:c25:dd:dd:dd:1606/1272c19:dd:c25:c25:dd:dd:dd:1607
52c19:dd:c25:c25:dd:dd:dd:1608/1272c19:dd:c25:c25:dd:dd:dd:1609
62c19:dd:c25:c25:dd:dd:dd:160a/1272c19:dd:c25:c25:dd:dd:dd:160b
72c19:dd:c25:c25:dd:dd:dd:160c/1272c19:dd:c25:c25:dd:dd:dd:160d
82c19:dd:c25:c25:dd:dd:dd:160e/1272c19:dd:c25:c25:dd:dd:dd:160f
92c19:dd:c25:c25:dd:dd:dd:1610/1272c19:dd:c25:c25:dd:dd:dd:1611
102c19:dd:c25:c25:dd:dd:dd:1612/1272c19:dd:c25:c25:dd:dd:dd:1613
112c19:dd:c25:c25:dd:dd:dd:1614/1272c19:dd:c25:c25:dd:dd:dd:1615
122c19:dd:c25:c25:dd:dd:dd:1616/1272c19:dd:c25:c25:dd:dd:dd:1617
132c19:dd:c25:c25:dd:dd:dd:1618/1272c19:dd:c25:c25:dd:dd:dd:1619
142c19:dd:c25:c25:dd:dd:dd:161a/1272c19:dd:c25:c25:dd:dd:dd:161b
152c19:dd:c25:c25:dd:dd:dd:161c/1272c19:dd:c25:c25:dd:dd:dd:161d
162c19:dd:c25:c25:dd:dd:dd:161e/1272c19:dd:c25:c25:dd:dd:dd:161f
172c19:dd:c25:c25:dd:dd:dd:1620/1272c19:dd:c25:c25:dd:dd:dd:1621
182c19:dd:c25:c25:dd:dd:dd:1622/1272c19:dd:c25:c25:dd:dd:dd:1623
192c19:dd:c25:c25:dd:dd:dd:1624/1272c19:dd:c25:c25:dd:dd:dd:1625
202c19:dd:c25:c25:dd:dd:dd:1626/1272c19:dd:c25:c25:dd:dd:dd:1627
212c19:dd:c25:c25:dd:dd:dd:1628/1272c19:dd:c25:c25:dd:dd:dd:1629
222c19:dd:c25:c25:dd:dd:dd:162a/1272c19:dd:c25:c25:dd:dd:dd:162b
232c19:dd:c25:c25:dd:dd:dd:162c/1272c19:dd:c25:c25:dd:dd:dd:162d
242c19:dd:c25:c25:dd:dd:dd:162e/1272c19:dd:c25:c25:dd:dd:dd:162f
252c19:dd:c25:c25:dd:dd:dd:1630/1272c19:dd:c25:c25:dd:dd:dd:1631
262c19:dd:c25:c25:dd:dd:dd:1632/1272c19:dd:c25:c25:dd:dd:dd:1633
272c19:dd:c25:c25:dd:dd:dd:1634/1272c19:dd:c25:c25:dd:dd:dd:1635
282c19:dd:c25:c25:dd:dd:dd:1636/1272c19:dd:c25:c25:dd:dd:dd:1637
292c19:dd:c25:c25:dd:dd:dd:1638/1272c19:dd:c25:c25:dd:dd:dd:1639
302c19:dd:c25:c25:dd:dd:dd:163a/1272c19:dd:c25:c25:dd:dd:dd:163b
312c19:dd:c25:c25:dd:dd:dd:163c/1272c19:dd:c25:c25:dd:dd:dd:163d
322c19:dd:c25:c25:dd:dd:dd:163e/1272c19:dd:c25:c25:dd:dd:dd:163f
332c19:dd:c25:c25:dd:dd:dd:1640/1272c19:dd:c25:c25:dd:dd:dd:1641
342c19:dd:c25:c25:dd:dd:dd:1642/1272c19:dd:c25:c25:dd:dd:dd:1643
352c19:dd:c25:c25:dd:dd:dd:1644/1272c19:dd:c25:c25:dd:dd:dd:1645
362c19:dd:c25:c25:dd:dd:dd:1646/1272c19:dd:c25:c25:dd:dd:dd:1647
372c19:dd:c25:c25:dd:dd:dd:1648/1272c19:dd:c25:c25:dd:dd:dd:1649
382c19:dd:c25:c25:dd:dd:dd:164a/1272c19:dd:c25:c25:dd:dd:dd:164b
392c19:dd:c25:c25:dd:dd:dd:164c/1272c19:dd:c25:c25:dd:dd:dd:164d
402c19:dd:c25:c25:dd:dd:dd:164e/1272c19:dd:c25:c25:dd:dd:dd:164f
412c19:dd:c25:c25:dd:dd:dd:1650/1272c19:dd:c25:c25:dd:dd:dd:1651
422c19:dd:c25:c25:dd:dd:dd:1652/1272c19:dd:c25:c25:dd:dd:dd:1653
432c19:dd:c25:c25:dd:dd:dd:1654/1272c19:dd:c25:c25:dd:dd:dd:1655
442c19:dd:c25:c25:dd:dd:dd:1656/1272c19:dd:c25:c25:dd:dd:dd:1657
452c19:dd:c25:c25:dd:dd:dd:1658/1272c19:dd:c25:c25:dd:dd:dd:1659
462c19:dd:c25:c25:dd:dd:dd:165a/1272c19:dd:c25:c25:dd:dd:dd:165b
472c19:dd:c25:c25:dd:dd:dd:165c/1272c19:dd:c25:c25:dd:dd:dd:165d
482c19:dd:c25:c25:dd:dd:dd:165e/1272c19:dd:c25:c25:dd:dd:dd:165f
492c19:dd:c25:c25:dd:dd:dd:1660/1272c19:dd:c25:c25:dd:dd:dd:1661
502c19:dd:c25:c25:dd:dd:dd:1662/1272c19:dd:c25:c25:dd:dd:dd:1663
512c19:dd:c25:c25:dd:dd:dd:1664/1272c19:dd:c25:c25:dd:dd:dd:1665
522c19:dd:c25:c25:dd:dd:dd:1666/1272c19:dd:c25:c25:dd:dd:dd:1667
532c19:dd:c25:c25:dd:dd:dd:1668/1272c19:dd:c25:c25:dd:dd:dd:1669
542c19:dd:c25:c25:dd:dd:dd:166a/1272c19:dd:c25:c25:dd:dd:dd:166b
552c19:dd:c25:c25:dd:dd:dd:166c/1272c19:dd:c25:c25:dd:dd:dd:166d
562c19:dd:c25:c25:dd:dd:dd:166e/1272c19:dd:c25:c25:dd:dd:dd:166f
572c19:dd:c25:c25:dd:dd:dd:1670/1272c19:dd:c25:c25:dd:dd:dd:1671
582c19:dd:c25:c25:dd:dd:dd:1672/1272c19:dd:c25:c25:dd:dd:dd:1673
592c19:dd:c25:c25:dd:dd:dd:1674/1272c19:dd:c25:c25:dd:dd:dd:1675
602c19:dd:c25:c25:dd:dd:dd:1676/1272c19:dd:c25:c25:dd:dd:dd:1677
612c19:dd:c25:c25:dd:dd:dd:1678/1272c19:dd:c25:c25:dd:dd:dd:1679
622c19:dd:c25:c25:dd:dd:dd:167a/1272c19:dd:c25:c25:dd:dd:dd:167b
632c19:dd:c25:c25:dd:dd:dd:167c/1272c19:dd:c25:c25:dd:dd:dd:167d
642c19:dd:c25:c25:dd:dd:dd:167e/1272c19:dd:c25:c25:dd:dd:dd:167f
652c19:dd:c25:c25:dd:dd:dd:1680/1272c19:dd:c25:c25:dd:dd:dd:1681
662c19:dd:c25:c25:dd:dd:dd:1682/1272c19:dd:c25:c25:dd:dd:dd:1683
672c19:dd:c25:c25:dd:dd:dd:1684/1272c19:dd:c25:c25:dd:dd:dd:1685
682c19:dd:c25:c25:dd:dd:dd:1686/1272c19:dd:c25:c25:dd:dd:dd:1687
692c19:dd:c25:c25:dd:dd:dd:1688/1272c19:dd:c25:c25:dd:dd:dd:1689
702c19:dd:c25:c25:dd:dd:dd:168a/1272c19:dd:c25:c25:dd:dd:dd:168b
712c19:dd:c25:c25:dd:dd:dd:168c/1272c19:dd:c25:c25:dd:dd:dd:168d
722c19:dd:c25:c25:dd:dd:dd:168e/1272c19:dd:c25:c25:dd:dd:dd:168f
732c19:dd:c25:c25:dd:dd:dd:1690/1272c19:dd:c25:c25:dd:dd:dd:1691
742c19:dd:c25:c25:dd:dd:dd:1692/1272c19:dd:c25:c25:dd:dd:dd:1693
752c19:dd:c25:c25:dd:dd:dd:1694/1272c19:dd:c25:c25:dd:dd:dd:1695
762c19:dd:c25:c25:dd:dd:dd:1696/1272c19:dd:c25:c25:dd:dd:dd:1697
772c19:dd:c25:c25:dd:dd:dd:1698/1272c19:dd:c25:c25:dd:dd:dd:1699
782c19:dd:c25:c25:dd:dd:dd:169a/1272c19:dd:c25:c25:dd:dd:dd:169b
792c19:dd:c25:c25:dd:dd:dd:169c/1272c19:dd:c25:c25:dd:dd:dd:169d
802c19:dd:c25:c25:dd:dd:dd:169e/1272c19:dd:c25:c25:dd:dd:dd:169f
812c19:dd:c25:c25:dd:dd:dd:16a0/1272c19:dd:c25:c25:dd:dd:dd:16a1
822c19:dd:c25:c25:dd:dd:dd:16a2/1272c19:dd:c25:c25:dd:dd:dd:16a3
832c19:dd:c25:c25:dd:dd:dd:16a4/1272c19:dd:c25:c25:dd:dd:dd:16a5
842c19:dd:c25:c25:dd:dd:dd:16a6/1272c19:dd:c25:c25:dd:dd:dd:16a7
852c19:dd:c25:c25:dd:dd:dd:16a8/1272c19:dd:c25:c25:dd:dd:dd:16a9
862c19:dd:c25:c25:dd:dd:dd:16aa/1272c19:dd:c25:c25:dd:dd:dd:16ab
872c19:dd:c25:c25:dd:dd:dd:16ac/1272c19:dd:c25:c25:dd:dd:dd:16ad
882c19:dd:c25:c25:dd:dd:dd:16ae/1272c19:dd:c25:c25:dd:dd:dd:16af
892c19:dd:c25:c25:dd:dd:dd:16b0/1272c19:dd:c25:c25:dd:dd:dd:16b1
902c19:dd:c25:c25:dd:dd:dd:16b2/1272c19:dd:c25:c25:dd:dd:dd:16b3
912c19:dd:c25:c25:dd:dd:dd:16b4/1272c19:dd:c25:c25:dd:dd:dd:16b5
922c19:dd:c25:c25:dd:dd:dd:16b6/1272c19:dd:c25:c25:dd:dd:dd:16b7
932c19:dd:c25:c25:dd:dd:dd:16b8/1272c19:dd:c25:c25:dd:dd:dd:16b9
942c19:dd:c25:c25:dd:dd:dd:16ba/1272c19:dd:c25:c25:dd:dd:dd:16bb
952c19:dd:c25:c25:dd:dd:dd:16bc/1272c19:dd:c25:c25:dd:dd:dd:16bd
962c19:dd:c25:c25:dd:dd:dd:16be/1272c19:dd:c25:c25:dd:dd:dd:16bf
972c19:dd:c25:c25:dd:dd:dd:16c0/1272c19:dd:c25:c25:dd:dd:dd:16c1
982c19:dd:c25:c25:dd:dd:dd:16c2/1272c19:dd:c25:c25:dd:dd:dd:16c3
992c19:dd:c25:c25:dd:dd:dd:16c4/1272c19:dd:c25:c25:dd:dd:dd:16c5
1002c19:dd:c25:c25:dd:dd:dd:16c6/1272c19:dd:c25:c25:dd:dd:dd:16c7
1012c19:dd:c25:c25:dd:dd:dd:16c8/1272c19:dd:c25:c25:dd:dd:dd:16c9
1022c19:dd:c25:c25:dd:dd:dd:16ca/1272c19:dd:c25:c25:dd:dd:dd:16cb
1032c19:dd:c25:c25:dd:dd:dd:16cc/1272c19:dd:c25:c25:dd:dd:dd:16cd
1042c19:dd:c25:c25:dd:dd:dd:16ce/1272c19:dd:c25:c25:dd:dd:dd:16cf
1052c19:dd:c25:c25:dd:dd:dd:16d0/1272c19:dd:c25:c25:dd:dd:dd:16d1
1062c19:dd:c25:c25:dd:dd:dd:16d2/1272c19:dd:c25:c25:dd:dd:dd:16d3
1072c19:dd:c25:c25:dd:dd:dd:16d4/1272c19:dd:c25:c25:dd:dd:dd:16d5
1082c19:dd:c25:c25:dd:dd:dd:16d6/1272c19:dd:c25:c25:dd:dd:dd:16d7
1092c19:dd:c25:c25:dd:dd:dd:16d8/1272c19:dd:c25:c25:dd:dd:dd:16d9
1102c19:dd:c25:c25:dd:dd:dd:16da/1272c19:dd:c25:c25:dd:dd:dd:16db
1112c19:dd:c25:c25:dd:dd:dd:16dc/1272c19:dd:c25:c25:dd:dd:dd:16dd
1122c19:dd:c25:c25:dd:dd:dd:16de/1272c19:dd:c25:c25:dd:dd:dd:16df
1132c19:dd:c25:c25:dd:dd:dd:16e0/1272c19:dd:c25:c25:dd:dd:dd:16e1
1142c19:dd:c25:c25:dd:dd:dd:16e2/1272c19:dd:c25:c25:dd:dd:dd:16e3
1152c19:dd:c25:c25:dd:dd:dd:16e4/1272c19:dd:c25:c25:dd:dd:dd:16e5
1162c19:dd:c25:c25:dd:dd:dd:16e6/1272c19:dd:c25:c25:dd:dd:dd:16e7
1172c19:dd:c25:c25:dd:dd:dd:16e8/1272c19:dd:c25:c25:dd:dd:dd:16e9
1182c19:dd:c25:c25:dd:dd:dd:16ea/1272c19:dd:c25:c25:dd:dd:dd:16eb
1192c19:dd:c25:c25:dd:dd:dd:16ec/1272c19:dd:c25:c25:dd:dd:dd:16ed
1202c19:dd:c25:c25:dd:dd:dd:16ee/1272c19:dd:c25:c25:dd:dd:dd:16ef
1212c19:dd:c25:c25:dd:dd:dd:16f0/1272c19:dd:c25:c25:dd:dd:dd:16f1
1222c19:dd:c25:c25:dd:dd:dd:16f2/1272c19:dd:c25:c25:dd:dd:dd:16f3
1232c19:dd:c25:c25:dd:dd:dd:16f4/1272c19:dd:c25:c25:dd:dd:dd:16f5
1242c19:dd:c25:c25:dd:dd:dd:16f6/1272c19:dd:c25:c25:dd:dd:dd:16f7
1252c19:dd:c25:c25:dd:dd:dd:16f8/1272c19:dd:c25:c25:dd:dd:dd:16f9
1262c19:dd:c25:c25:dd:dd:dd:16fa/1272c19:dd:c25:c25:dd:dd:dd:16fb
1272c19:dd:c25:c25:dd:dd:dd:16fc/1272c19:dd:c25:c25:dd:dd:dd:16fd
1282c19:dd:c25:c25:dd:dd:dd:16fe/1272c19:dd:c25:c25:dd:dd:dd:16ff
1292c19:dd:c25:c25:dd:dd:dd:1700/1272c19:dd:c25:c25:dd:dd:dd:1701
1302c19:dd:c25:c25:dd:dd:dd:1702/1272c19:dd:c25:c25:dd:dd:dd:1703
1312c19:dd:c25:c25:dd:dd:dd:1704/1272c19:dd:c25:c25:dd:dd:dd:1705
1322c19:dd:c25:c25:dd:dd:dd:1706/1272c19:dd:c25:c25:dd:dd:dd:1707
1332c19:dd:c25:c25:dd:dd:dd:1708/1272c19:dd:c25:c25:dd:dd:dd:1709
1342c19:dd:c25:c25:dd:dd:dd:170a/1272c19:dd:c25:c25:dd:dd:dd:170b
1352c19:dd:c25:c25:dd:dd:dd:170c/1272c19:dd:c25:c25:dd:dd:dd:170d
1362c19:dd:c25:c25:dd:dd:dd:170e/1272c19:dd:c25:c25:dd:dd:dd:170f
1372c19:dd:c25:c25:dd:dd:dd:1710/1272c19:dd:c25:c25:dd:dd:dd:1711
1382c19:dd:c25:c25:dd:dd:dd:1712/1272c19:dd:c25:c25:dd:dd:dd:1713
1392c19:dd:c25:c25:dd:dd:dd:1714/1272c19:dd:c25:c25:dd:dd:dd:1715
1402c19:dd:c25:c25:dd:dd:dd:1716/1272c19:dd:c25:c25:dd:dd:dd:1717
1412c19:dd:c25:c25:dd:dd:dd:1718/1272c19:dd:c25:c25:dd:dd:dd:1719
1422c19:dd:c25:c25:dd:dd:dd:171a/1272c19:dd:c25:c25:dd:dd:dd:171b
1432c19:dd:c25:c25:dd:dd:dd:171c/1272c19:dd:c25:c25:dd:dd:dd:171d
1442c19:dd:c25:c25:dd:dd:dd:171e/1272c19:dd:c25:c25:dd:dd:dd:171f
1452c19:dd:c25:c25:dd:dd:dd:1720/1272c19:dd:c25:c25:dd:dd:dd:1721
1462c19:dd:c25:c25:dd:dd:dd:1722/1272c19:dd:c25:c25:dd:dd:dd:1723
1472c19:dd:c25:c25:dd:dd:dd:1724/1272c19:dd:c25:c25:dd:dd:dd:1725
1482c19:dd:c25:c25:dd:dd:dd:1726/1272c19:dd:c25:c25:dd:dd:dd:1727
1492c19:dd:c25:c25:dd:dd:dd:1728/1272c19:dd:c25:c25:dd:dd:dd:1729
1502c19:dd:c25:c25:dd:dd:dd:172a/1272c19:dd:c25:c25:dd:dd:dd:172b
1512c19:dd:c25:c25:dd:dd:dd:172c/1272c19:dd:c25:c25:dd:dd:dd:172d
1522c19:dd:c25:c25:dd:dd:dd:172e/1272c19:dd:c25:c25:dd:dd:dd:172f
1532c19:dd:c25:c25:dd:dd:dd:1730/1272c19:dd:c25:c25:dd:dd:dd:1731
1542c19:dd:c25:c25:dd:dd:dd:1732/1272c19:dd:c25:c25:dd:dd:dd:1733
1552c19:dd:c25:c25:dd:dd:dd:1734/1272c19:dd:c25:c25:dd:dd:dd:1735
1562c19:dd:c25:c25:dd:dd:dd:1736/1272c19:dd:c25:c25:dd:dd:dd:1737
1572c19:dd:c25:c25:dd:dd:dd:1738/1272c19:dd:c25:c25:dd:dd:dd:1739
1582c19:dd:c25:c25:dd:dd:dd:173a/1272c19:dd:c25:c25:dd:dd:dd:173b
1592c19:dd:c25:c25:dd:dd:dd:173c/1272c19:dd:c25:c25:dd:dd:dd:173d
1602c19:dd:c25:c25:dd:dd:dd:173e/1272c19:dd:c25:c25:dd:dd:dd:173f
1612c19:dd:c25:c25:dd:dd:dd:1740/1272c19:dd:c25:c25:dd:dd:dd:1741
1622c19:dd:c25:c25:dd:dd:dd:1742/1272c19:dd:c25:c25:dd:dd:dd:1743
1632c19:dd:c25:c25:dd:dd:dd:1744/1272c19:dd:c25:c25:dd:dd:dd:1745
1642c19:dd:c25:c25:dd:dd:dd:1746/1272c19:dd:c25:c25:dd:dd:dd:1747
1652c19:dd:c25:c25:dd:dd:dd:1748/1272c19:dd:c25:c25:dd:dd:dd:1749
1662c19:dd:c25:c25:dd:dd:dd:174a/1272c19:dd:c25:c25:dd:dd:dd:174b
1672c19:dd:c25:c25:dd:dd:dd:174c/1272c19:dd:c25:c25:dd:dd:dd:174d
1682c19:dd:c25:c25:dd:dd:dd:174e/1272c19:dd:c25:c25:dd:dd:dd:174f
1692c19:dd:c25:c25:dd:dd:dd:1750/1272c19:dd:c25:c25:dd:dd:dd:1751
1702c19:dd:c25:c25:dd:dd:dd:1752/1272c19:dd:c25:c25:dd:dd:dd:1753
1712c19:dd:c25:c25:dd:dd:dd:1754/1272c19:dd:c25:c25:dd:dd:dd:1755
1722c19:dd:c25:c25:dd:dd:dd:1756/1272c19:dd:c25:c25:dd:dd:dd:1757
1732c19:dd:c25:c25:dd:dd:dd:1758/1272c19:dd:c25:c25:dd:dd:dd:1759
1742c19:dd:c25:c25:dd:dd:dd:175a/1272c19:dd:c25:c25:dd:dd:dd:175b
1752c19:dd:c25:c25:dd:dd:dd:175c/1272c19:dd:c25:c25:dd:dd:dd:175d
1762c19:dd:c25:c25:dd:dd:dd:175e/1272c19:dd:c25:c25:dd:dd:dd:175f
1772c19:dd:c25:c25:dd:dd:dd:1760/1272c19:dd:c25:c25:dd:dd:dd:1761
1782c19:dd:c25:c25:dd:dd:dd:1762/1272c19:dd:c25:c25:dd:dd:dd:1763
1792c19:dd:c25:c25:dd:dd:dd:1764/1272c19:dd:c25:c25:dd:dd:dd:1765
1802c19:dd:c25:c25:dd:dd:dd:1766/1272c19:dd:c25:c25:dd:dd:dd:1767
1812c19:dd:c25:c25:dd:dd:dd:1768/1272c19:dd:c25:c25:dd:dd:dd:1769
1822c19:dd:c25:c25:dd:dd:dd:176a/1272c19:dd:c25:c25:dd:dd:dd:176b
1832c19:dd:c25:c25:dd:dd:dd:176c/1272c19:dd:c25:c25:dd:dd:dd:176d
1842c19:dd:c25:c25:dd:dd:dd:176e/1272c19:dd:c25:c25:dd:dd:dd:176f
1852c19:dd:c25:c25:dd:dd:dd:1770/1272c19:dd:c25:c25:dd:dd:dd:1771
1862c19:dd:c25:c25:dd:dd:dd:1772/1272c19:dd:c25:c25:dd:dd:dd:1773
1872c19:dd:c25:c25:dd:dd:dd:1774/1272c19:dd:c25:c25:dd:dd:dd:1775
1882c19:dd:c25:c25:dd:dd:dd:1776/1272c19:dd:c25:c25:dd:dd:dd:1777
1892c19:dd:c25:c25:dd:dd:dd:1778/1272c19:dd:c25:c25:dd:dd:dd:1779
1902c19:dd:c25:c25:dd:dd:dd:177a/1272c19:dd:c25:c25:dd:dd:dd:177b
1912c19:dd:c25:c25:dd:dd:dd:177c/1272c19:dd:c25:c25:dd:dd:dd:177d
1922c19:dd:c25:c25:dd:dd:dd:177e/1272c19:dd:c25:c25:dd:dd:dd:177f
1932c19:dd:c25:c25:dd:dd:dd:1780/1272c19:dd:c25:c25:dd:dd:dd:1781
1942c19:dd:c25:c25:dd:dd:dd:1782/1272c19:dd:c25:c25:dd:dd:dd:1783
1952c19:dd:c25:c25:dd:dd:dd:1784/1272c19:dd:c25:c25:dd:dd:dd:1785
1962c19:dd:c25:c25:dd:dd:dd:1786/1272c19:dd:c25:c25:dd:dd:dd:1787
1972c19:dd:c25:c25:dd:dd:dd:1788/1272c19:dd:c25:c25:dd:dd:dd:1789
1982c19:dd:c25:c25:dd:dd:dd:178a/1272c19:dd:c25:c25:dd:dd:dd:178b
1992c19:dd:c25:c25:dd:dd:dd:178c/1272c19:dd:c25:c25:dd:dd:dd:178d
2002c19:dd:c25:c25:dd:dd:dd:178e/1272c19:dd:c25:c25:dd:dd:dd:178f
2012c19:dd:c25:c25:dd:dd:dd:1790/1272c19:dd:c25:c25:dd:dd:dd:1791
2022c19:dd:c25:c25:dd:dd:dd:1792/1272c19:dd:c25:c25:dd:dd:dd:1793
2032c19:dd:c25:c25:dd:dd:dd:1794/1272c19:dd:c25:c25:dd:dd:dd:1795
2042c19:dd:c25:c25:dd:dd:dd:1796/1272c19:dd:c25:c25:dd:dd:dd:1797
2052c19:dd:c25:c25:dd:dd:dd:1798/1272c19:dd:c25:c25:dd:dd:dd:1799
2062c19:dd:c25:c25:dd:dd:dd:179a/1272c19:dd:c25:c25:dd:dd:dd:179b
2072c19:dd:c25:c25:dd:dd:dd:179c/1272c19:dd:c25:c25:dd:dd:dd:179d
2082c19:dd:c25:c25:dd:dd:dd:179e/1272c19:dd:c25:c25:dd:dd:dd:179f
2092c19:dd:c25:c25:dd:dd:dd:17a0/1272c19:dd:c25:c25:dd:dd:dd:17a1
2102c19:dd:c25:c25:dd:dd:dd:17a2/1272c19:dd:c25:c25:dd:dd:dd:17a3
2112c19:dd:c25:c25:dd:dd:dd:17a4/1272c19:dd:c25:c25:dd:dd:dd:17a5
2122c19:dd:c25:c25:dd:dd:dd:17a6/1272c19:dd:c25:c25:dd:dd:dd:17a7
2132c19:dd:c25:c25:dd:dd:dd:17a8/1272c19:dd:c25:c25:dd:dd:dd:17a9
2142c19:dd:c25:c25:dd:dd:dd:17aa/1272c19:dd:c25:c25:dd:dd:dd:17ab
2152c19:dd:c25:c25:dd:dd:dd:17ac/1272c19:dd:c25:c25:dd:dd:dd:17ad
2162c19:dd:c25:c25:dd:dd:dd:17ae/1272c19:dd:c25:c25:dd:dd:dd:17af
2172c19:dd:c25:c25:dd:dd:dd:17b0/1272c19:dd:c25:c25:dd:dd:dd:17b1
2182c19:dd:c25:c25:dd:dd:dd:17b2/1272c19:dd:c25:c25:dd:dd:dd:17b3
2192c19:dd:c25:c25:dd:dd:dd:17b4/1272c19:dd:c25:c25:dd:dd:dd:17b5
2202c19:dd:c25:c25:dd:dd:dd:17b6/1272c19:dd:c25:c25:dd:dd:dd:17b7
2212c19:dd:c25:c25:dd:dd:dd:17b8/1272c19:dd:c25:c25:dd:dd:dd:17b9
2222c19:dd:c25:c25:dd:dd:dd:17ba/1272c19:dd:c25:c25:dd:dd:dd:17bb
2232c19:dd:c25:c25:dd:dd:dd:17bc/1272c19:dd:c25:c25:dd:dd:dd:17bd
2242c19:dd:c25:c25:dd:dd:dd:17be/1272c19:dd:c25:c25:dd:dd:dd:17bf
2252c19:dd:c25:c25:dd:dd:dd:17c0/1272c19:dd:c25:c25:dd:dd:dd:17c1
2262c19:dd:c25:c25:dd:dd:dd:17c2/1272c19:dd:c25:c25:dd:dd:dd:17c3
2272c19:dd:c25:c25:dd:dd:dd:17c4/1272c19:dd:c25:c25:dd:dd:dd:17c5
2282c19:dd:c25:c25:dd:dd:dd:17c6/1272c19:dd:c25:c25:dd:dd:dd:17c7
2292c19:dd:c25:c25:dd:dd:dd:17c8/1272c19:dd:c25:c25:dd:dd:dd:17c9
2302c19:dd:c25:c25:dd:dd:dd:17ca/1272c19:dd:c25:c25:dd:dd:dd:17cb
2312c19:dd:c25:c25:dd:dd:dd:17cc/1272c19:dd:c25:c25:dd:dd:dd:17cd
2322c19:dd:c25:c25:dd:dd:dd:17ce/1272c19:dd:c25:c25:dd:dd:dd:17cf
2332c19:dd:c25:c25:dd:dd:dd:17d0/1272c19:dd:c25:c25:dd:dd:dd:17d1
2342c19:dd:c25:c25:dd:dd:dd:17d2/1272c19:dd:c25:c25:dd:dd:dd:17d3
2352c19:dd:c25:c25:dd:dd:dd:17d4/1272c19:dd:c25:c25:dd:dd:dd:17d5
2362c19:dd:c25:c25:dd:dd:dd:17d6/1272c19:dd:c25:c25:dd:dd:dd:17d7
2372c19:dd:c25:c25:dd:dd:dd:17d8/1272c19:dd:c25:c25:dd:dd:dd:17d9
2382c19:dd:c25:c25:dd:dd:dd:17da/1272c19:dd:c25:c25:dd:dd:dd:17db
2392c19:dd:c25:c25:dd:dd:dd:17dc/1272c19:dd:c25:c25:dd:dd:dd:17dd
2402c19:dd:c25:c25:dd:dd:dd:17de/1272c19:dd:c25:c25:dd:dd:dd:17df
2412c19:dd:c25:c25:dd:dd:dd:17e0/1272c19:dd:c25:c25:dd:dd:dd:17e1
2422c19:dd:c25:c25:dd:dd:dd:17e2/1272c19:dd:c25:c25:dd:dd:dd:17e3
2432c19:dd:c25:c25:dd:dd:dd:17e4/1272c19:dd:c25:c25:dd:dd:dd:17e5
2442c19:dd:c25:c25:dd:dd:dd:17e6/1272c19:dd:c25:c25:dd:dd:dd:17e7
2452c19:dd:c25:c25:dd:dd:dd:17e8/1272c19:dd:c25:c25:dd:dd:dd:17e9
2462c19:dd:c25:c25:dd:dd:dd:17ea/1272c19:dd:c25:c25:dd:dd:dd:17eb
2472c19:dd:c25:c25:dd:dd:dd:17ec/1272c19:dd:c25:c25:dd:dd:dd:17ed
2482c19:dd:c25:c25:dd:dd:dd:17ee/1272c19:dd:c25:c25:dd:dd:dd:17ef
2492c19:dd:c25:c25:dd:dd:dd:17f0/1272c19:dd:c25:c25:dd:dd:dd:17f1
2502c19:dd:c25:c25:dd:dd:dd:17f2/1272c19:dd:c25:c25:dd:dd:dd:17f3
2512c19:dd:c25:c25:dd:dd:dd:17f4/1272c19:dd:c25:c25:dd:dd:dd:17f5
2522c19:dd:c25:c25:dd:dd:dd:17f6/1272c19:dd:c25:c25:dd:dd:dd:17f7
2532c19:dd:c25:c25:dd:dd:dd:17f8/1272c19:dd:c25:c25:dd:dd:dd:17f9
2542c19:dd:c25:c25:dd:dd:dd:17fa/1272c19:dd:c25:c25:dd:dd:dd:17fb
2552c19:dd:c25:c25:dd:dd:dd:17fc/1272c19:dd:c25:c25:dd:dd:dd:17fd
2562c19:dd:c25:c25:dd:dd:dd:17fe/1272c19:dd:c25:c25:dd:dd:dd:17ff

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.