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
128.21.55.1 0:0:0:0:0:ffff:8015:3701
128.21.55.2 0:0:0:0:0:ffff:8015:3702
128.21.55.3 0:0:0:0:0:ffff:8015:3703
128.21.55.4 0:0:0:0:0:ffff:8015:3704
128.21.55.5 0:0:0:0:0:ffff:8015:3705
128.21.55.6 0:0:0:0:0:ffff:8015:3706
128.21.55.7 0:0:0:0:0:ffff:8015:3707
128.21.55.8 0:0:0:0:0:ffff:8015:3708
128.21.55.9 0:0:0:0:0:ffff:8015:3709
128.21.55.10 0:0:0:0:0:ffff:8015:370a
128.21.55.11 0:0:0:0:0:ffff:8015:370b
128.21.55.12 0:0:0:0:0:ffff:8015:370c
128.21.55.13 0:0:0:0:0:ffff:8015:370d
128.21.55.14 0:0:0:0:0:ffff:8015:370e
128.21.55.15 0:0:0:0:0:ffff:8015:370f
128.21.55.16 0:0:0:0:0:ffff:8015:3710
128.21.55.17 0:0:0:0:0:ffff:8015:3711
128.21.55.18 0:0:0:0:0:ffff:8015:3712
128.21.55.19 0:0:0:0:0:ffff:8015:3713
128.21.55.20 0:0:0:0:0:ffff:8015:3714
128.21.55.21 0:0:0:0:0:ffff:8015:3715
128.21.55.22 0:0:0:0:0:ffff:8015:3716
128.21.55.23 0:0:0:0:0:ffff:8015:3717
128.21.55.24 0:0:0:0:0:ffff:8015:3718
128.21.55.25 0:0:0:0:0:ffff:8015:3719
128.21.55.26 0:0:0:0:0:ffff:8015:371a
128.21.55.27 0:0:0:0:0:ffff:8015:371b
128.21.55.28 0:0:0:0:0:ffff:8015:371c
128.21.55.29 0:0:0:0:0:ffff:8015:371d
128.21.55.30 0:0:0:0:0:ffff:8015:371e
128.21.55.31 0:0:0:0:0:ffff:8015:371f
128.21.55.32 0:0:0:0:0:ffff:8015:3720
128.21.55.33 0:0:0:0:0:ffff:8015:3721
128.21.55.34 0:0:0:0:0:ffff:8015:3722
128.21.55.35 0:0:0:0:0:ffff:8015:3723
128.21.55.36 0:0:0:0:0:ffff:8015:3724
128.21.55.37 0:0:0:0:0:ffff:8015:3725
128.21.55.38 0:0:0:0:0:ffff:8015:3726
128.21.55.39 0:0:0:0:0:ffff:8015:3727
128.21.55.40 0:0:0:0:0:ffff:8015:3728
128.21.55.41 0:0:0:0:0:ffff:8015:3729
128.21.55.42 0:0:0:0:0:ffff:8015:372a
128.21.55.43 0:0:0:0:0:ffff:8015:372b
128.21.55.44 0:0:0:0:0:ffff:8015:372c
128.21.55.45 0:0:0:0:0:ffff:8015:372d
128.21.55.46 0:0:0:0:0:ffff:8015:372e
128.21.55.47 0:0:0:0:0:ffff:8015:372f
128.21.55.48 0:0:0:0:0:ffff:8015:3730
128.21.55.49 0:0:0:0:0:ffff:8015:3731
128.21.55.50 0:0:0:0:0:ffff:8015:3732
128.21.55.51 0:0:0:0:0:ffff:8015:3733
128.21.55.52 0:0:0:0:0:ffff:8015:3734
128.21.55.53 0:0:0:0:0:ffff:8015:3735
128.21.55.54 0:0:0:0:0:ffff:8015:3736
128.21.55.55 0:0:0:0:0:ffff:8015:3737
128.21.55.56 0:0:0:0:0:ffff:8015:3738
128.21.55.57 0:0:0:0:0:ffff:8015:3739
128.21.55.58 0:0:0:0:0:ffff:8015:373a
128.21.55.59 0:0:0:0:0:ffff:8015:373b
128.21.55.60 0:0:0:0:0:ffff:8015:373c


128.21.55.61 0:0:0:0:0:ffff:8015:373d
128.21.55.62 0:0:0:0:0:ffff:8015:373e
128.21.55.63 0:0:0:0:0:ffff:8015:373f
128.21.55.64 0:0:0:0:0:ffff:8015:3740
128.21.55.65 0:0:0:0:0:ffff:8015:3741
128.21.55.66 0:0:0:0:0:ffff:8015:3742
128.21.55.67 0:0:0:0:0:ffff:8015:3743
128.21.55.68 0:0:0:0:0:ffff:8015:3744
128.21.55.69 0:0:0:0:0:ffff:8015:3745
128.21.55.70 0:0:0:0:0:ffff:8015:3746
128.21.55.71 0:0:0:0:0:ffff:8015:3747
128.21.55.72 0:0:0:0:0:ffff:8015:3748
128.21.55.73 0:0:0:0:0:ffff:8015:3749
128.21.55.74 0:0:0:0:0:ffff:8015:374a
128.21.55.75 0:0:0:0:0:ffff:8015:374b
128.21.55.76 0:0:0:0:0:ffff:8015:374c
128.21.55.77 0:0:0:0:0:ffff:8015:374d
128.21.55.78 0:0:0:0:0:ffff:8015:374e
128.21.55.79 0:0:0:0:0:ffff:8015:374f
128.21.55.80 0:0:0:0:0:ffff:8015:3750
128.21.55.81 0:0:0:0:0:ffff:8015:3751
128.21.55.82 0:0:0:0:0:ffff:8015:3752
128.21.55.83 0:0:0:0:0:ffff:8015:3753
128.21.55.84 0:0:0:0:0:ffff:8015:3754
128.21.55.85 0:0:0:0:0:ffff:8015:3755
128.21.55.86 0:0:0:0:0:ffff:8015:3756
128.21.55.87 0:0:0:0:0:ffff:8015:3757
128.21.55.88 0:0:0:0:0:ffff:8015:3758
128.21.55.89 0:0:0:0:0:ffff:8015:3759
128.21.55.90 0:0:0:0:0:ffff:8015:375a
128.21.55.91 0:0:0:0:0:ffff:8015:375b
128.21.55.92 0:0:0:0:0:ffff:8015:375c
128.21.55.93 0:0:0:0:0:ffff:8015:375d
128.21.55.94 0:0:0:0:0:ffff:8015:375e
128.21.55.95 0:0:0:0:0:ffff:8015:375f
128.21.55.96 0:0:0:0:0:ffff:8015:3760
128.21.55.97 0:0:0:0:0:ffff:8015:3761
128.21.55.98 0:0:0:0:0:ffff:8015:3762
128.21.55.99 0:0:0:0:0:ffff:8015:3763
128.21.55.100 0:0:0:0:0:ffff:8015:3764
128.21.55.101 0:0:0:0:0:ffff:8015:3765
128.21.55.102 0:0:0:0:0:ffff:8015:3766
128.21.55.103 0:0:0:0:0:ffff:8015:3767
128.21.55.104 0:0:0:0:0:ffff:8015:3768
128.21.55.105 0:0:0:0:0:ffff:8015:3769
128.21.55.106 0:0:0:0:0:ffff:8015:376a
128.21.55.107 0:0:0:0:0:ffff:8015:376b
128.21.55.108 0:0:0:0:0:ffff:8015:376c
128.21.55.109 0:0:0:0:0:ffff:8015:376d
128.21.55.110 0:0:0:0:0:ffff:8015:376e
128.21.55.111 0:0:0:0:0:ffff:8015:376f
128.21.55.112 0:0:0:0:0:ffff:8015:3770
128.21.55.113 0:0:0:0:0:ffff:8015:3771
128.21.55.114 0:0:0:0:0:ffff:8015:3772
128.21.55.115 0:0:0:0:0:ffff:8015:3773
128.21.55.116 0:0:0:0:0:ffff:8015:3774
128.21.55.117 0:0:0:0:0:ffff:8015:3775
128.21.55.118 0:0:0:0:0:ffff:8015:3776
128.21.55.119 0:0:0:0:0:ffff:8015:3777
128.21.55.120 0:0:0:0:0:ffff:8015:3778


128.21.55.121 0:0:0:0:0:ffff:8015:3779
128.21.55.122 0:0:0:0:0:ffff:8015:377a
128.21.55.123 0:0:0:0:0:ffff:8015:377b
128.21.55.124 0:0:0:0:0:ffff:8015:377c
128.21.55.125 0:0:0:0:0:ffff:8015:377d
128.21.55.126 0:0:0:0:0:ffff:8015:377e
128.21.55.127 0:0:0:0:0:ffff:8015:377f
128.21.55.128 0:0:0:0:0:ffff:8015:3780
128.21.55.129 0:0:0:0:0:ffff:8015:3781
128.21.55.130 0:0:0:0:0:ffff:8015:3782
128.21.55.131 0:0:0:0:0:ffff:8015:3783
128.21.55.132 0:0:0:0:0:ffff:8015:3784
128.21.55.133 0:0:0:0:0:ffff:8015:3785
128.21.55.134 0:0:0:0:0:ffff:8015:3786
128.21.55.135 0:0:0:0:0:ffff:8015:3787
128.21.55.136 0:0:0:0:0:ffff:8015:3788
128.21.55.137 0:0:0:0:0:ffff:8015:3789
128.21.55.138 0:0:0:0:0:ffff:8015:378a
128.21.55.139 0:0:0:0:0:ffff:8015:378b
128.21.55.140 0:0:0:0:0:ffff:8015:378c
128.21.55.141 0:0:0:0:0:ffff:8015:378d
128.21.55.142 0:0:0:0:0:ffff:8015:378e
128.21.55.143 0:0:0:0:0:ffff:8015:378f
128.21.55.144 0:0:0:0:0:ffff:8015:3790
128.21.55.145 0:0:0:0:0:ffff:8015:3791
128.21.55.146 0:0:0:0:0:ffff:8015:3792
128.21.55.147 0:0:0:0:0:ffff:8015:3793
128.21.55.148 0:0:0:0:0:ffff:8015:3794
128.21.55.149 0:0:0:0:0:ffff:8015:3795
128.21.55.150 0:0:0:0:0:ffff:8015:3796
128.21.55.151 0:0:0:0:0:ffff:8015:3797
128.21.55.152 0:0:0:0:0:ffff:8015:3798
128.21.55.153 0:0:0:0:0:ffff:8015:3799
128.21.55.154 0:0:0:0:0:ffff:8015:379a
128.21.55.155 0:0:0:0:0:ffff:8015:379b
128.21.55.156 0:0:0:0:0:ffff:8015:379c
128.21.55.157 0:0:0:0:0:ffff:8015:379d
128.21.55.158 0:0:0:0:0:ffff:8015:379e
128.21.55.159 0:0:0:0:0:ffff:8015:379f
128.21.55.160 0:0:0:0:0:ffff:8015:37a0
128.21.55.161 0:0:0:0:0:ffff:8015:37a1
128.21.55.162 0:0:0:0:0:ffff:8015:37a2
128.21.55.163 0:0:0:0:0:ffff:8015:37a3
128.21.55.164 0:0:0:0:0:ffff:8015:37a4
128.21.55.165 0:0:0:0:0:ffff:8015:37a5
128.21.55.166 0:0:0:0:0:ffff:8015:37a6
128.21.55.167 0:0:0:0:0:ffff:8015:37a7
128.21.55.168 0:0:0:0:0:ffff:8015:37a8
128.21.55.169 0:0:0:0:0:ffff:8015:37a9
128.21.55.170 0:0:0:0:0:ffff:8015:37aa
128.21.55.171 0:0:0:0:0:ffff:8015:37ab
128.21.55.172 0:0:0:0:0:ffff:8015:37ac
128.21.55.173 0:0:0:0:0:ffff:8015:37ad
128.21.55.174 0:0:0:0:0:ffff:8015:37ae
128.21.55.175 0:0:0:0:0:ffff:8015:37af
128.21.55.176 0:0:0:0:0:ffff:8015:37b0
128.21.55.177 0:0:0:0:0:ffff:8015:37b1
128.21.55.178 0:0:0:0:0:ffff:8015:37b2
128.21.55.179 0:0:0:0:0:ffff:8015:37b3
128.21.55.180 0:0:0:0:0:ffff:8015:37b4


128.21.55.181 0:0:0:0:0:ffff:8015:37b5
128.21.55.182 0:0:0:0:0:ffff:8015:37b6
128.21.55.183 0:0:0:0:0:ffff:8015:37b7
128.21.55.184 0:0:0:0:0:ffff:8015:37b8
128.21.55.185 0:0:0:0:0:ffff:8015:37b9
128.21.55.186 0:0:0:0:0:ffff:8015:37ba
128.21.55.187 0:0:0:0:0:ffff:8015:37bb
128.21.55.188 0:0:0:0:0:ffff:8015:37bc
128.21.55.189 0:0:0:0:0:ffff:8015:37bd
128.21.55.190 0:0:0:0:0:ffff:8015:37be
128.21.55.191 0:0:0:0:0:ffff:8015:37bf
128.21.55.192 0:0:0:0:0:ffff:8015:37c0
128.21.55.193 0:0:0:0:0:ffff:8015:37c1
128.21.55.194 0:0:0:0:0:ffff:8015:37c2
128.21.55.195 0:0:0:0:0:ffff:8015:37c3
128.21.55.196 0:0:0:0:0:ffff:8015:37c4
128.21.55.197 0:0:0:0:0:ffff:8015:37c5
128.21.55.198 0:0:0:0:0:ffff:8015:37c6
128.21.55.199 0:0:0:0:0:ffff:8015:37c7
128.21.55.200 0:0:0:0:0:ffff:8015:37c8
128.21.55.201 0:0:0:0:0:ffff:8015:37c9
128.21.55.202 0:0:0:0:0:ffff:8015:37ca
128.21.55.203 0:0:0:0:0:ffff:8015:37cb
128.21.55.204 0:0:0:0:0:ffff:8015:37cc
128.21.55.205 0:0:0:0:0:ffff:8015:37cd
128.21.55.206 0:0:0:0:0:ffff:8015:37ce
128.21.55.207 0:0:0:0:0:ffff:8015:37cf
128.21.55.208 0:0:0:0:0:ffff:8015:37d0
128.21.55.209 0:0:0:0:0:ffff:8015:37d1
128.21.55.210 0:0:0:0:0:ffff:8015:37d2
128.21.55.211 0:0:0:0:0:ffff:8015:37d3
128.21.55.212 0:0:0:0:0:ffff:8015:37d4
128.21.55.213 0:0:0:0:0:ffff:8015:37d5
128.21.55.214 0:0:0:0:0:ffff:8015:37d6
128.21.55.215 0:0:0:0:0:ffff:8015:37d7
128.21.55.216 0:0:0:0:0:ffff:8015:37d8
128.21.55.217 0:0:0:0:0:ffff:8015:37d9
128.21.55.218 0:0:0:0:0:ffff:8015:37da
128.21.55.219 0:0:0:0:0:ffff:8015:37db
128.21.55.220 0:0:0:0:0:ffff:8015:37dc
128.21.55.221 0:0:0:0:0:ffff:8015:37dd
128.21.55.222 0:0:0:0:0:ffff:8015:37de
128.21.55.223 0:0:0:0:0:ffff:8015:37df
128.21.55.224 0:0:0:0:0:ffff:8015:37e0
128.21.55.225 0:0:0:0:0:ffff:8015:37e1
128.21.55.226 0:0:0:0:0:ffff:8015:37e2
128.21.55.227 0:0:0:0:0:ffff:8015:37e3
128.21.55.228 0:0:0:0:0:ffff:8015:37e4
128.21.55.229 0:0:0:0:0:ffff:8015:37e5
128.21.55.230 0:0:0:0:0:ffff:8015:37e6
128.21.55.231 0:0:0:0:0:ffff:8015:37e7
128.21.55.232 0:0:0:0:0:ffff:8015:37e8
128.21.55.233 0:0:0:0:0:ffff:8015:37e9
128.21.55.234 0:0:0:0:0:ffff:8015:37ea
128.21.55.235 0:0:0:0:0:ffff:8015:37eb
128.21.55.236 0:0:0:0:0:ffff:8015:37ec
128.21.55.237 0:0:0:0:0:ffff:8015:37ed
128.21.55.238 0:0:0:0:0:ffff:8015:37ee
128.21.55.239 0:0:0:0:0:ffff:8015:37ef
128.21.55.240 0:0:0:0:0:ffff:8015:37f0
128.21.55.241 0:0:0:0:0:ffff:8015:37f1
128.21.55.242 0:0:0:0:0:ffff:8015:37f2
128.21.55.243 0:0:0:0:0:ffff:8015:37f3
128.21.55.244 0:0:0:0:0:ffff:8015:37f4
128.21.55.245 0:0:0:0:0:ffff:8015:37f5
128.21.55.246 0:0:0:0:0:ffff:8015:37f6
128.21.55.247 0:0:0:0:0:ffff:8015:37f7
128.21.55.248 0:0:0:0:0:ffff:8015:37f8
128.21.55.249 0:0:0:0:0:ffff:8015:37f9
128.21.55.250 0:0:0:0:0:ffff:8015:37fa
128.21.55.251 0:0:0:0:0:ffff:8015:37fb
128.21.55.252 0:0:0:0:0:ffff:8015:37fc
128.21.55.253 0:0:0:0:0:ffff:8015:37fd
128.21.55.254 0:0:0:0:0:ffff:8015:37fe
128.21.55.255 0:0:0:0:0:ffff:8015:37ff


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.