Find IP IPv4 Network/Subnet and its host address ranges

What is an IPv4 IP address its network and host address ranges?

An IPv4 IP address is an address used in order to uniquely identify a device on an IP network. The address is made up of 32 binary bits, which can be divisible into a network portion and host portion with the help of a subnet mask. The 32 binary bits are broken into four octets (1 octet = 8 bits). Each octet is converted to decimal and separated by a period (dot).

How to Subnet IPv4? Its simple answer is that subnetting is the process of taking a network and splitting it into smaller networks, known as subnets. It's used to free up more public IPv4 addresses and segment networks for security and easier management.
Following are the ranges of IPv4 subnet/network address and their host addresses.

IPv4 AddressIPv6 Address
21.237.43.1 0:0:0:0:0:ffff:15ed:2b01
21.237.43.2 0:0:0:0:0:ffff:15ed:2b02
21.237.43.3 0:0:0:0:0:ffff:15ed:2b03
21.237.43.4 0:0:0:0:0:ffff:15ed:2b04
21.237.43.5 0:0:0:0:0:ffff:15ed:2b05
21.237.43.6 0:0:0:0:0:ffff:15ed:2b06
21.237.43.7 0:0:0:0:0:ffff:15ed:2b07
21.237.43.8 0:0:0:0:0:ffff:15ed:2b08
21.237.43.9 0:0:0:0:0:ffff:15ed:2b09
21.237.43.10 0:0:0:0:0:ffff:15ed:2b0a
21.237.43.11 0:0:0:0:0:ffff:15ed:2b0b
21.237.43.12 0:0:0:0:0:ffff:15ed:2b0c
21.237.43.13 0:0:0:0:0:ffff:15ed:2b0d
21.237.43.14 0:0:0:0:0:ffff:15ed:2b0e
21.237.43.15 0:0:0:0:0:ffff:15ed:2b0f
21.237.43.16 0:0:0:0:0:ffff:15ed:2b10
21.237.43.17 0:0:0:0:0:ffff:15ed:2b11
21.237.43.18 0:0:0:0:0:ffff:15ed:2b12
21.237.43.19 0:0:0:0:0:ffff:15ed:2b13
21.237.43.20 0:0:0:0:0:ffff:15ed:2b14
21.237.43.21 0:0:0:0:0:ffff:15ed:2b15
21.237.43.22 0:0:0:0:0:ffff:15ed:2b16
21.237.43.23 0:0:0:0:0:ffff:15ed:2b17
21.237.43.24 0:0:0:0:0:ffff:15ed:2b18
21.237.43.25 0:0:0:0:0:ffff:15ed:2b19
21.237.43.26 0:0:0:0:0:ffff:15ed:2b1a
21.237.43.27 0:0:0:0:0:ffff:15ed:2b1b
21.237.43.28 0:0:0:0:0:ffff:15ed:2b1c
21.237.43.29 0:0:0:0:0:ffff:15ed:2b1d
21.237.43.30 0:0:0:0:0:ffff:15ed:2b1e
21.237.43.31 0:0:0:0:0:ffff:15ed:2b1f
21.237.43.32 0:0:0:0:0:ffff:15ed:2b20
21.237.43.33 0:0:0:0:0:ffff:15ed:2b21
21.237.43.34 0:0:0:0:0:ffff:15ed:2b22
21.237.43.35 0:0:0:0:0:ffff:15ed:2b23
21.237.43.36 0:0:0:0:0:ffff:15ed:2b24
21.237.43.37 0:0:0:0:0:ffff:15ed:2b25
21.237.43.38 0:0:0:0:0:ffff:15ed:2b26
21.237.43.39 0:0:0:0:0:ffff:15ed:2b27
21.237.43.40 0:0:0:0:0:ffff:15ed:2b28
21.237.43.41 0:0:0:0:0:ffff:15ed:2b29
21.237.43.42 0:0:0:0:0:ffff:15ed:2b2a
21.237.43.43 0:0:0:0:0:ffff:15ed:2b2b
21.237.43.44 0:0:0:0:0:ffff:15ed:2b2c
21.237.43.45 0:0:0:0:0:ffff:15ed:2b2d
21.237.43.46 0:0:0:0:0:ffff:15ed:2b2e
21.237.43.47 0:0:0:0:0:ffff:15ed:2b2f
21.237.43.48 0:0:0:0:0:ffff:15ed:2b30
21.237.43.49 0:0:0:0:0:ffff:15ed:2b31
21.237.43.50 0:0:0:0:0:ffff:15ed:2b32
21.237.43.51 0:0:0:0:0:ffff:15ed:2b33
21.237.43.52 0:0:0:0:0:ffff:15ed:2b34
21.237.43.53 0:0:0:0:0:ffff:15ed:2b35
21.237.43.54 0:0:0:0:0:ffff:15ed:2b36
21.237.43.55 0:0:0:0:0:ffff:15ed:2b37
21.237.43.56 0:0:0:0:0:ffff:15ed:2b38
21.237.43.57 0:0:0:0:0:ffff:15ed:2b39
21.237.43.58 0:0:0:0:0:ffff:15ed:2b3a
21.237.43.59 0:0:0:0:0:ffff:15ed:2b3b
21.237.43.60 0:0:0:0:0:ffff:15ed:2b3c


21.237.43.61 0:0:0:0:0:ffff:15ed:2b3d
21.237.43.62 0:0:0:0:0:ffff:15ed:2b3e
21.237.43.63 0:0:0:0:0:ffff:15ed:2b3f
21.237.43.64 0:0:0:0:0:ffff:15ed:2b40
21.237.43.65 0:0:0:0:0:ffff:15ed:2b41
21.237.43.66 0:0:0:0:0:ffff:15ed:2b42
21.237.43.67 0:0:0:0:0:ffff:15ed:2b43
21.237.43.68 0:0:0:0:0:ffff:15ed:2b44
21.237.43.69 0:0:0:0:0:ffff:15ed:2b45
21.237.43.70 0:0:0:0:0:ffff:15ed:2b46
21.237.43.71 0:0:0:0:0:ffff:15ed:2b47
21.237.43.72 0:0:0:0:0:ffff:15ed:2b48
21.237.43.73 0:0:0:0:0:ffff:15ed:2b49
21.237.43.74 0:0:0:0:0:ffff:15ed:2b4a
21.237.43.75 0:0:0:0:0:ffff:15ed:2b4b
21.237.43.76 0:0:0:0:0:ffff:15ed:2b4c
21.237.43.77 0:0:0:0:0:ffff:15ed:2b4d
21.237.43.78 0:0:0:0:0:ffff:15ed:2b4e
21.237.43.79 0:0:0:0:0:ffff:15ed:2b4f
21.237.43.80 0:0:0:0:0:ffff:15ed:2b50
21.237.43.81 0:0:0:0:0:ffff:15ed:2b51
21.237.43.82 0:0:0:0:0:ffff:15ed:2b52
21.237.43.83 0:0:0:0:0:ffff:15ed:2b53
21.237.43.84 0:0:0:0:0:ffff:15ed:2b54
21.237.43.85 0:0:0:0:0:ffff:15ed:2b55
21.237.43.86 0:0:0:0:0:ffff:15ed:2b56
21.237.43.87 0:0:0:0:0:ffff:15ed:2b57
21.237.43.88 0:0:0:0:0:ffff:15ed:2b58
21.237.43.89 0:0:0:0:0:ffff:15ed:2b59
21.237.43.90 0:0:0:0:0:ffff:15ed:2b5a
21.237.43.91 0:0:0:0:0:ffff:15ed:2b5b
21.237.43.92 0:0:0:0:0:ffff:15ed:2b5c
21.237.43.93 0:0:0:0:0:ffff:15ed:2b5d
21.237.43.94 0:0:0:0:0:ffff:15ed:2b5e
21.237.43.95 0:0:0:0:0:ffff:15ed:2b5f
21.237.43.96 0:0:0:0:0:ffff:15ed:2b60
21.237.43.97 0:0:0:0:0:ffff:15ed:2b61
21.237.43.98 0:0:0:0:0:ffff:15ed:2b62
21.237.43.99 0:0:0:0:0:ffff:15ed:2b63
21.237.43.100 0:0:0:0:0:ffff:15ed:2b64
21.237.43.101 0:0:0:0:0:ffff:15ed:2b65
21.237.43.102 0:0:0:0:0:ffff:15ed:2b66
21.237.43.103 0:0:0:0:0:ffff:15ed:2b67
21.237.43.104 0:0:0:0:0:ffff:15ed:2b68
21.237.43.105 0:0:0:0:0:ffff:15ed:2b69
21.237.43.106 0:0:0:0:0:ffff:15ed:2b6a
21.237.43.107 0:0:0:0:0:ffff:15ed:2b6b
21.237.43.108 0:0:0:0:0:ffff:15ed:2b6c
21.237.43.109 0:0:0:0:0:ffff:15ed:2b6d
21.237.43.110 0:0:0:0:0:ffff:15ed:2b6e
21.237.43.111 0:0:0:0:0:ffff:15ed:2b6f
21.237.43.112 0:0:0:0:0:ffff:15ed:2b70
21.237.43.113 0:0:0:0:0:ffff:15ed:2b71
21.237.43.114 0:0:0:0:0:ffff:15ed:2b72
21.237.43.115 0:0:0:0:0:ffff:15ed:2b73
21.237.43.116 0:0:0:0:0:ffff:15ed:2b74
21.237.43.117 0:0:0:0:0:ffff:15ed:2b75
21.237.43.118 0:0:0:0:0:ffff:15ed:2b76
21.237.43.119 0:0:0:0:0:ffff:15ed:2b77
21.237.43.120 0:0:0:0:0:ffff:15ed:2b78


21.237.43.121 0:0:0:0:0:ffff:15ed:2b79
21.237.43.122 0:0:0:0:0:ffff:15ed:2b7a
21.237.43.123 0:0:0:0:0:ffff:15ed:2b7b
21.237.43.124 0:0:0:0:0:ffff:15ed:2b7c
21.237.43.125 0:0:0:0:0:ffff:15ed:2b7d
21.237.43.126 0:0:0:0:0:ffff:15ed:2b7e
21.237.43.127 0:0:0:0:0:ffff:15ed:2b7f
21.237.43.128 0:0:0:0:0:ffff:15ed:2b80
21.237.43.129 0:0:0:0:0:ffff:15ed:2b81
21.237.43.130 0:0:0:0:0:ffff:15ed:2b82
21.237.43.131 0:0:0:0:0:ffff:15ed:2b83
21.237.43.132 0:0:0:0:0:ffff:15ed:2b84
21.237.43.133 0:0:0:0:0:ffff:15ed:2b85
21.237.43.134 0:0:0:0:0:ffff:15ed:2b86
21.237.43.135 0:0:0:0:0:ffff:15ed:2b87
21.237.43.136 0:0:0:0:0:ffff:15ed:2b88
21.237.43.137 0:0:0:0:0:ffff:15ed:2b89
21.237.43.138 0:0:0:0:0:ffff:15ed:2b8a
21.237.43.139 0:0:0:0:0:ffff:15ed:2b8b
21.237.43.140 0:0:0:0:0:ffff:15ed:2b8c
21.237.43.141 0:0:0:0:0:ffff:15ed:2b8d
21.237.43.142 0:0:0:0:0:ffff:15ed:2b8e
21.237.43.143 0:0:0:0:0:ffff:15ed:2b8f
21.237.43.144 0:0:0:0:0:ffff:15ed:2b90
21.237.43.145 0:0:0:0:0:ffff:15ed:2b91
21.237.43.146 0:0:0:0:0:ffff:15ed:2b92
21.237.43.147 0:0:0:0:0:ffff:15ed:2b93
21.237.43.148 0:0:0:0:0:ffff:15ed:2b94
21.237.43.149 0:0:0:0:0:ffff:15ed:2b95
21.237.43.150 0:0:0:0:0:ffff:15ed:2b96
21.237.43.151 0:0:0:0:0:ffff:15ed:2b97
21.237.43.152 0:0:0:0:0:ffff:15ed:2b98
21.237.43.153 0:0:0:0:0:ffff:15ed:2b99
21.237.43.154 0:0:0:0:0:ffff:15ed:2b9a
21.237.43.155 0:0:0:0:0:ffff:15ed:2b9b
21.237.43.156 0:0:0:0:0:ffff:15ed:2b9c
21.237.43.157 0:0:0:0:0:ffff:15ed:2b9d
21.237.43.158 0:0:0:0:0:ffff:15ed:2b9e
21.237.43.159 0:0:0:0:0:ffff:15ed:2b9f
21.237.43.160 0:0:0:0:0:ffff:15ed:2ba0
21.237.43.161 0:0:0:0:0:ffff:15ed:2ba1
21.237.43.162 0:0:0:0:0:ffff:15ed:2ba2
21.237.43.163 0:0:0:0:0:ffff:15ed:2ba3
21.237.43.164 0:0:0:0:0:ffff:15ed:2ba4
21.237.43.165 0:0:0:0:0:ffff:15ed:2ba5
21.237.43.166 0:0:0:0:0:ffff:15ed:2ba6
21.237.43.167 0:0:0:0:0:ffff:15ed:2ba7
21.237.43.168 0:0:0:0:0:ffff:15ed:2ba8
21.237.43.169 0:0:0:0:0:ffff:15ed:2ba9
21.237.43.170 0:0:0:0:0:ffff:15ed:2baa
21.237.43.171 0:0:0:0:0:ffff:15ed:2bab
21.237.43.172 0:0:0:0:0:ffff:15ed:2bac
21.237.43.173 0:0:0:0:0:ffff:15ed:2bad
21.237.43.174 0:0:0:0:0:ffff:15ed:2bae
21.237.43.175 0:0:0:0:0:ffff:15ed:2baf
21.237.43.176 0:0:0:0:0:ffff:15ed:2bb0
21.237.43.177 0:0:0:0:0:ffff:15ed:2bb1
21.237.43.178 0:0:0:0:0:ffff:15ed:2bb2
21.237.43.179 0:0:0:0:0:ffff:15ed:2bb3
21.237.43.180 0:0:0:0:0:ffff:15ed:2bb4


21.237.43.181 0:0:0:0:0:ffff:15ed:2bb5
21.237.43.182 0:0:0:0:0:ffff:15ed:2bb6
21.237.43.183 0:0:0:0:0:ffff:15ed:2bb7
21.237.43.184 0:0:0:0:0:ffff:15ed:2bb8
21.237.43.185 0:0:0:0:0:ffff:15ed:2bb9
21.237.43.186 0:0:0:0:0:ffff:15ed:2bba
21.237.43.187 0:0:0:0:0:ffff:15ed:2bbb
21.237.43.188 0:0:0:0:0:ffff:15ed:2bbc
21.237.43.189 0:0:0:0:0:ffff:15ed:2bbd
21.237.43.190 0:0:0:0:0:ffff:15ed:2bbe
21.237.43.191 0:0:0:0:0:ffff:15ed:2bbf
21.237.43.192 0:0:0:0:0:ffff:15ed:2bc0
21.237.43.193 0:0:0:0:0:ffff:15ed:2bc1
21.237.43.194 0:0:0:0:0:ffff:15ed:2bc2
21.237.43.195 0:0:0:0:0:ffff:15ed:2bc3
21.237.43.196 0:0:0:0:0:ffff:15ed:2bc4
21.237.43.197 0:0:0:0:0:ffff:15ed:2bc5
21.237.43.198 0:0:0:0:0:ffff:15ed:2bc6
21.237.43.199 0:0:0:0:0:ffff:15ed:2bc7
21.237.43.200 0:0:0:0:0:ffff:15ed:2bc8
21.237.43.201 0:0:0:0:0:ffff:15ed:2bc9
21.237.43.202 0:0:0:0:0:ffff:15ed:2bca
21.237.43.203 0:0:0:0:0:ffff:15ed:2bcb
21.237.43.204 0:0:0:0:0:ffff:15ed:2bcc
21.237.43.205 0:0:0:0:0:ffff:15ed:2bcd
21.237.43.206 0:0:0:0:0:ffff:15ed:2bce
21.237.43.207 0:0:0:0:0:ffff:15ed:2bcf
21.237.43.208 0:0:0:0:0:ffff:15ed:2bd0
21.237.43.209 0:0:0:0:0:ffff:15ed:2bd1
21.237.43.210 0:0:0:0:0:ffff:15ed:2bd2
21.237.43.211 0:0:0:0:0:ffff:15ed:2bd3
21.237.43.212 0:0:0:0:0:ffff:15ed:2bd4
21.237.43.213 0:0:0:0:0:ffff:15ed:2bd5
21.237.43.214 0:0:0:0:0:ffff:15ed:2bd6
21.237.43.215 0:0:0:0:0:ffff:15ed:2bd7
21.237.43.216 0:0:0:0:0:ffff:15ed:2bd8
21.237.43.217 0:0:0:0:0:ffff:15ed:2bd9
21.237.43.218 0:0:0:0:0:ffff:15ed:2bda
21.237.43.219 0:0:0:0:0:ffff:15ed:2bdb
21.237.43.220 0:0:0:0:0:ffff:15ed:2bdc
21.237.43.221 0:0:0:0:0:ffff:15ed:2bdd
21.237.43.222 0:0:0:0:0:ffff:15ed:2bde
21.237.43.223 0:0:0:0:0:ffff:15ed:2bdf
21.237.43.224 0:0:0:0:0:ffff:15ed:2be0
21.237.43.225 0:0:0:0:0:ffff:15ed:2be1
21.237.43.226 0:0:0:0:0:ffff:15ed:2be2
21.237.43.227 0:0:0:0:0:ffff:15ed:2be3
21.237.43.228 0:0:0:0:0:ffff:15ed:2be4
21.237.43.229 0:0:0:0:0:ffff:15ed:2be5
21.237.43.230 0:0:0:0:0:ffff:15ed:2be6
21.237.43.231 0:0:0:0:0:ffff:15ed:2be7
21.237.43.232 0:0:0:0:0:ffff:15ed:2be8
21.237.43.233 0:0:0:0:0:ffff:15ed:2be9
21.237.43.234 0:0:0:0:0:ffff:15ed:2bea
21.237.43.235 0:0:0:0:0:ffff:15ed:2beb
21.237.43.236 0:0:0:0:0:ffff:15ed:2bec
21.237.43.237 0:0:0:0:0:ffff:15ed:2bed
21.237.43.238 0:0:0:0:0:ffff:15ed:2bee
21.237.43.239 0:0:0:0:0:ffff:15ed:2bef
21.237.43.240 0:0:0:0:0:ffff:15ed:2bf0
21.237.43.241 0:0:0:0:0:ffff:15ed:2bf1
21.237.43.242 0:0:0:0:0:ffff:15ed:2bf2
21.237.43.243 0:0:0:0:0:ffff:15ed:2bf3
21.237.43.244 0:0:0:0:0:ffff:15ed:2bf4
21.237.43.245 0:0:0:0:0:ffff:15ed:2bf5
21.237.43.246 0:0:0:0:0:ffff:15ed:2bf6
21.237.43.247 0:0:0:0:0:ffff:15ed:2bf7
21.237.43.248 0:0:0:0:0:ffff:15ed:2bf8
21.237.43.249 0:0:0:0:0:ffff:15ed:2bf9
21.237.43.250 0:0:0:0:0:ffff:15ed:2bfa
21.237.43.251 0:0:0:0:0:ffff:15ed:2bfb
21.237.43.252 0:0:0:0:0:ffff:15ed:2bfc
21.237.43.253 0:0:0:0:0:ffff:15ed:2bfd
21.237.43.254 0:0:0:0:0:ffff:15ed:2bfe
21.237.43.255 0:0:0:0:0:ffff:15ed:2bff


How we got IPv4 subnet masks?

An IPv4 subnet mask consists of 32 bits; it is a sequence of ones (1) followed by a block of zeros (0). The ones indicate bits in the address used for the network prefix and the trailing block of zeros designates that part as being the host identifier.