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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.

Network95.41.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
95.41.0.0
Broadcast address
95.41.127.255
First usable
95.41.0.1
Last usable
95.41.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 5F290000 · Integer 1596522496 to 1596555263
Reverse DNS zones
0.41.95.in-addr.arpa
1.41.95.in-addr.arpa
2.41.95.in-addr.arpa
3.41.95.in-addr.arpa
4.41.95.in-addr.arpa
5.41.95.in-addr.arpa
6.41.95.in-addr.arpa
7.41.95.in-addr.arpa
8.41.95.in-addr.arpa
9.41.95.in-addr.arpa
10.41.95.in-addr.arpa
11.41.95.in-addr.arpa
12.41.95.in-addr.arpa
13.41.95.in-addr.arpa
14.41.95.in-addr.arpa
15.41.95.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011111.00101001.00000000.0000000095.41.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network01011111.00101001.00000000.0000000095.41.0.0
Broadcast01011111.00101001.01111111.1111111195.41.127.255
Split into smaller subnets/25
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

95.41.0.0/17 makes 256 subnets of /25.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
195.41.0.0/2595.41.0.1 to 95.41.0.12695.41.0.127126
295.41.0.128/2595.41.0.129 to 95.41.0.25495.41.0.255126
395.41.1.0/2595.41.1.1 to 95.41.1.12695.41.1.127126
495.41.1.128/2595.41.1.129 to 95.41.1.25495.41.1.255126
595.41.2.0/2595.41.2.1 to 95.41.2.12695.41.2.127126
695.41.2.128/2595.41.2.129 to 95.41.2.25495.41.2.255126
795.41.3.0/2595.41.3.1 to 95.41.3.12695.41.3.127126
895.41.3.128/2595.41.3.129 to 95.41.3.25495.41.3.255126
995.41.4.0/2595.41.4.1 to 95.41.4.12695.41.4.127126
1095.41.4.128/2595.41.4.129 to 95.41.4.25495.41.4.255126
1195.41.5.0/2595.41.5.1 to 95.41.5.12695.41.5.127126
1295.41.5.128/2595.41.5.129 to 95.41.5.25495.41.5.255126
1395.41.6.0/2595.41.6.1 to 95.41.6.12695.41.6.127126
1495.41.6.128/2595.41.6.129 to 95.41.6.25495.41.6.255126
1595.41.7.0/2595.41.7.1 to 95.41.7.12695.41.7.127126
1695.41.7.128/2595.41.7.129 to 95.41.7.25495.41.7.255126
1795.41.8.0/2595.41.8.1 to 95.41.8.12695.41.8.127126
1895.41.8.128/2595.41.8.129 to 95.41.8.25495.41.8.255126
1995.41.9.0/2595.41.9.1 to 95.41.9.12695.41.9.127126
2095.41.9.128/2595.41.9.129 to 95.41.9.25495.41.9.255126
2195.41.10.0/2595.41.10.1 to 95.41.10.12695.41.10.127126
2295.41.10.128/2595.41.10.129 to 95.41.10.25495.41.10.255126
2395.41.11.0/2595.41.11.1 to 95.41.11.12695.41.11.127126
2495.41.11.128/2595.41.11.129 to 95.41.11.25495.41.11.255126
2595.41.12.0/2595.41.12.1 to 95.41.12.12695.41.12.127126
2695.41.12.128/2595.41.12.129 to 95.41.12.25495.41.12.255126
2795.41.13.0/2595.41.13.1 to 95.41.13.12695.41.13.127126
2895.41.13.128/2595.41.13.129 to 95.41.13.25495.41.13.255126
2995.41.14.0/2595.41.14.1 to 95.41.14.12695.41.14.127126
3095.41.14.128/2595.41.14.129 to 95.41.14.25495.41.14.255126
3195.41.15.0/2595.41.15.1 to 95.41.15.12695.41.15.127126
3295.41.15.128/2595.41.15.129 to 95.41.15.25495.41.15.255126
3395.41.16.0/2595.41.16.1 to 95.41.16.12695.41.16.127126
3495.41.16.128/2595.41.16.129 to 95.41.16.25495.41.16.255126
3595.41.17.0/2595.41.17.1 to 95.41.17.12695.41.17.127126
3695.41.17.128/2595.41.17.129 to 95.41.17.25495.41.17.255126
3795.41.18.0/2595.41.18.1 to 95.41.18.12695.41.18.127126
3895.41.18.128/2595.41.18.129 to 95.41.18.25495.41.18.255126
3995.41.19.0/2595.41.19.1 to 95.41.19.12695.41.19.127126
4095.41.19.128/2595.41.19.129 to 95.41.19.25495.41.19.255126
4195.41.20.0/2595.41.20.1 to 95.41.20.12695.41.20.127126
4295.41.20.128/2595.41.20.129 to 95.41.20.25495.41.20.255126
4395.41.21.0/2595.41.21.1 to 95.41.21.12695.41.21.127126
4495.41.21.128/2595.41.21.129 to 95.41.21.25495.41.21.255126
4595.41.22.0/2595.41.22.1 to 95.41.22.12695.41.22.127126
4695.41.22.128/2595.41.22.129 to 95.41.22.25495.41.22.255126
4795.41.23.0/2595.41.23.1 to 95.41.23.12695.41.23.127126
4895.41.23.128/2595.41.23.129 to 95.41.23.25495.41.23.255126
4995.41.24.0/2595.41.24.1 to 95.41.24.12695.41.24.127126
5095.41.24.128/2595.41.24.129 to 95.41.24.25495.41.24.255126
5195.41.25.0/2595.41.25.1 to 95.41.25.12695.41.25.127126
5295.41.25.128/2595.41.25.129 to 95.41.25.25495.41.25.255126
5395.41.26.0/2595.41.26.1 to 95.41.26.12695.41.26.127126
5495.41.26.128/2595.41.26.129 to 95.41.26.25495.41.26.255126
5595.41.27.0/2595.41.27.1 to 95.41.27.12695.41.27.127126
5695.41.27.128/2595.41.27.129 to 95.41.27.25495.41.27.255126
5795.41.28.0/2595.41.28.1 to 95.41.28.12695.41.28.127126
5895.41.28.128/2595.41.28.129 to 95.41.28.25495.41.28.255126
5995.41.29.0/2595.41.29.1 to 95.41.29.12695.41.29.127126
6095.41.29.128/2595.41.29.129 to 95.41.29.25495.41.29.255126
6195.41.30.0/2595.41.30.1 to 95.41.30.12695.41.30.127126
6295.41.30.128/2595.41.30.129 to 95.41.30.25495.41.30.255126
6395.41.31.0/2595.41.31.1 to 95.41.31.12695.41.31.127126
6495.41.31.128/2595.41.31.129 to 95.41.31.25495.41.31.255126
6595.41.32.0/2595.41.32.1 to 95.41.32.12695.41.32.127126
6695.41.32.128/2595.41.32.129 to 95.41.32.25495.41.32.255126
6795.41.33.0/2595.41.33.1 to 95.41.33.12695.41.33.127126
6895.41.33.128/2595.41.33.129 to 95.41.33.25495.41.33.255126
6995.41.34.0/2595.41.34.1 to 95.41.34.12695.41.34.127126
7095.41.34.128/2595.41.34.129 to 95.41.34.25495.41.34.255126
7195.41.35.0/2595.41.35.1 to 95.41.35.12695.41.35.127126
7295.41.35.128/2595.41.35.129 to 95.41.35.25495.41.35.255126
7395.41.36.0/2595.41.36.1 to 95.41.36.12695.41.36.127126
7495.41.36.128/2595.41.36.129 to 95.41.36.25495.41.36.255126
7595.41.37.0/2595.41.37.1 to 95.41.37.12695.41.37.127126
7695.41.37.128/2595.41.37.129 to 95.41.37.25495.41.37.255126
7795.41.38.0/2595.41.38.1 to 95.41.38.12695.41.38.127126
7895.41.38.128/2595.41.38.129 to 95.41.38.25495.41.38.255126
7995.41.39.0/2595.41.39.1 to 95.41.39.12695.41.39.127126
8095.41.39.128/2595.41.39.129 to 95.41.39.25495.41.39.255126
8195.41.40.0/2595.41.40.1 to 95.41.40.12695.41.40.127126
8295.41.40.128/2595.41.40.129 to 95.41.40.25495.41.40.255126
8395.41.41.0/2595.41.41.1 to 95.41.41.12695.41.41.127126
8495.41.41.128/2595.41.41.129 to 95.41.41.25495.41.41.255126
8595.41.42.0/2595.41.42.1 to 95.41.42.12695.41.42.127126
8695.41.42.128/2595.41.42.129 to 95.41.42.25495.41.42.255126
8795.41.43.0/2595.41.43.1 to 95.41.43.12695.41.43.127126
8895.41.43.128/2595.41.43.129 to 95.41.43.25495.41.43.255126
8995.41.44.0/2595.41.44.1 to 95.41.44.12695.41.44.127126
9095.41.44.128/2595.41.44.129 to 95.41.44.25495.41.44.255126
9195.41.45.0/2595.41.45.1 to 95.41.45.12695.41.45.127126
9295.41.45.128/2595.41.45.129 to 95.41.45.25495.41.45.255126
9395.41.46.0/2595.41.46.1 to 95.41.46.12695.41.46.127126
9495.41.46.128/2595.41.46.129 to 95.41.46.25495.41.46.255126
9595.41.47.0/2595.41.47.1 to 95.41.47.12695.41.47.127126
9695.41.47.128/2595.41.47.129 to 95.41.47.25495.41.47.255126
9795.41.48.0/2595.41.48.1 to 95.41.48.12695.41.48.127126
9895.41.48.128/2595.41.48.129 to 95.41.48.25495.41.48.255126
9995.41.49.0/2595.41.49.1 to 95.41.49.12695.41.49.127126
10095.41.49.128/2595.41.49.129 to 95.41.49.25495.41.49.255126
10195.41.50.0/2595.41.50.1 to 95.41.50.12695.41.50.127126
10295.41.50.128/2595.41.50.129 to 95.41.50.25495.41.50.255126
10395.41.51.0/2595.41.51.1 to 95.41.51.12695.41.51.127126
10495.41.51.128/2595.41.51.129 to 95.41.51.25495.41.51.255126
10595.41.52.0/2595.41.52.1 to 95.41.52.12695.41.52.127126
10695.41.52.128/2595.41.52.129 to 95.41.52.25495.41.52.255126
10795.41.53.0/2595.41.53.1 to 95.41.53.12695.41.53.127126
10895.41.53.128/2595.41.53.129 to 95.41.53.25495.41.53.255126
10995.41.54.0/2595.41.54.1 to 95.41.54.12695.41.54.127126
11095.41.54.128/2595.41.54.129 to 95.41.54.25495.41.54.255126
11195.41.55.0/2595.41.55.1 to 95.41.55.12695.41.55.127126
11295.41.55.128/2595.41.55.129 to 95.41.55.25495.41.55.255126
11395.41.56.0/2595.41.56.1 to 95.41.56.12695.41.56.127126
11495.41.56.128/2595.41.56.129 to 95.41.56.25495.41.56.255126
11595.41.57.0/2595.41.57.1 to 95.41.57.12695.41.57.127126
11695.41.57.128/2595.41.57.129 to 95.41.57.25495.41.57.255126
11795.41.58.0/2595.41.58.1 to 95.41.58.12695.41.58.127126
11895.41.58.128/2595.41.58.129 to 95.41.58.25495.41.58.255126
11995.41.59.0/2595.41.59.1 to 95.41.59.12695.41.59.127126
12095.41.59.128/2595.41.59.129 to 95.41.59.25495.41.59.255126
12195.41.60.0/2595.41.60.1 to 95.41.60.12695.41.60.127126
12295.41.60.128/2595.41.60.129 to 95.41.60.25495.41.60.255126
12395.41.61.0/2595.41.61.1 to 95.41.61.12695.41.61.127126
12495.41.61.128/2595.41.61.129 to 95.41.61.25495.41.61.255126
12595.41.62.0/2595.41.62.1 to 95.41.62.12695.41.62.127126
12695.41.62.128/2595.41.62.129 to 95.41.62.25495.41.62.255126
12795.41.63.0/2595.41.63.1 to 95.41.63.12695.41.63.127126
12895.41.63.128/2595.41.63.129 to 95.41.63.25495.41.63.255126
12995.41.64.0/2595.41.64.1 to 95.41.64.12695.41.64.127126
13095.41.64.128/2595.41.64.129 to 95.41.64.25495.41.64.255126
13195.41.65.0/2595.41.65.1 to 95.41.65.12695.41.65.127126
13295.41.65.128/2595.41.65.129 to 95.41.65.25495.41.65.255126
13395.41.66.0/2595.41.66.1 to 95.41.66.12695.41.66.127126
13495.41.66.128/2595.41.66.129 to 95.41.66.25495.41.66.255126
13595.41.67.0/2595.41.67.1 to 95.41.67.12695.41.67.127126
13695.41.67.128/2595.41.67.129 to 95.41.67.25495.41.67.255126
13795.41.68.0/2595.41.68.1 to 95.41.68.12695.41.68.127126
13895.41.68.128/2595.41.68.129 to 95.41.68.25495.41.68.255126
13995.41.69.0/2595.41.69.1 to 95.41.69.12695.41.69.127126
14095.41.69.128/2595.41.69.129 to 95.41.69.25495.41.69.255126
14195.41.70.0/2595.41.70.1 to 95.41.70.12695.41.70.127126
14295.41.70.128/2595.41.70.129 to 95.41.70.25495.41.70.255126
14395.41.71.0/2595.41.71.1 to 95.41.71.12695.41.71.127126
14495.41.71.128/2595.41.71.129 to 95.41.71.25495.41.71.255126
14595.41.72.0/2595.41.72.1 to 95.41.72.12695.41.72.127126
14695.41.72.128/2595.41.72.129 to 95.41.72.25495.41.72.255126
14795.41.73.0/2595.41.73.1 to 95.41.73.12695.41.73.127126
14895.41.73.128/2595.41.73.129 to 95.41.73.25495.41.73.255126
14995.41.74.0/2595.41.74.1 to 95.41.74.12695.41.74.127126
15095.41.74.128/2595.41.74.129 to 95.41.74.25495.41.74.255126
15195.41.75.0/2595.41.75.1 to 95.41.75.12695.41.75.127126
15295.41.75.128/2595.41.75.129 to 95.41.75.25495.41.75.255126
15395.41.76.0/2595.41.76.1 to 95.41.76.12695.41.76.127126
15495.41.76.128/2595.41.76.129 to 95.41.76.25495.41.76.255126
15595.41.77.0/2595.41.77.1 to 95.41.77.12695.41.77.127126
15695.41.77.128/2595.41.77.129 to 95.41.77.25495.41.77.255126
15795.41.78.0/2595.41.78.1 to 95.41.78.12695.41.78.127126
15895.41.78.128/2595.41.78.129 to 95.41.78.25495.41.78.255126
15995.41.79.0/2595.41.79.1 to 95.41.79.12695.41.79.127126
16095.41.79.128/2595.41.79.129 to 95.41.79.25495.41.79.255126
16195.41.80.0/2595.41.80.1 to 95.41.80.12695.41.80.127126
16295.41.80.128/2595.41.80.129 to 95.41.80.25495.41.80.255126
16395.41.81.0/2595.41.81.1 to 95.41.81.12695.41.81.127126
16495.41.81.128/2595.41.81.129 to 95.41.81.25495.41.81.255126
16595.41.82.0/2595.41.82.1 to 95.41.82.12695.41.82.127126
16695.41.82.128/2595.41.82.129 to 95.41.82.25495.41.82.255126
16795.41.83.0/2595.41.83.1 to 95.41.83.12695.41.83.127126
16895.41.83.128/2595.41.83.129 to 95.41.83.25495.41.83.255126
16995.41.84.0/2595.41.84.1 to 95.41.84.12695.41.84.127126
17095.41.84.128/2595.41.84.129 to 95.41.84.25495.41.84.255126
17195.41.85.0/2595.41.85.1 to 95.41.85.12695.41.85.127126
17295.41.85.128/2595.41.85.129 to 95.41.85.25495.41.85.255126
17395.41.86.0/2595.41.86.1 to 95.41.86.12695.41.86.127126
17495.41.86.128/2595.41.86.129 to 95.41.86.25495.41.86.255126
17595.41.87.0/2595.41.87.1 to 95.41.87.12695.41.87.127126
17695.41.87.128/2595.41.87.129 to 95.41.87.25495.41.87.255126
17795.41.88.0/2595.41.88.1 to 95.41.88.12695.41.88.127126
17895.41.88.128/2595.41.88.129 to 95.41.88.25495.41.88.255126
17995.41.89.0/2595.41.89.1 to 95.41.89.12695.41.89.127126
18095.41.89.128/2595.41.89.129 to 95.41.89.25495.41.89.255126
18195.41.90.0/2595.41.90.1 to 95.41.90.12695.41.90.127126
18295.41.90.128/2595.41.90.129 to 95.41.90.25495.41.90.255126
18395.41.91.0/2595.41.91.1 to 95.41.91.12695.41.91.127126
18495.41.91.128/2595.41.91.129 to 95.41.91.25495.41.91.255126
18595.41.92.0/2595.41.92.1 to 95.41.92.12695.41.92.127126
18695.41.92.128/2595.41.92.129 to 95.41.92.25495.41.92.255126
18795.41.93.0/2595.41.93.1 to 95.41.93.12695.41.93.127126
18895.41.93.128/2595.41.93.129 to 95.41.93.25495.41.93.255126
18995.41.94.0/2595.41.94.1 to 95.41.94.12695.41.94.127126
19095.41.94.128/2595.41.94.129 to 95.41.94.25495.41.94.255126
19195.41.95.0/2595.41.95.1 to 95.41.95.12695.41.95.127126
19295.41.95.128/2595.41.95.129 to 95.41.95.25495.41.95.255126
19395.41.96.0/2595.41.96.1 to 95.41.96.12695.41.96.127126
19495.41.96.128/2595.41.96.129 to 95.41.96.25495.41.96.255126
19595.41.97.0/2595.41.97.1 to 95.41.97.12695.41.97.127126
19695.41.97.128/2595.41.97.129 to 95.41.97.25495.41.97.255126
19795.41.98.0/2595.41.98.1 to 95.41.98.12695.41.98.127126
19895.41.98.128/2595.41.98.129 to 95.41.98.25495.41.98.255126
19995.41.99.0/2595.41.99.1 to 95.41.99.12695.41.99.127126
20095.41.99.128/2595.41.99.129 to 95.41.99.25495.41.99.255126
20195.41.100.0/2595.41.100.1 to 95.41.100.12695.41.100.127126
20295.41.100.128/2595.41.100.129 to 95.41.100.25495.41.100.255126
20395.41.101.0/2595.41.101.1 to 95.41.101.12695.41.101.127126
20495.41.101.128/2595.41.101.129 to 95.41.101.25495.41.101.255126
20595.41.102.0/2595.41.102.1 to 95.41.102.12695.41.102.127126
20695.41.102.128/2595.41.102.129 to 95.41.102.25495.41.102.255126
20795.41.103.0/2595.41.103.1 to 95.41.103.12695.41.103.127126
20895.41.103.128/2595.41.103.129 to 95.41.103.25495.41.103.255126
20995.41.104.0/2595.41.104.1 to 95.41.104.12695.41.104.127126
21095.41.104.128/2595.41.104.129 to 95.41.104.25495.41.104.255126
21195.41.105.0/2595.41.105.1 to 95.41.105.12695.41.105.127126
21295.41.105.128/2595.41.105.129 to 95.41.105.25495.41.105.255126
21395.41.106.0/2595.41.106.1 to 95.41.106.12695.41.106.127126
21495.41.106.128/2595.41.106.129 to 95.41.106.25495.41.106.255126
21595.41.107.0/2595.41.107.1 to 95.41.107.12695.41.107.127126
21695.41.107.128/2595.41.107.129 to 95.41.107.25495.41.107.255126
21795.41.108.0/2595.41.108.1 to 95.41.108.12695.41.108.127126
21895.41.108.128/2595.41.108.129 to 95.41.108.25495.41.108.255126
21995.41.109.0/2595.41.109.1 to 95.41.109.12695.41.109.127126
22095.41.109.128/2595.41.109.129 to 95.41.109.25495.41.109.255126
22195.41.110.0/2595.41.110.1 to 95.41.110.12695.41.110.127126
22295.41.110.128/2595.41.110.129 to 95.41.110.25495.41.110.255126
22395.41.111.0/2595.41.111.1 to 95.41.111.12695.41.111.127126
22495.41.111.128/2595.41.111.129 to 95.41.111.25495.41.111.255126
22595.41.112.0/2595.41.112.1 to 95.41.112.12695.41.112.127126
22695.41.112.128/2595.41.112.129 to 95.41.112.25495.41.112.255126
22795.41.113.0/2595.41.113.1 to 95.41.113.12695.41.113.127126
22895.41.113.128/2595.41.113.129 to 95.41.113.25495.41.113.255126
22995.41.114.0/2595.41.114.1 to 95.41.114.12695.41.114.127126
23095.41.114.128/2595.41.114.129 to 95.41.114.25495.41.114.255126
23195.41.115.0/2595.41.115.1 to 95.41.115.12695.41.115.127126
23295.41.115.128/2595.41.115.129 to 95.41.115.25495.41.115.255126
23395.41.116.0/2595.41.116.1 to 95.41.116.12695.41.116.127126
23495.41.116.128/2595.41.116.129 to 95.41.116.25495.41.116.255126
23595.41.117.0/2595.41.117.1 to 95.41.117.12695.41.117.127126
23695.41.117.128/2595.41.117.129 to 95.41.117.25495.41.117.255126
23795.41.118.0/2595.41.118.1 to 95.41.118.12695.41.118.127126
23895.41.118.128/2595.41.118.129 to 95.41.118.25495.41.118.255126
23995.41.119.0/2595.41.119.1 to 95.41.119.12695.41.119.127126
24095.41.119.128/2595.41.119.129 to 95.41.119.25495.41.119.255126
24195.41.120.0/2595.41.120.1 to 95.41.120.12695.41.120.127126
24295.41.120.128/2595.41.120.129 to 95.41.120.25495.41.120.255126
24395.41.121.0/2595.41.121.1 to 95.41.121.12695.41.121.127126
24495.41.121.128/2595.41.121.129 to 95.41.121.25495.41.121.255126
24595.41.122.0/2595.41.122.1 to 95.41.122.12695.41.122.127126
24695.41.122.128/2595.41.122.129 to 95.41.122.25495.41.122.255126
24795.41.123.0/2595.41.123.1 to 95.41.123.12695.41.123.127126
24895.41.123.128/2595.41.123.129 to 95.41.123.25495.41.123.255126
24995.41.124.0/2595.41.124.1 to 95.41.124.12695.41.124.127126
25095.41.124.128/2595.41.124.129 to 95.41.124.25495.41.124.255126
25195.41.125.0/2595.41.125.1 to 95.41.125.12695.41.125.127126
25295.41.125.128/2595.41.125.129 to 95.41.125.25495.41.125.255126
25395.41.126.0/2595.41.126.1 to 95.41.126.12695.41.126.127126
25495.41.126.128/2595.41.126.129 to 95.41.126.25495.41.126.255126
25595.41.127.0/2595.41.127.1 to 95.41.127.12695.41.127.127126
25695.41.127.128/2595.41.127.129 to 95.41.127.25495.41.127.255126

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.