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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:1800/119
First address
2c19:dd:d9:dd:c25:c25:94de:1800
Last address
2c19:dd:d9:dd:c25:c25:94de:19ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:1800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.1.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
9.1.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/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:1800/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:1800/1282c19:dd:d9:dd:c25:c25:94de:1800
22c19:dd:d9:dd:c25:c25:94de:1801/1282c19:dd:d9:dd:c25:c25:94de:1801
32c19:dd:d9:dd:c25:c25:94de:1802/1282c19:dd:d9:dd:c25:c25:94de:1802
42c19:dd:d9:dd:c25:c25:94de:1803/1282c19:dd:d9:dd:c25:c25:94de:1803
52c19:dd:d9:dd:c25:c25:94de:1804/1282c19:dd:d9:dd:c25:c25:94de:1804
62c19:dd:d9:dd:c25:c25:94de:1805/1282c19:dd:d9:dd:c25:c25:94de:1805
72c19:dd:d9:dd:c25:c25:94de:1806/1282c19:dd:d9:dd:c25:c25:94de:1806
82c19:dd:d9:dd:c25:c25:94de:1807/1282c19:dd:d9:dd:c25:c25:94de:1807
92c19:dd:d9:dd:c25:c25:94de:1808/1282c19:dd:d9:dd:c25:c25:94de:1808
102c19:dd:d9:dd:c25:c25:94de:1809/1282c19:dd:d9:dd:c25:c25:94de:1809
112c19:dd:d9:dd:c25:c25:94de:180a/1282c19:dd:d9:dd:c25:c25:94de:180a
122c19:dd:d9:dd:c25:c25:94de:180b/1282c19:dd:d9:dd:c25:c25:94de:180b
132c19:dd:d9:dd:c25:c25:94de:180c/1282c19:dd:d9:dd:c25:c25:94de:180c
142c19:dd:d9:dd:c25:c25:94de:180d/1282c19:dd:d9:dd:c25:c25:94de:180d
152c19:dd:d9:dd:c25:c25:94de:180e/1282c19:dd:d9:dd:c25:c25:94de:180e
162c19:dd:d9:dd:c25:c25:94de:180f/1282c19:dd:d9:dd:c25:c25:94de:180f
172c19:dd:d9:dd:c25:c25:94de:1810/1282c19:dd:d9:dd:c25:c25:94de:1810
182c19:dd:d9:dd:c25:c25:94de:1811/1282c19:dd:d9:dd:c25:c25:94de:1811
192c19:dd:d9:dd:c25:c25:94de:1812/1282c19:dd:d9:dd:c25:c25:94de:1812
202c19:dd:d9:dd:c25:c25:94de:1813/1282c19:dd:d9:dd:c25:c25:94de:1813
212c19:dd:d9:dd:c25:c25:94de:1814/1282c19:dd:d9:dd:c25:c25:94de:1814
222c19:dd:d9:dd:c25:c25:94de:1815/1282c19:dd:d9:dd:c25:c25:94de:1815
232c19:dd:d9:dd:c25:c25:94de:1816/1282c19:dd:d9:dd:c25:c25:94de:1816
242c19:dd:d9:dd:c25:c25:94de:1817/1282c19:dd:d9:dd:c25:c25:94de:1817
252c19:dd:d9:dd:c25:c25:94de:1818/1282c19:dd:d9:dd:c25:c25:94de:1818
262c19:dd:d9:dd:c25:c25:94de:1819/1282c19:dd:d9:dd:c25:c25:94de:1819
272c19:dd:d9:dd:c25:c25:94de:181a/1282c19:dd:d9:dd:c25:c25:94de:181a
282c19:dd:d9:dd:c25:c25:94de:181b/1282c19:dd:d9:dd:c25:c25:94de:181b
292c19:dd:d9:dd:c25:c25:94de:181c/1282c19:dd:d9:dd:c25:c25:94de:181c
302c19:dd:d9:dd:c25:c25:94de:181d/1282c19:dd:d9:dd:c25:c25:94de:181d
312c19:dd:d9:dd:c25:c25:94de:181e/1282c19:dd:d9:dd:c25:c25:94de:181e
322c19:dd:d9:dd:c25:c25:94de:181f/1282c19:dd:d9:dd:c25:c25:94de:181f
332c19:dd:d9:dd:c25:c25:94de:1820/1282c19:dd:d9:dd:c25:c25:94de:1820
342c19:dd:d9:dd:c25:c25:94de:1821/1282c19:dd:d9:dd:c25:c25:94de:1821
352c19:dd:d9:dd:c25:c25:94de:1822/1282c19:dd:d9:dd:c25:c25:94de:1822
362c19:dd:d9:dd:c25:c25:94de:1823/1282c19:dd:d9:dd:c25:c25:94de:1823
372c19:dd:d9:dd:c25:c25:94de:1824/1282c19:dd:d9:dd:c25:c25:94de:1824
382c19:dd:d9:dd:c25:c25:94de:1825/1282c19:dd:d9:dd:c25:c25:94de:1825
392c19:dd:d9:dd:c25:c25:94de:1826/1282c19:dd:d9:dd:c25:c25:94de:1826
402c19:dd:d9:dd:c25:c25:94de:1827/1282c19:dd:d9:dd:c25:c25:94de:1827
412c19:dd:d9:dd:c25:c25:94de:1828/1282c19:dd:d9:dd:c25:c25:94de:1828
422c19:dd:d9:dd:c25:c25:94de:1829/1282c19:dd:d9:dd:c25:c25:94de:1829
432c19:dd:d9:dd:c25:c25:94de:182a/1282c19:dd:d9:dd:c25:c25:94de:182a
442c19:dd:d9:dd:c25:c25:94de:182b/1282c19:dd:d9:dd:c25:c25:94de:182b
452c19:dd:d9:dd:c25:c25:94de:182c/1282c19:dd:d9:dd:c25:c25:94de:182c
462c19:dd:d9:dd:c25:c25:94de:182d/1282c19:dd:d9:dd:c25:c25:94de:182d
472c19:dd:d9:dd:c25:c25:94de:182e/1282c19:dd:d9:dd:c25:c25:94de:182e
482c19:dd:d9:dd:c25:c25:94de:182f/1282c19:dd:d9:dd:c25:c25:94de:182f
492c19:dd:d9:dd:c25:c25:94de:1830/1282c19:dd:d9:dd:c25:c25:94de:1830
502c19:dd:d9:dd:c25:c25:94de:1831/1282c19:dd:d9:dd:c25:c25:94de:1831
512c19:dd:d9:dd:c25:c25:94de:1832/1282c19:dd:d9:dd:c25:c25:94de:1832
522c19:dd:d9:dd:c25:c25:94de:1833/1282c19:dd:d9:dd:c25:c25:94de:1833
532c19:dd:d9:dd:c25:c25:94de:1834/1282c19:dd:d9:dd:c25:c25:94de:1834
542c19:dd:d9:dd:c25:c25:94de:1835/1282c19:dd:d9:dd:c25:c25:94de:1835
552c19:dd:d9:dd:c25:c25:94de:1836/1282c19:dd:d9:dd:c25:c25:94de:1836
562c19:dd:d9:dd:c25:c25:94de:1837/1282c19:dd:d9:dd:c25:c25:94de:1837
572c19:dd:d9:dd:c25:c25:94de:1838/1282c19:dd:d9:dd:c25:c25:94de:1838
582c19:dd:d9:dd:c25:c25:94de:1839/1282c19:dd:d9:dd:c25:c25:94de:1839
592c19:dd:d9:dd:c25:c25:94de:183a/1282c19:dd:d9:dd:c25:c25:94de:183a
602c19:dd:d9:dd:c25:c25:94de:183b/1282c19:dd:d9:dd:c25:c25:94de:183b
612c19:dd:d9:dd:c25:c25:94de:183c/1282c19:dd:d9:dd:c25:c25:94de:183c
622c19:dd:d9:dd:c25:c25:94de:183d/1282c19:dd:d9:dd:c25:c25:94de:183d
632c19:dd:d9:dd:c25:c25:94de:183e/1282c19:dd:d9:dd:c25:c25:94de:183e
642c19:dd:d9:dd:c25:c25:94de:183f/1282c19:dd:d9:dd:c25:c25:94de:183f
652c19:dd:d9:dd:c25:c25:94de:1840/1282c19:dd:d9:dd:c25:c25:94de:1840
662c19:dd:d9:dd:c25:c25:94de:1841/1282c19:dd:d9:dd:c25:c25:94de:1841
672c19:dd:d9:dd:c25:c25:94de:1842/1282c19:dd:d9:dd:c25:c25:94de:1842
682c19:dd:d9:dd:c25:c25:94de:1843/1282c19:dd:d9:dd:c25:c25:94de:1843
692c19:dd:d9:dd:c25:c25:94de:1844/1282c19:dd:d9:dd:c25:c25:94de:1844
702c19:dd:d9:dd:c25:c25:94de:1845/1282c19:dd:d9:dd:c25:c25:94de:1845
712c19:dd:d9:dd:c25:c25:94de:1846/1282c19:dd:d9:dd:c25:c25:94de:1846
722c19:dd:d9:dd:c25:c25:94de:1847/1282c19:dd:d9:dd:c25:c25:94de:1847
732c19:dd:d9:dd:c25:c25:94de:1848/1282c19:dd:d9:dd:c25:c25:94de:1848
742c19:dd:d9:dd:c25:c25:94de:1849/1282c19:dd:d9:dd:c25:c25:94de:1849
752c19:dd:d9:dd:c25:c25:94de:184a/1282c19:dd:d9:dd:c25:c25:94de:184a
762c19:dd:d9:dd:c25:c25:94de:184b/1282c19:dd:d9:dd:c25:c25:94de:184b
772c19:dd:d9:dd:c25:c25:94de:184c/1282c19:dd:d9:dd:c25:c25:94de:184c
782c19:dd:d9:dd:c25:c25:94de:184d/1282c19:dd:d9:dd:c25:c25:94de:184d
792c19:dd:d9:dd:c25:c25:94de:184e/1282c19:dd:d9:dd:c25:c25:94de:184e
802c19:dd:d9:dd:c25:c25:94de:184f/1282c19:dd:d9:dd:c25:c25:94de:184f
812c19:dd:d9:dd:c25:c25:94de:1850/1282c19:dd:d9:dd:c25:c25:94de:1850
822c19:dd:d9:dd:c25:c25:94de:1851/1282c19:dd:d9:dd:c25:c25:94de:1851
832c19:dd:d9:dd:c25:c25:94de:1852/1282c19:dd:d9:dd:c25:c25:94de:1852
842c19:dd:d9:dd:c25:c25:94de:1853/1282c19:dd:d9:dd:c25:c25:94de:1853
852c19:dd:d9:dd:c25:c25:94de:1854/1282c19:dd:d9:dd:c25:c25:94de:1854
862c19:dd:d9:dd:c25:c25:94de:1855/1282c19:dd:d9:dd:c25:c25:94de:1855
872c19:dd:d9:dd:c25:c25:94de:1856/1282c19:dd:d9:dd:c25:c25:94de:1856
882c19:dd:d9:dd:c25:c25:94de:1857/1282c19:dd:d9:dd:c25:c25:94de:1857
892c19:dd:d9:dd:c25:c25:94de:1858/1282c19:dd:d9:dd:c25:c25:94de:1858
902c19:dd:d9:dd:c25:c25:94de:1859/1282c19:dd:d9:dd:c25:c25:94de:1859
912c19:dd:d9:dd:c25:c25:94de:185a/1282c19:dd:d9:dd:c25:c25:94de:185a
922c19:dd:d9:dd:c25:c25:94de:185b/1282c19:dd:d9:dd:c25:c25:94de:185b
932c19:dd:d9:dd:c25:c25:94de:185c/1282c19:dd:d9:dd:c25:c25:94de:185c
942c19:dd:d9:dd:c25:c25:94de:185d/1282c19:dd:d9:dd:c25:c25:94de:185d
952c19:dd:d9:dd:c25:c25:94de:185e/1282c19:dd:d9:dd:c25:c25:94de:185e
962c19:dd:d9:dd:c25:c25:94de:185f/1282c19:dd:d9:dd:c25:c25:94de:185f
972c19:dd:d9:dd:c25:c25:94de:1860/1282c19:dd:d9:dd:c25:c25:94de:1860
982c19:dd:d9:dd:c25:c25:94de:1861/1282c19:dd:d9:dd:c25:c25:94de:1861
992c19:dd:d9:dd:c25:c25:94de:1862/1282c19:dd:d9:dd:c25:c25:94de:1862
1002c19:dd:d9:dd:c25:c25:94de:1863/1282c19:dd:d9:dd:c25:c25:94de:1863
1012c19:dd:d9:dd:c25:c25:94de:1864/1282c19:dd:d9:dd:c25:c25:94de:1864
1022c19:dd:d9:dd:c25:c25:94de:1865/1282c19:dd:d9:dd:c25:c25:94de:1865
1032c19:dd:d9:dd:c25:c25:94de:1866/1282c19:dd:d9:dd:c25:c25:94de:1866
1042c19:dd:d9:dd:c25:c25:94de:1867/1282c19:dd:d9:dd:c25:c25:94de:1867
1052c19:dd:d9:dd:c25:c25:94de:1868/1282c19:dd:d9:dd:c25:c25:94de:1868
1062c19:dd:d9:dd:c25:c25:94de:1869/1282c19:dd:d9:dd:c25:c25:94de:1869
1072c19:dd:d9:dd:c25:c25:94de:186a/1282c19:dd:d9:dd:c25:c25:94de:186a
1082c19:dd:d9:dd:c25:c25:94de:186b/1282c19:dd:d9:dd:c25:c25:94de:186b
1092c19:dd:d9:dd:c25:c25:94de:186c/1282c19:dd:d9:dd:c25:c25:94de:186c
1102c19:dd:d9:dd:c25:c25:94de:186d/1282c19:dd:d9:dd:c25:c25:94de:186d
1112c19:dd:d9:dd:c25:c25:94de:186e/1282c19:dd:d9:dd:c25:c25:94de:186e
1122c19:dd:d9:dd:c25:c25:94de:186f/1282c19:dd:d9:dd:c25:c25:94de:186f
1132c19:dd:d9:dd:c25:c25:94de:1870/1282c19:dd:d9:dd:c25:c25:94de:1870
1142c19:dd:d9:dd:c25:c25:94de:1871/1282c19:dd:d9:dd:c25:c25:94de:1871
1152c19:dd:d9:dd:c25:c25:94de:1872/1282c19:dd:d9:dd:c25:c25:94de:1872
1162c19:dd:d9:dd:c25:c25:94de:1873/1282c19:dd:d9:dd:c25:c25:94de:1873
1172c19:dd:d9:dd:c25:c25:94de:1874/1282c19:dd:d9:dd:c25:c25:94de:1874
1182c19:dd:d9:dd:c25:c25:94de:1875/1282c19:dd:d9:dd:c25:c25:94de:1875
1192c19:dd:d9:dd:c25:c25:94de:1876/1282c19:dd:d9:dd:c25:c25:94de:1876
1202c19:dd:d9:dd:c25:c25:94de:1877/1282c19:dd:d9:dd:c25:c25:94de:1877
1212c19:dd:d9:dd:c25:c25:94de:1878/1282c19:dd:d9:dd:c25:c25:94de:1878
1222c19:dd:d9:dd:c25:c25:94de:1879/1282c19:dd:d9:dd:c25:c25:94de:1879
1232c19:dd:d9:dd:c25:c25:94de:187a/1282c19:dd:d9:dd:c25:c25:94de:187a
1242c19:dd:d9:dd:c25:c25:94de:187b/1282c19:dd:d9:dd:c25:c25:94de:187b
1252c19:dd:d9:dd:c25:c25:94de:187c/1282c19:dd:d9:dd:c25:c25:94de:187c
1262c19:dd:d9:dd:c25:c25:94de:187d/1282c19:dd:d9:dd:c25:c25:94de:187d
1272c19:dd:d9:dd:c25:c25:94de:187e/1282c19:dd:d9:dd:c25:c25:94de:187e
1282c19:dd:d9:dd:c25:c25:94de:187f/1282c19:dd:d9:dd:c25:c25:94de:187f
1292c19:dd:d9:dd:c25:c25:94de:1880/1282c19:dd:d9:dd:c25:c25:94de:1880
1302c19:dd:d9:dd:c25:c25:94de:1881/1282c19:dd:d9:dd:c25:c25:94de:1881
1312c19:dd:d9:dd:c25:c25:94de:1882/1282c19:dd:d9:dd:c25:c25:94de:1882
1322c19:dd:d9:dd:c25:c25:94de:1883/1282c19:dd:d9:dd:c25:c25:94de:1883
1332c19:dd:d9:dd:c25:c25:94de:1884/1282c19:dd:d9:dd:c25:c25:94de:1884
1342c19:dd:d9:dd:c25:c25:94de:1885/1282c19:dd:d9:dd:c25:c25:94de:1885
1352c19:dd:d9:dd:c25:c25:94de:1886/1282c19:dd:d9:dd:c25:c25:94de:1886
1362c19:dd:d9:dd:c25:c25:94de:1887/1282c19:dd:d9:dd:c25:c25:94de:1887
1372c19:dd:d9:dd:c25:c25:94de:1888/1282c19:dd:d9:dd:c25:c25:94de:1888
1382c19:dd:d9:dd:c25:c25:94de:1889/1282c19:dd:d9:dd:c25:c25:94de:1889
1392c19:dd:d9:dd:c25:c25:94de:188a/1282c19:dd:d9:dd:c25:c25:94de:188a
1402c19:dd:d9:dd:c25:c25:94de:188b/1282c19:dd:d9:dd:c25:c25:94de:188b
1412c19:dd:d9:dd:c25:c25:94de:188c/1282c19:dd:d9:dd:c25:c25:94de:188c
1422c19:dd:d9:dd:c25:c25:94de:188d/1282c19:dd:d9:dd:c25:c25:94de:188d
1432c19:dd:d9:dd:c25:c25:94de:188e/1282c19:dd:d9:dd:c25:c25:94de:188e
1442c19:dd:d9:dd:c25:c25:94de:188f/1282c19:dd:d9:dd:c25:c25:94de:188f
1452c19:dd:d9:dd:c25:c25:94de:1890/1282c19:dd:d9:dd:c25:c25:94de:1890
1462c19:dd:d9:dd:c25:c25:94de:1891/1282c19:dd:d9:dd:c25:c25:94de:1891
1472c19:dd:d9:dd:c25:c25:94de:1892/1282c19:dd:d9:dd:c25:c25:94de:1892
1482c19:dd:d9:dd:c25:c25:94de:1893/1282c19:dd:d9:dd:c25:c25:94de:1893
1492c19:dd:d9:dd:c25:c25:94de:1894/1282c19:dd:d9:dd:c25:c25:94de:1894
1502c19:dd:d9:dd:c25:c25:94de:1895/1282c19:dd:d9:dd:c25:c25:94de:1895
1512c19:dd:d9:dd:c25:c25:94de:1896/1282c19:dd:d9:dd:c25:c25:94de:1896
1522c19:dd:d9:dd:c25:c25:94de:1897/1282c19:dd:d9:dd:c25:c25:94de:1897
1532c19:dd:d9:dd:c25:c25:94de:1898/1282c19:dd:d9:dd:c25:c25:94de:1898
1542c19:dd:d9:dd:c25:c25:94de:1899/1282c19:dd:d9:dd:c25:c25:94de:1899
1552c19:dd:d9:dd:c25:c25:94de:189a/1282c19:dd:d9:dd:c25:c25:94de:189a
1562c19:dd:d9:dd:c25:c25:94de:189b/1282c19:dd:d9:dd:c25:c25:94de:189b
1572c19:dd:d9:dd:c25:c25:94de:189c/1282c19:dd:d9:dd:c25:c25:94de:189c
1582c19:dd:d9:dd:c25:c25:94de:189d/1282c19:dd:d9:dd:c25:c25:94de:189d
1592c19:dd:d9:dd:c25:c25:94de:189e/1282c19:dd:d9:dd:c25:c25:94de:189e
1602c19:dd:d9:dd:c25:c25:94de:189f/1282c19:dd:d9:dd:c25:c25:94de:189f
1612c19:dd:d9:dd:c25:c25:94de:18a0/1282c19:dd:d9:dd:c25:c25:94de:18a0
1622c19:dd:d9:dd:c25:c25:94de:18a1/1282c19:dd:d9:dd:c25:c25:94de:18a1
1632c19:dd:d9:dd:c25:c25:94de:18a2/1282c19:dd:d9:dd:c25:c25:94de:18a2
1642c19:dd:d9:dd:c25:c25:94de:18a3/1282c19:dd:d9:dd:c25:c25:94de:18a3
1652c19:dd:d9:dd:c25:c25:94de:18a4/1282c19:dd:d9:dd:c25:c25:94de:18a4
1662c19:dd:d9:dd:c25:c25:94de:18a5/1282c19:dd:d9:dd:c25:c25:94de:18a5
1672c19:dd:d9:dd:c25:c25:94de:18a6/1282c19:dd:d9:dd:c25:c25:94de:18a6
1682c19:dd:d9:dd:c25:c25:94de:18a7/1282c19:dd:d9:dd:c25:c25:94de:18a7
1692c19:dd:d9:dd:c25:c25:94de:18a8/1282c19:dd:d9:dd:c25:c25:94de:18a8
1702c19:dd:d9:dd:c25:c25:94de:18a9/1282c19:dd:d9:dd:c25:c25:94de:18a9
1712c19:dd:d9:dd:c25:c25:94de:18aa/1282c19:dd:d9:dd:c25:c25:94de:18aa
1722c19:dd:d9:dd:c25:c25:94de:18ab/1282c19:dd:d9:dd:c25:c25:94de:18ab
1732c19:dd:d9:dd:c25:c25:94de:18ac/1282c19:dd:d9:dd:c25:c25:94de:18ac
1742c19:dd:d9:dd:c25:c25:94de:18ad/1282c19:dd:d9:dd:c25:c25:94de:18ad
1752c19:dd:d9:dd:c25:c25:94de:18ae/1282c19:dd:d9:dd:c25:c25:94de:18ae
1762c19:dd:d9:dd:c25:c25:94de:18af/1282c19:dd:d9:dd:c25:c25:94de:18af
1772c19:dd:d9:dd:c25:c25:94de:18b0/1282c19:dd:d9:dd:c25:c25:94de:18b0
1782c19:dd:d9:dd:c25:c25:94de:18b1/1282c19:dd:d9:dd:c25:c25:94de:18b1
1792c19:dd:d9:dd:c25:c25:94de:18b2/1282c19:dd:d9:dd:c25:c25:94de:18b2
1802c19:dd:d9:dd:c25:c25:94de:18b3/1282c19:dd:d9:dd:c25:c25:94de:18b3
1812c19:dd:d9:dd:c25:c25:94de:18b4/1282c19:dd:d9:dd:c25:c25:94de:18b4
1822c19:dd:d9:dd:c25:c25:94de:18b5/1282c19:dd:d9:dd:c25:c25:94de:18b5
1832c19:dd:d9:dd:c25:c25:94de:18b6/1282c19:dd:d9:dd:c25:c25:94de:18b6
1842c19:dd:d9:dd:c25:c25:94de:18b7/1282c19:dd:d9:dd:c25:c25:94de:18b7
1852c19:dd:d9:dd:c25:c25:94de:18b8/1282c19:dd:d9:dd:c25:c25:94de:18b8
1862c19:dd:d9:dd:c25:c25:94de:18b9/1282c19:dd:d9:dd:c25:c25:94de:18b9
1872c19:dd:d9:dd:c25:c25:94de:18ba/1282c19:dd:d9:dd:c25:c25:94de:18ba
1882c19:dd:d9:dd:c25:c25:94de:18bb/1282c19:dd:d9:dd:c25:c25:94de:18bb
1892c19:dd:d9:dd:c25:c25:94de:18bc/1282c19:dd:d9:dd:c25:c25:94de:18bc
1902c19:dd:d9:dd:c25:c25:94de:18bd/1282c19:dd:d9:dd:c25:c25:94de:18bd
1912c19:dd:d9:dd:c25:c25:94de:18be/1282c19:dd:d9:dd:c25:c25:94de:18be
1922c19:dd:d9:dd:c25:c25:94de:18bf/1282c19:dd:d9:dd:c25:c25:94de:18bf
1932c19:dd:d9:dd:c25:c25:94de:18c0/1282c19:dd:d9:dd:c25:c25:94de:18c0
1942c19:dd:d9:dd:c25:c25:94de:18c1/1282c19:dd:d9:dd:c25:c25:94de:18c1
1952c19:dd:d9:dd:c25:c25:94de:18c2/1282c19:dd:d9:dd:c25:c25:94de:18c2
1962c19:dd:d9:dd:c25:c25:94de:18c3/1282c19:dd:d9:dd:c25:c25:94de:18c3
1972c19:dd:d9:dd:c25:c25:94de:18c4/1282c19:dd:d9:dd:c25:c25:94de:18c4
1982c19:dd:d9:dd:c25:c25:94de:18c5/1282c19:dd:d9:dd:c25:c25:94de:18c5
1992c19:dd:d9:dd:c25:c25:94de:18c6/1282c19:dd:d9:dd:c25:c25:94de:18c6
2002c19:dd:d9:dd:c25:c25:94de:18c7/1282c19:dd:d9:dd:c25:c25:94de:18c7
2012c19:dd:d9:dd:c25:c25:94de:18c8/1282c19:dd:d9:dd:c25:c25:94de:18c8
2022c19:dd:d9:dd:c25:c25:94de:18c9/1282c19:dd:d9:dd:c25:c25:94de:18c9
2032c19:dd:d9:dd:c25:c25:94de:18ca/1282c19:dd:d9:dd:c25:c25:94de:18ca
2042c19:dd:d9:dd:c25:c25:94de:18cb/1282c19:dd:d9:dd:c25:c25:94de:18cb
2052c19:dd:d9:dd:c25:c25:94de:18cc/1282c19:dd:d9:dd:c25:c25:94de:18cc
2062c19:dd:d9:dd:c25:c25:94de:18cd/1282c19:dd:d9:dd:c25:c25:94de:18cd
2072c19:dd:d9:dd:c25:c25:94de:18ce/1282c19:dd:d9:dd:c25:c25:94de:18ce
2082c19:dd:d9:dd:c25:c25:94de:18cf/1282c19:dd:d9:dd:c25:c25:94de:18cf
2092c19:dd:d9:dd:c25:c25:94de:18d0/1282c19:dd:d9:dd:c25:c25:94de:18d0
2102c19:dd:d9:dd:c25:c25:94de:18d1/1282c19:dd:d9:dd:c25:c25:94de:18d1
2112c19:dd:d9:dd:c25:c25:94de:18d2/1282c19:dd:d9:dd:c25:c25:94de:18d2
2122c19:dd:d9:dd:c25:c25:94de:18d3/1282c19:dd:d9:dd:c25:c25:94de:18d3
2132c19:dd:d9:dd:c25:c25:94de:18d4/1282c19:dd:d9:dd:c25:c25:94de:18d4
2142c19:dd:d9:dd:c25:c25:94de:18d5/1282c19:dd:d9:dd:c25:c25:94de:18d5
2152c19:dd:d9:dd:c25:c25:94de:18d6/1282c19:dd:d9:dd:c25:c25:94de:18d6
2162c19:dd:d9:dd:c25:c25:94de:18d7/1282c19:dd:d9:dd:c25:c25:94de:18d7
2172c19:dd:d9:dd:c25:c25:94de:18d8/1282c19:dd:d9:dd:c25:c25:94de:18d8
2182c19:dd:d9:dd:c25:c25:94de:18d9/1282c19:dd:d9:dd:c25:c25:94de:18d9
2192c19:dd:d9:dd:c25:c25:94de:18da/1282c19:dd:d9:dd:c25:c25:94de:18da
2202c19:dd:d9:dd:c25:c25:94de:18db/1282c19:dd:d9:dd:c25:c25:94de:18db
2212c19:dd:d9:dd:c25:c25:94de:18dc/1282c19:dd:d9:dd:c25:c25:94de:18dc
2222c19:dd:d9:dd:c25:c25:94de:18dd/1282c19:dd:d9:dd:c25:c25:94de:18dd
2232c19:dd:d9:dd:c25:c25:94de:18de/1282c19:dd:d9:dd:c25:c25:94de:18de
2242c19:dd:d9:dd:c25:c25:94de:18df/1282c19:dd:d9:dd:c25:c25:94de:18df
2252c19:dd:d9:dd:c25:c25:94de:18e0/1282c19:dd:d9:dd:c25:c25:94de:18e0
2262c19:dd:d9:dd:c25:c25:94de:18e1/1282c19:dd:d9:dd:c25:c25:94de:18e1
2272c19:dd:d9:dd:c25:c25:94de:18e2/1282c19:dd:d9:dd:c25:c25:94de:18e2
2282c19:dd:d9:dd:c25:c25:94de:18e3/1282c19:dd:d9:dd:c25:c25:94de:18e3
2292c19:dd:d9:dd:c25:c25:94de:18e4/1282c19:dd:d9:dd:c25:c25:94de:18e4
2302c19:dd:d9:dd:c25:c25:94de:18e5/1282c19:dd:d9:dd:c25:c25:94de:18e5
2312c19:dd:d9:dd:c25:c25:94de:18e6/1282c19:dd:d9:dd:c25:c25:94de:18e6
2322c19:dd:d9:dd:c25:c25:94de:18e7/1282c19:dd:d9:dd:c25:c25:94de:18e7
2332c19:dd:d9:dd:c25:c25:94de:18e8/1282c19:dd:d9:dd:c25:c25:94de:18e8
2342c19:dd:d9:dd:c25:c25:94de:18e9/1282c19:dd:d9:dd:c25:c25:94de:18e9
2352c19:dd:d9:dd:c25:c25:94de:18ea/1282c19:dd:d9:dd:c25:c25:94de:18ea
2362c19:dd:d9:dd:c25:c25:94de:18eb/1282c19:dd:d9:dd:c25:c25:94de:18eb
2372c19:dd:d9:dd:c25:c25:94de:18ec/1282c19:dd:d9:dd:c25:c25:94de:18ec
2382c19:dd:d9:dd:c25:c25:94de:18ed/1282c19:dd:d9:dd:c25:c25:94de:18ed
2392c19:dd:d9:dd:c25:c25:94de:18ee/1282c19:dd:d9:dd:c25:c25:94de:18ee
2402c19:dd:d9:dd:c25:c25:94de:18ef/1282c19:dd:d9:dd:c25:c25:94de:18ef
2412c19:dd:d9:dd:c25:c25:94de:18f0/1282c19:dd:d9:dd:c25:c25:94de:18f0
2422c19:dd:d9:dd:c25:c25:94de:18f1/1282c19:dd:d9:dd:c25:c25:94de:18f1
2432c19:dd:d9:dd:c25:c25:94de:18f2/1282c19:dd:d9:dd:c25:c25:94de:18f2
2442c19:dd:d9:dd:c25:c25:94de:18f3/1282c19:dd:d9:dd:c25:c25:94de:18f3
2452c19:dd:d9:dd:c25:c25:94de:18f4/1282c19:dd:d9:dd:c25:c25:94de:18f4
2462c19:dd:d9:dd:c25:c25:94de:18f5/1282c19:dd:d9:dd:c25:c25:94de:18f5
2472c19:dd:d9:dd:c25:c25:94de:18f6/1282c19:dd:d9:dd:c25:c25:94de:18f6
2482c19:dd:d9:dd:c25:c25:94de:18f7/1282c19:dd:d9:dd:c25:c25:94de:18f7
2492c19:dd:d9:dd:c25:c25:94de:18f8/1282c19:dd:d9:dd:c25:c25:94de:18f8
2502c19:dd:d9:dd:c25:c25:94de:18f9/1282c19:dd:d9:dd:c25:c25:94de:18f9
2512c19:dd:d9:dd:c25:c25:94de:18fa/1282c19:dd:d9:dd:c25:c25:94de:18fa
2522c19:dd:d9:dd:c25:c25:94de:18fb/1282c19:dd:d9:dd:c25:c25:94de:18fb
2532c19:dd:d9:dd:c25:c25:94de:18fc/1282c19:dd:d9:dd:c25:c25:94de:18fc
2542c19:dd:d9:dd:c25:c25:94de:18fd/1282c19:dd:d9:dd:c25:c25:94de:18fd
2552c19:dd:d9:dd:c25:c25:94de:18fe/1282c19:dd:d9:dd:c25:c25:94de:18fe
2562c19:dd:d9:dd:c25:c25:94de:18ff/1282c19:dd:d9:dd:c25:c25:94de:18ff

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.