IP Address Ranges

-see tables below-

Class As

Ever wonder who owns the class A IP networks? These are the blocks of addresses with initial octet 1 through 128, and they are allocated entirely to one organization (or used to be, anyway). For example, IBM owns all the addresses from 9.0.0.0 to 9.255.255.255. This range can hold approximately 16 million individual hosts (computers). Class A networks are almost never given out anymore, since very few organizations can actually use all those addresses. Anyway, here's the list: 
Number	Organization
------  ------------
 3	General Electric
 4	BBN Planet 
 6	Army Information Systems Center 
 8	BBN (corporate)
 9	IBM
11	DoD Intel Information Systems 
12	AT&T
13	Xerox PARC
14	Public Data Network 
15	HP
16	DEC
17	Apple
18	MIT
19	Ford
20	Computer Sciences Corporation 
21	DDN-RVN 
22	Defense Information Systems Agency 
25	Royal Signals and Radar Establishment 
26	Defense Information Systems Agency 
28	ARPA DSI JPO 
29	Defense Information Systems Agency 
30	Defense Information Systems Agency 
32	Norsk Informasjonsteknologi 
33	DLA Systems Automation Center 
34	Halliburton Co.
35	Merit Network Inc. 
36	Stanford
38	PSI
40	Eli Lilly and Co.
43	Japan Inet 
44	Amateur Radio Digital Communications 
45	Interop Show Network 
47	Bell-Northern Research 
48	Prudential
49	Joint Tactical Command, Control and Communications Agency 
51	Department of Social Security of UK 
52	Du Pont
53	cap debis ccs 
54	Merck
55	Army National Guard Bureau 
56	U.S. Postal Service 
57	Societe Internationale de Telecommunications Aeronautiques 
61	Asia Pacific Network Information Center 
62	European Regional Internet Registry/RIPE NCC 
63	InterNIC
Most of these organizations were involved in the early development of the Internet, so they got networks assigned before IANA (Internet Assigned Numbers Authority) stopped giving out class As. Several are assigned to military organizations, but I think it's a bit of a stretch to claim "the only people with class A networks also have nuclear weapons," as I saw someone assert somewhere (typical net.hyperbole)
Class Bs
Class B - Class B is used for medium-sized networks. A good example is a large college campus. IP addresses with a first octet from 128 to 191 are part of this class. Range 128.x.x.x to 191.x.x.x
Class Cs

To communicate on the Internet, you must use addresses that have been allocated by the Internet Network Information Center (InterNIC). Addresses allocated by InterNIC can receive traffic from Internet locations and are known as public addresses. A typical small business or home office is allocated a public address (or addresses) from its Internet service provider (ISP), who has received a range of public addresses.

To allow multiple computers in the small office or home office to communicate on the Internet, each computer must have its own public address. This requirement places great stress on the available pool of public addresses.

To relieve this stress, the InterNIC has provided for an address reuse scheme by reserving network IDs for private internetworks. The private network IDs include:

For more information about portions of the IP address space that is reserved for private intranets, see RFC 1597, "Address Allocation for Private Internets." All addresses in these ranges are known as private addresses.

Private addresses cannot receive traffic from Internet locations. Therefore, if an intranet is using private addresses and communicating with Internet locations, the private address must be translated to a public address. A network address translator (NAT) is placed between an intranet that uses private addresses and the Internet, which uses public addresses. Outgoing packets from the intranet have their private addresses translated by the NAT into public addresses. Incoming packets from the Internet have their public addresses translated by the NAT into private addresses. This is what simple home routers use.

Loopback - The IP address
127.0.0.0 is used as the loopback address. This means that it is used by the host computer to send a message back to itself. It is commonly used for troubleshooting and network testing.

Class D - Used for multicasts, Class D is slightly different from the first three classes. 224. 24.53.107

Class E - Class E is used for experimental purposes only. Like Class D, it is different from the first three classes. Net Host or Node 232. 24.53.107

Broadcast - Messages that are intended for all computers on a network are sent as broadcasts. These messages always use the IP address 255.255.255.255.

 

IP Address Tables

 

Listed below are the IP address tables for Class A, Class B and Class C. Each table presents:

The Maximum number of Subnets for a given mask
The Maximum number of hosts for a given mask
The first and second subnet information,as follows:
The Subnet number which is used for routing (this is the number displayed in routing tables)
The valid IP address ranges for the subnets
The IP subnet broadcast address
Please note, the information on the first and last subnets has not been displayed as some hosts are unable to use these subnets, see RFC 1519 or 1812 for more information
No liability is taken for the correctness of the information supplied on this page or any other page.

 

Class A IP Address Table

No: of Subnet bits

Subnet Mask

 Subnet Mask in Hex

No: Subnets

No: Hosts

Max No: of Hosts (Nets * Hosts)

 1st Subnet Addr. Used for Routing 1st Subnet Addr Range 1st Subnet B'cast 2nd Subnet Addr. Used for Routing 2nd Subnet Addr Range 2nd Subnet B'cast

2

255.192.0.0

 FF.C0.0.0

2

4194302

8388604

X.64.0.0

X.64.0.1 to X.127.255.254

X.127.255.255

X.128.0.0

X.128.0.1 to X.191.255.254

X.191.255.255

3

255.224.0.0

 FF.E0.0.0

6

2097150

12582900

X.32.0.0

X.32.0.1 to X.63.255.254

X.63.255.255

X.64.0.0 

X.64.0.1 to X.95.0.254 

X.95.255.255 

4

255.240.0.0

 FF.F0.0.0

14

1048574

14680036

  X.16.0.0

  X.16.0.1 to X.31.255.254

X.31.255.255 

X.32.0.0 

X.32.0.1 to X.47.255.254 

  X.47.255.255

5

255.248.0.0

 FF.F8.0.0

30

524286

15728580

  X.8.0.0

X.8.0.1 to X.15.255.254

X.15.255.255

X.16.0.0

X.16.0.1 to X.23.255.254

X.23.255.255

6

255.252.0.0

 FF.FC.0.0

62

262142

16252804

  X.4.0.0

X.4.0.1 to X.7.255.254

X.7.255.255

X.8.0.0

X.8.0.1 to X.11.255.254

X.11.255.255

7

255.254.0.0

 FF.FE.0.0

126

131070

16514820

X.2.0.0 

X.2.0.1 to X.3.255.254

X.3.255.255

X.4.0.0

X.4.0.1 to X.5.255.254

X.5.255.255

8

255.255.0.0

 FF.FF.0.0

254

65534

16645636

  X.1.0.0

X.1.0.1 to X.1.255.254

X.1.255.255

X.2.0.0 

X.2.0.1 to X.2.255.254

 X.2.255.255

9

255.255.128.0

 FF.FF.80.0

510

32766

16710660

X.0.128.0

X.0.128.1 to X.0.255.254

X.0.255.255 

X.1.0.0 

X.1.0.1 to X.1.127.254

X.1.127.255 

10

255.255.192.0

 FF.FF.C0.0

1022

16382

16742404

  X.0.64.0

X.0.64.1 to X.0.127.254 

X.0.127.255 

X.0.128.0 

X.0.128.1 to X.0.191.254 

X.0.191.255 

11

255.255.224.0

 FF.FF.E0.0

2046

8190

16756740

  X.0.32.0

  X.0.32.1 to X.0.63.254

X.0.63.255 

X.0.64.0 

X.0.64.1 to X.0.95.254 

X.0.95.255 

12

255.255.240.0

 FF.FF.F0.0

4094

4094

16760836

X.0.16.0 

X.0.16.1 to X.0.31.254 

X.0.31.255 

X.0.32.0 

X.0.32.1 to X.0.47.254 

X.0.47.255 

13

255.255.248.0

 FF.FF.F8.0

8190

2046

16756740

X.0.8.0

X.0.8.1 to X.0.15.254 

X.0.15.255 

X.0.16.0 

X.0.16.1 to X.0.23.254 

X.0.23.255 

14

255.255.252.0

 FF.FF.FC.0

16382

1022

16742404

  X.0.4.0

X.0.4.1 to X.0.7.254 

X.0.7.255 

 X.0.8.0

X.0.8.1 to X.0.11.254 

 X.0.11.255

15

255.255.254.0

 FF.FF.FE.0

32766

510

16710660

 X.0.2.0

X.0.2.1 to X.0.3.254 

X.0.3.255

X.0.4.0

X.0.4.1 to X.0.5.254

X.0.5.255

16

255.255.255.0

 FF.FF.FF.0

65534

254

16645636

X.0.1.0

X.0.1.1 to X.0.1.254 

X.0.1.255 

X.0.2.0 

X.0.2.1 to X.0.2.254 

X.0.2.255 

17

255.255.255.128

 FF.FF.FF.80

131070

126

16514820

X.0.0.128

X.0.0.129 to X.0.0.254 

X.0.0.255 

X.0.1.0 

X.0.1.1 to X.0.1.126

  X.0.1.127

18

255.255.255.192

 FF.FF.FF.C0

262142

62

16252804

 X.0.0.64

X.0.0.65 to X.0.0.126 

  X.0.0.127

X.0.0.128 

X.0.0.129 to X.0.0.190 

X.0.0.191 

19

255.255.255.224

 FF.FF.FF.E0

524286

30

15728580

  X.0.0.32

X.0.0.33 to X.0.0.62 

  X.0.0.63

X.0.0.64 

X.0.0.65 to X.0.0.94 

X.0.0.95 

20

255.255.255.240

 FF.FF.FF.F0

1048574

14

14680036

  X.0.0.16

X.0.0.17 to X.0.0.30 

X.0.0.31 

X.0.0.32 

X.0.0.33 to X.0.0.46 

X.0.0.47 

21

255.255.255.248

 FF.FF.FF.F8

2097150

6

12582900

  X.0.0.8

X.0.0.9 to X.0.0.14 

X.0.0.15 

X.0.0.16 

X.0.0.17 to X.0.0.22 

X.0.0.23 

22

255.255.255.252

 FF.FF.FF.FC

4194302

2

8388604

  X.0.0.4

X.0.0.5   to X.0.0.6 

X.0.0.7 

X.0.0.8 

X.0.0.9 to X.0.0.10 

X.0.0.11 

 

 

  

 

 

Class B IP Address Table

tNo: of Subnet bitss

Subnet Mask

 Subnet Mask in Hex

No: Subnets

No: Hosts

Max No: of Hosts (Nets * Hosts)

 1st Subnet Addr. Used for Routing 1st Subnet Addr Range 1st Subnet B'cast 2nd Subnet Addr. Used for Routing 2nd Subnet Addr Range 2nd Subnet B'cast

2

255.255.192.0

 FF.FF.C0.0

2

16382

32764

X.Y.64.0

X.Y.64.1   to X.Y.127.254

X.Y.127.255

X.Y.128.0

X.Y.128.1 to X.Y.191.254

X.Y.191.255

3

255.255.224.0

 FF.FF.E0.0

6

8190

49140

X.Y.32.0

X.Y.32.1 to X.Y.63.254

X.Y.63.255

X.Y.64.0

X.Y.64.1 to X.Y.95.254

X.Y.95.255

4

255.255.240.0

 FF.FF.F0.0

14

4094

57316

X.Y.16.0

X.Y.16.1 to X.Y.31.254

X.Y.31.255

X.Y.32.0

X.Y.32.1 to X.Y.47.254

X.Y.47.255

5

255.255.248.0

 FF.FF.F8.0

30

2046

61380

X.Y.8.0

X.Y.8.1 to X.Y.15.254

X.Y.15.255

X.Y.16.0

X.Y.16.1 to X.Y.23.254

X.Y.23.255

6

255.255.252.0

 FF.FF.FC.0

62

1022

63364

X.Y.4.0

X.Y.4.1 to X.Y.7.254

X.Y.7.255

X.Y.8.0

X.Y.8.1 to X.Y.11.254

X.Y.11.255

7

255.255.254.0

 FF.FF.FE.0

126

510

64260

X.Y.2.0

X.Y.2.1 to X.Y.3.254

X.Y.3.255

X.Y.4.0

X.Y.4.1 to X.Y.5.254

X.Y.5.255

8

255.255.255.0

 FF.FF.FF.0

254

254

64516

X.Y.1.0

X.Y.1.1 to X.Y.254

X.Y.1.255

X.Y.2.0

X.Y.2.1 to X.Y.2.254

X.Y.2.255

9

255.255.255.128

 FF.FF.FF.80

510

126

64260

X.Y.0.128

X.Y.0.129 to X.Y.0.254

X.Y.0.255

X.Y.1.0

X.Y.1.1 to X.Y.1.126

X.Y.1.127

10

255.255.255.192

 FF.FF.FF.C0

1022

62

63364

X.Y.0.64

X.Y.0.65 to X.Y.0.126

X.Y.0.127

X.Y.0.128

X.Y.0.129 to X.Y.0.190

X.Y.0.191

11

255.255.255.224

 FF.FF.FF.E0

2046

30

61380

X.Y.0.32

X.Y.0.33 to X.Y.0.62

X.Y.0.63

X.Y.0.64

X.Y.0.65 to X.Y.0.94

X.Y.0.95

12

255.255.255.240

 FF.FF.FF.F0

4094

14

57316

X.Y.0.16

X.Y.0.17 to X.Y.0.30

X.Y.0.31

X.Y.0.32

X.Y.0.33 to X.Y.0.46

X.Y.0.47

13

255.255.255.248

 FF.FF.FF.F8

8190

6

49140

X.Y.0.8

X.Y.0.9 to X.Y.0.14

X.Y.0.15

X.Y.0.16

X.Y.0.17 to X.Y.0.22

X.Y.0.23

14

255.255.255.252

 FF.FF.FF.FC

16382

2

32764

X.Y.0.4

X.Y.0.5 to X.Y.0.6

X.Y.0.7

X.Y.0.8

X.Y.0.9 to X.Y.0.10

X.Y.0.11

 

 

 

Class C IP Address Table

No: of Subnet bits

Subnet Mask

 Subnet Mask in Hex

No: Subnets

No: Hosts

Max No: of Hosts (Nets * Hosts)

 1st Subnet Addr. Used for Routing 1st Subnet Addr Range 1st Subnet B'cast 2nd Subnet Addr. Used for Routing 2nd Subnet Addr Range 2nd Subnet B'cast

2

255.255.255.192

 FF.FF.FF.C0

2

62

124

X.Y.Z.64

X.Y.Z.65 to X.Y.Z.126

X.Y.Z.127

X.Y.Z.128

X.Y.Z.129 to X.Y.Z.190

X.Y.Z.191

3

255.255.255.224

 FF.FF.FF.E0

6

30

180

X.Y.Z.32

X.Y.Z.33 to X.Y.Z.62

X.Y.Z.63

X.Y.Z.64

X.Y.Z.65 to X.Y.Z.94

X.Y.Z.95

4

255.255.255.240

 FF.FF.FF.F0

14

14

196

X.Y.Z.16

X.Y.Z.17 to X.Y.Z.30

X.Y.Z.31

X.Y.Z.32

X.Y.Z.33 to X.Y.Z.46

X.Y.Z.47

5

255.255.255.248

 FF.FF.FF.F8

30

6

180

X.Y.Z.8

X.Y.Z.9  to X.Y.Z.14

X.Y.Z.15

X.Y.Z.16

X.Y.Z.17 to X.Y.Z.22

X.Y.Z.23

6

255.255.255.252

 FF.FF.FF.FC

62

2

124

X.Y.Z.4

X.Y.Z.5 to X.Y.Z.6

X.Y.Z.7

X.Y.Z.8

X.Y.Z.9  to X.Y.Z.10

X.Y.Z.11