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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.

Network95.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
95.0.0.0
Broadcast address
95.255.255.255
First usable
95.0.0.1
Last usable
95.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 5F000000 · Integer 1593835520 to 1610612735
Reverse DNS zone
95.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011111..00000000.00000000.0000000095.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01011111..00000000.00000000.0000000095.0.0.0
Broadcast01011111..11111111.11111111.1111111195.255.255.255
Split into smaller subnets/17
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

95.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
195.0.0.0/1795.0.0.1 to 95.0.127.25495.0.127.25532,766
295.0.128.0/1795.0.128.1 to 95.0.255.25495.0.255.25532,766
395.1.0.0/1795.1.0.1 to 95.1.127.25495.1.127.25532,766
495.1.128.0/1795.1.128.1 to 95.1.255.25495.1.255.25532,766
595.2.0.0/1795.2.0.1 to 95.2.127.25495.2.127.25532,766
695.2.128.0/1795.2.128.1 to 95.2.255.25495.2.255.25532,766
795.3.0.0/1795.3.0.1 to 95.3.127.25495.3.127.25532,766
895.3.128.0/1795.3.128.1 to 95.3.255.25495.3.255.25532,766
995.4.0.0/1795.4.0.1 to 95.4.127.25495.4.127.25532,766
1095.4.128.0/1795.4.128.1 to 95.4.255.25495.4.255.25532,766
1195.5.0.0/1795.5.0.1 to 95.5.127.25495.5.127.25532,766
1295.5.128.0/1795.5.128.1 to 95.5.255.25495.5.255.25532,766
1395.6.0.0/1795.6.0.1 to 95.6.127.25495.6.127.25532,766
1495.6.128.0/1795.6.128.1 to 95.6.255.25495.6.255.25532,766
1595.7.0.0/1795.7.0.1 to 95.7.127.25495.7.127.25532,766
1695.7.128.0/1795.7.128.1 to 95.7.255.25495.7.255.25532,766
1795.8.0.0/1795.8.0.1 to 95.8.127.25495.8.127.25532,766
1895.8.128.0/1795.8.128.1 to 95.8.255.25495.8.255.25532,766
1995.9.0.0/1795.9.0.1 to 95.9.127.25495.9.127.25532,766
2095.9.128.0/1795.9.128.1 to 95.9.255.25495.9.255.25532,766
2195.10.0.0/1795.10.0.1 to 95.10.127.25495.10.127.25532,766
2295.10.128.0/1795.10.128.1 to 95.10.255.25495.10.255.25532,766
2395.11.0.0/1795.11.0.1 to 95.11.127.25495.11.127.25532,766
2495.11.128.0/1795.11.128.1 to 95.11.255.25495.11.255.25532,766
2595.12.0.0/1795.12.0.1 to 95.12.127.25495.12.127.25532,766
2695.12.128.0/1795.12.128.1 to 95.12.255.25495.12.255.25532,766
2795.13.0.0/1795.13.0.1 to 95.13.127.25495.13.127.25532,766
2895.13.128.0/1795.13.128.1 to 95.13.255.25495.13.255.25532,766
2995.14.0.0/1795.14.0.1 to 95.14.127.25495.14.127.25532,766
3095.14.128.0/1795.14.128.1 to 95.14.255.25495.14.255.25532,766
3195.15.0.0/1795.15.0.1 to 95.15.127.25495.15.127.25532,766
3295.15.128.0/1795.15.128.1 to 95.15.255.25495.15.255.25532,766
3395.16.0.0/1795.16.0.1 to 95.16.127.25495.16.127.25532,766
3495.16.128.0/1795.16.128.1 to 95.16.255.25495.16.255.25532,766
3595.17.0.0/1795.17.0.1 to 95.17.127.25495.17.127.25532,766
3695.17.128.0/1795.17.128.1 to 95.17.255.25495.17.255.25532,766
3795.18.0.0/1795.18.0.1 to 95.18.127.25495.18.127.25532,766
3895.18.128.0/1795.18.128.1 to 95.18.255.25495.18.255.25532,766
3995.19.0.0/1795.19.0.1 to 95.19.127.25495.19.127.25532,766
4095.19.128.0/1795.19.128.1 to 95.19.255.25495.19.255.25532,766
4195.20.0.0/1795.20.0.1 to 95.20.127.25495.20.127.25532,766
4295.20.128.0/1795.20.128.1 to 95.20.255.25495.20.255.25532,766
4395.21.0.0/1795.21.0.1 to 95.21.127.25495.21.127.25532,766
4495.21.128.0/1795.21.128.1 to 95.21.255.25495.21.255.25532,766
4595.22.0.0/1795.22.0.1 to 95.22.127.25495.22.127.25532,766
4695.22.128.0/1795.22.128.1 to 95.22.255.25495.22.255.25532,766
4795.23.0.0/1795.23.0.1 to 95.23.127.25495.23.127.25532,766
4895.23.128.0/1795.23.128.1 to 95.23.255.25495.23.255.25532,766
4995.24.0.0/1795.24.0.1 to 95.24.127.25495.24.127.25532,766
5095.24.128.0/1795.24.128.1 to 95.24.255.25495.24.255.25532,766
5195.25.0.0/1795.25.0.1 to 95.25.127.25495.25.127.25532,766
5295.25.128.0/1795.25.128.1 to 95.25.255.25495.25.255.25532,766
5395.26.0.0/1795.26.0.1 to 95.26.127.25495.26.127.25532,766
5495.26.128.0/1795.26.128.1 to 95.26.255.25495.26.255.25532,766
5595.27.0.0/1795.27.0.1 to 95.27.127.25495.27.127.25532,766
5695.27.128.0/1795.27.128.1 to 95.27.255.25495.27.255.25532,766
5795.28.0.0/1795.28.0.1 to 95.28.127.25495.28.127.25532,766
5895.28.128.0/1795.28.128.1 to 95.28.255.25495.28.255.25532,766
5995.29.0.0/1795.29.0.1 to 95.29.127.25495.29.127.25532,766
6095.29.128.0/1795.29.128.1 to 95.29.255.25495.29.255.25532,766
6195.30.0.0/1795.30.0.1 to 95.30.127.25495.30.127.25532,766
6295.30.128.0/1795.30.128.1 to 95.30.255.25495.30.255.25532,766
6395.31.0.0/1795.31.0.1 to 95.31.127.25495.31.127.25532,766
6495.31.128.0/1795.31.128.1 to 95.31.255.25495.31.255.25532,766
6595.32.0.0/1795.32.0.1 to 95.32.127.25495.32.127.25532,766
6695.32.128.0/1795.32.128.1 to 95.32.255.25495.32.255.25532,766
6795.33.0.0/1795.33.0.1 to 95.33.127.25495.33.127.25532,766
6895.33.128.0/1795.33.128.1 to 95.33.255.25495.33.255.25532,766
6995.34.0.0/1795.34.0.1 to 95.34.127.25495.34.127.25532,766
7095.34.128.0/1795.34.128.1 to 95.34.255.25495.34.255.25532,766
7195.35.0.0/1795.35.0.1 to 95.35.127.25495.35.127.25532,766
7295.35.128.0/1795.35.128.1 to 95.35.255.25495.35.255.25532,766
7395.36.0.0/1795.36.0.1 to 95.36.127.25495.36.127.25532,766
7495.36.128.0/1795.36.128.1 to 95.36.255.25495.36.255.25532,766
7595.37.0.0/1795.37.0.1 to 95.37.127.25495.37.127.25532,766
7695.37.128.0/1795.37.128.1 to 95.37.255.25495.37.255.25532,766
7795.38.0.0/1795.38.0.1 to 95.38.127.25495.38.127.25532,766
7895.38.128.0/1795.38.128.1 to 95.38.255.25495.38.255.25532,766
7995.39.0.0/1795.39.0.1 to 95.39.127.25495.39.127.25532,766
8095.39.128.0/1795.39.128.1 to 95.39.255.25495.39.255.25532,766
8195.40.0.0/1795.40.0.1 to 95.40.127.25495.40.127.25532,766
8295.40.128.0/1795.40.128.1 to 95.40.255.25495.40.255.25532,766
8395.41.0.0/1795.41.0.1 to 95.41.127.25495.41.127.25532,766
8495.41.128.0/1795.41.128.1 to 95.41.255.25495.41.255.25532,766
8595.42.0.0/1795.42.0.1 to 95.42.127.25495.42.127.25532,766
8695.42.128.0/1795.42.128.1 to 95.42.255.25495.42.255.25532,766
8795.43.0.0/1795.43.0.1 to 95.43.127.25495.43.127.25532,766
8895.43.128.0/1795.43.128.1 to 95.43.255.25495.43.255.25532,766
8995.44.0.0/1795.44.0.1 to 95.44.127.25495.44.127.25532,766
9095.44.128.0/1795.44.128.1 to 95.44.255.25495.44.255.25532,766
9195.45.0.0/1795.45.0.1 to 95.45.127.25495.45.127.25532,766
9295.45.128.0/1795.45.128.1 to 95.45.255.25495.45.255.25532,766
9395.46.0.0/1795.46.0.1 to 95.46.127.25495.46.127.25532,766
9495.46.128.0/1795.46.128.1 to 95.46.255.25495.46.255.25532,766
9595.47.0.0/1795.47.0.1 to 95.47.127.25495.47.127.25532,766
9695.47.128.0/1795.47.128.1 to 95.47.255.25495.47.255.25532,766
9795.48.0.0/1795.48.0.1 to 95.48.127.25495.48.127.25532,766
9895.48.128.0/1795.48.128.1 to 95.48.255.25495.48.255.25532,766
9995.49.0.0/1795.49.0.1 to 95.49.127.25495.49.127.25532,766
10095.49.128.0/1795.49.128.1 to 95.49.255.25495.49.255.25532,766
10195.50.0.0/1795.50.0.1 to 95.50.127.25495.50.127.25532,766
10295.50.128.0/1795.50.128.1 to 95.50.255.25495.50.255.25532,766
10395.51.0.0/1795.51.0.1 to 95.51.127.25495.51.127.25532,766
10495.51.128.0/1795.51.128.1 to 95.51.255.25495.51.255.25532,766
10595.52.0.0/1795.52.0.1 to 95.52.127.25495.52.127.25532,766
10695.52.128.0/1795.52.128.1 to 95.52.255.25495.52.255.25532,766
10795.53.0.0/1795.53.0.1 to 95.53.127.25495.53.127.25532,766
10895.53.128.0/1795.53.128.1 to 95.53.255.25495.53.255.25532,766
10995.54.0.0/1795.54.0.1 to 95.54.127.25495.54.127.25532,766
11095.54.128.0/1795.54.128.1 to 95.54.255.25495.54.255.25532,766
11195.55.0.0/1795.55.0.1 to 95.55.127.25495.55.127.25532,766
11295.55.128.0/1795.55.128.1 to 95.55.255.25495.55.255.25532,766
11395.56.0.0/1795.56.0.1 to 95.56.127.25495.56.127.25532,766
11495.56.128.0/1795.56.128.1 to 95.56.255.25495.56.255.25532,766
11595.57.0.0/1795.57.0.1 to 95.57.127.25495.57.127.25532,766
11695.57.128.0/1795.57.128.1 to 95.57.255.25495.57.255.25532,766
11795.58.0.0/1795.58.0.1 to 95.58.127.25495.58.127.25532,766
11895.58.128.0/1795.58.128.1 to 95.58.255.25495.58.255.25532,766
11995.59.0.0/1795.59.0.1 to 95.59.127.25495.59.127.25532,766
12095.59.128.0/1795.59.128.1 to 95.59.255.25495.59.255.25532,766
12195.60.0.0/1795.60.0.1 to 95.60.127.25495.60.127.25532,766
12295.60.128.0/1795.60.128.1 to 95.60.255.25495.60.255.25532,766
12395.61.0.0/1795.61.0.1 to 95.61.127.25495.61.127.25532,766
12495.61.128.0/1795.61.128.1 to 95.61.255.25495.61.255.25532,766
12595.62.0.0/1795.62.0.1 to 95.62.127.25495.62.127.25532,766
12695.62.128.0/1795.62.128.1 to 95.62.255.25495.62.255.25532,766
12795.63.0.0/1795.63.0.1 to 95.63.127.25495.63.127.25532,766
12895.63.128.0/1795.63.128.1 to 95.63.255.25495.63.255.25532,766
12995.64.0.0/1795.64.0.1 to 95.64.127.25495.64.127.25532,766
13095.64.128.0/1795.64.128.1 to 95.64.255.25495.64.255.25532,766
13195.65.0.0/1795.65.0.1 to 95.65.127.25495.65.127.25532,766
13295.65.128.0/1795.65.128.1 to 95.65.255.25495.65.255.25532,766
13395.66.0.0/1795.66.0.1 to 95.66.127.25495.66.127.25532,766
13495.66.128.0/1795.66.128.1 to 95.66.255.25495.66.255.25532,766
13595.67.0.0/1795.67.0.1 to 95.67.127.25495.67.127.25532,766
13695.67.128.0/1795.67.128.1 to 95.67.255.25495.67.255.25532,766
13795.68.0.0/1795.68.0.1 to 95.68.127.25495.68.127.25532,766
13895.68.128.0/1795.68.128.1 to 95.68.255.25495.68.255.25532,766
13995.69.0.0/1795.69.0.1 to 95.69.127.25495.69.127.25532,766
14095.69.128.0/1795.69.128.1 to 95.69.255.25495.69.255.25532,766
14195.70.0.0/1795.70.0.1 to 95.70.127.25495.70.127.25532,766
14295.70.128.0/1795.70.128.1 to 95.70.255.25495.70.255.25532,766
14395.71.0.0/1795.71.0.1 to 95.71.127.25495.71.127.25532,766
14495.71.128.0/1795.71.128.1 to 95.71.255.25495.71.255.25532,766
14595.72.0.0/1795.72.0.1 to 95.72.127.25495.72.127.25532,766
14695.72.128.0/1795.72.128.1 to 95.72.255.25495.72.255.25532,766
14795.73.0.0/1795.73.0.1 to 95.73.127.25495.73.127.25532,766
14895.73.128.0/1795.73.128.1 to 95.73.255.25495.73.255.25532,766
14995.74.0.0/1795.74.0.1 to 95.74.127.25495.74.127.25532,766
15095.74.128.0/1795.74.128.1 to 95.74.255.25495.74.255.25532,766
15195.75.0.0/1795.75.0.1 to 95.75.127.25495.75.127.25532,766
15295.75.128.0/1795.75.128.1 to 95.75.255.25495.75.255.25532,766
15395.76.0.0/1795.76.0.1 to 95.76.127.25495.76.127.25532,766
15495.76.128.0/1795.76.128.1 to 95.76.255.25495.76.255.25532,766
15595.77.0.0/1795.77.0.1 to 95.77.127.25495.77.127.25532,766
15695.77.128.0/1795.77.128.1 to 95.77.255.25495.77.255.25532,766
15795.78.0.0/1795.78.0.1 to 95.78.127.25495.78.127.25532,766
15895.78.128.0/1795.78.128.1 to 95.78.255.25495.78.255.25532,766
15995.79.0.0/1795.79.0.1 to 95.79.127.25495.79.127.25532,766
16095.79.128.0/1795.79.128.1 to 95.79.255.25495.79.255.25532,766
16195.80.0.0/1795.80.0.1 to 95.80.127.25495.80.127.25532,766
16295.80.128.0/1795.80.128.1 to 95.80.255.25495.80.255.25532,766
16395.81.0.0/1795.81.0.1 to 95.81.127.25495.81.127.25532,766
16495.81.128.0/1795.81.128.1 to 95.81.255.25495.81.255.25532,766
16595.82.0.0/1795.82.0.1 to 95.82.127.25495.82.127.25532,766
16695.82.128.0/1795.82.128.1 to 95.82.255.25495.82.255.25532,766
16795.83.0.0/1795.83.0.1 to 95.83.127.25495.83.127.25532,766
16895.83.128.0/1795.83.128.1 to 95.83.255.25495.83.255.25532,766
16995.84.0.0/1795.84.0.1 to 95.84.127.25495.84.127.25532,766
17095.84.128.0/1795.84.128.1 to 95.84.255.25495.84.255.25532,766
17195.85.0.0/1795.85.0.1 to 95.85.127.25495.85.127.25532,766
17295.85.128.0/1795.85.128.1 to 95.85.255.25495.85.255.25532,766
17395.86.0.0/1795.86.0.1 to 95.86.127.25495.86.127.25532,766
17495.86.128.0/1795.86.128.1 to 95.86.255.25495.86.255.25532,766
17595.87.0.0/1795.87.0.1 to 95.87.127.25495.87.127.25532,766
17695.87.128.0/1795.87.128.1 to 95.87.255.25495.87.255.25532,766
17795.88.0.0/1795.88.0.1 to 95.88.127.25495.88.127.25532,766
17895.88.128.0/1795.88.128.1 to 95.88.255.25495.88.255.25532,766
17995.89.0.0/1795.89.0.1 to 95.89.127.25495.89.127.25532,766
18095.89.128.0/1795.89.128.1 to 95.89.255.25495.89.255.25532,766
18195.90.0.0/1795.90.0.1 to 95.90.127.25495.90.127.25532,766
18295.90.128.0/1795.90.128.1 to 95.90.255.25495.90.255.25532,766
18395.91.0.0/1795.91.0.1 to 95.91.127.25495.91.127.25532,766
18495.91.128.0/1795.91.128.1 to 95.91.255.25495.91.255.25532,766
18595.92.0.0/1795.92.0.1 to 95.92.127.25495.92.127.25532,766
18695.92.128.0/1795.92.128.1 to 95.92.255.25495.92.255.25532,766
18795.93.0.0/1795.93.0.1 to 95.93.127.25495.93.127.25532,766
18895.93.128.0/1795.93.128.1 to 95.93.255.25495.93.255.25532,766
18995.94.0.0/1795.94.0.1 to 95.94.127.25495.94.127.25532,766
19095.94.128.0/1795.94.128.1 to 95.94.255.25495.94.255.25532,766
19195.95.0.0/1795.95.0.1 to 95.95.127.25495.95.127.25532,766
19295.95.128.0/1795.95.128.1 to 95.95.255.25495.95.255.25532,766
19395.96.0.0/1795.96.0.1 to 95.96.127.25495.96.127.25532,766
19495.96.128.0/1795.96.128.1 to 95.96.255.25495.96.255.25532,766
19595.97.0.0/1795.97.0.1 to 95.97.127.25495.97.127.25532,766
19695.97.128.0/1795.97.128.1 to 95.97.255.25495.97.255.25532,766
19795.98.0.0/1795.98.0.1 to 95.98.127.25495.98.127.25532,766
19895.98.128.0/1795.98.128.1 to 95.98.255.25495.98.255.25532,766
19995.99.0.0/1795.99.0.1 to 95.99.127.25495.99.127.25532,766
20095.99.128.0/1795.99.128.1 to 95.99.255.25495.99.255.25532,766
20195.100.0.0/1795.100.0.1 to 95.100.127.25495.100.127.25532,766
20295.100.128.0/1795.100.128.1 to 95.100.255.25495.100.255.25532,766
20395.101.0.0/1795.101.0.1 to 95.101.127.25495.101.127.25532,766
20495.101.128.0/1795.101.128.1 to 95.101.255.25495.101.255.25532,766
20595.102.0.0/1795.102.0.1 to 95.102.127.25495.102.127.25532,766
20695.102.128.0/1795.102.128.1 to 95.102.255.25495.102.255.25532,766
20795.103.0.0/1795.103.0.1 to 95.103.127.25495.103.127.25532,766
20895.103.128.0/1795.103.128.1 to 95.103.255.25495.103.255.25532,766
20995.104.0.0/1795.104.0.1 to 95.104.127.25495.104.127.25532,766
21095.104.128.0/1795.104.128.1 to 95.104.255.25495.104.255.25532,766
21195.105.0.0/1795.105.0.1 to 95.105.127.25495.105.127.25532,766
21295.105.128.0/1795.105.128.1 to 95.105.255.25495.105.255.25532,766
21395.106.0.0/1795.106.0.1 to 95.106.127.25495.106.127.25532,766
21495.106.128.0/1795.106.128.1 to 95.106.255.25495.106.255.25532,766
21595.107.0.0/1795.107.0.1 to 95.107.127.25495.107.127.25532,766
21695.107.128.0/1795.107.128.1 to 95.107.255.25495.107.255.25532,766
21795.108.0.0/1795.108.0.1 to 95.108.127.25495.108.127.25532,766
21895.108.128.0/1795.108.128.1 to 95.108.255.25495.108.255.25532,766
21995.109.0.0/1795.109.0.1 to 95.109.127.25495.109.127.25532,766
22095.109.128.0/1795.109.128.1 to 95.109.255.25495.109.255.25532,766
22195.110.0.0/1795.110.0.1 to 95.110.127.25495.110.127.25532,766
22295.110.128.0/1795.110.128.1 to 95.110.255.25495.110.255.25532,766
22395.111.0.0/1795.111.0.1 to 95.111.127.25495.111.127.25532,766
22495.111.128.0/1795.111.128.1 to 95.111.255.25495.111.255.25532,766
22595.112.0.0/1795.112.0.1 to 95.112.127.25495.112.127.25532,766
22695.112.128.0/1795.112.128.1 to 95.112.255.25495.112.255.25532,766
22795.113.0.0/1795.113.0.1 to 95.113.127.25495.113.127.25532,766
22895.113.128.0/1795.113.128.1 to 95.113.255.25495.113.255.25532,766
22995.114.0.0/1795.114.0.1 to 95.114.127.25495.114.127.25532,766
23095.114.128.0/1795.114.128.1 to 95.114.255.25495.114.255.25532,766
23195.115.0.0/1795.115.0.1 to 95.115.127.25495.115.127.25532,766
23295.115.128.0/1795.115.128.1 to 95.115.255.25495.115.255.25532,766
23395.116.0.0/1795.116.0.1 to 95.116.127.25495.116.127.25532,766
23495.116.128.0/1795.116.128.1 to 95.116.255.25495.116.255.25532,766
23595.117.0.0/1795.117.0.1 to 95.117.127.25495.117.127.25532,766
23695.117.128.0/1795.117.128.1 to 95.117.255.25495.117.255.25532,766
23795.118.0.0/1795.118.0.1 to 95.118.127.25495.118.127.25532,766
23895.118.128.0/1795.118.128.1 to 95.118.255.25495.118.255.25532,766
23995.119.0.0/1795.119.0.1 to 95.119.127.25495.119.127.25532,766
24095.119.128.0/1795.119.128.1 to 95.119.255.25495.119.255.25532,766
24195.120.0.0/1795.120.0.1 to 95.120.127.25495.120.127.25532,766
24295.120.128.0/1795.120.128.1 to 95.120.255.25495.120.255.25532,766
24395.121.0.0/1795.121.0.1 to 95.121.127.25495.121.127.25532,766
24495.121.128.0/1795.121.128.1 to 95.121.255.25495.121.255.25532,766
24595.122.0.0/1795.122.0.1 to 95.122.127.25495.122.127.25532,766
24695.122.128.0/1795.122.128.1 to 95.122.255.25495.122.255.25532,766
24795.123.0.0/1795.123.0.1 to 95.123.127.25495.123.127.25532,766
24895.123.128.0/1795.123.128.1 to 95.123.255.25495.123.255.25532,766
24995.124.0.0/1795.124.0.1 to 95.124.127.25495.124.127.25532,766
25095.124.128.0/1795.124.128.1 to 95.124.255.25495.124.255.25532,766
25195.125.0.0/1795.125.0.1 to 95.125.127.25495.125.127.25532,766
25295.125.128.0/1795.125.128.1 to 95.125.255.25495.125.255.25532,766
25395.126.0.0/1795.126.0.1 to 95.126.127.25495.126.127.25532,766
25495.126.128.0/1795.126.128.1 to 95.126.255.25495.126.255.25532,766
25595.127.0.0/1795.127.0.1 to 95.127.127.25495.127.127.25532,766
25695.127.128.0/1795.127.128.1 to 95.127.255.25495.127.255.25532,766

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.