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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.

Network47.53.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
47.53.0.0
Broadcast address
47.53.127.255
First usable
47.53.0.1
Last usable
47.53.127.254
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 2F350000 · Integer 792002560 to 792035327
Reverse DNS zones
0.53.47.in-addr.arpa
1.53.47.in-addr.arpa
2.53.47.in-addr.arpa
3.53.47.in-addr.arpa
4.53.47.in-addr.arpa
5.53.47.in-addr.arpa
6.53.47.in-addr.arpa
7.53.47.in-addr.arpa
8.53.47.in-addr.arpa
9.53.47.in-addr.arpa
10.53.47.in-addr.arpa
11.53.47.in-addr.arpa
12.53.47.in-addr.arpa
13.53.47.in-addr.arpa
14.53.47.in-addr.arpa
15.53.47.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
Address00101111.00110101.00000000.0000000047.53.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00101111.00110101.00000000.0000000047.53.0.0
Broadcast00101111.00110101.01111111.1111111147.53.127.255
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)

47.53.0.0/17 makes 256 subnets of /25.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.53.0.0/2547.53.0.1 to 47.53.0.12647.53.0.127126
247.53.0.128/2547.53.0.129 to 47.53.0.25447.53.0.255126
347.53.1.0/2547.53.1.1 to 47.53.1.12647.53.1.127126
447.53.1.128/2547.53.1.129 to 47.53.1.25447.53.1.255126
547.53.2.0/2547.53.2.1 to 47.53.2.12647.53.2.127126
647.53.2.128/2547.53.2.129 to 47.53.2.25447.53.2.255126
747.53.3.0/2547.53.3.1 to 47.53.3.12647.53.3.127126
847.53.3.128/2547.53.3.129 to 47.53.3.25447.53.3.255126
947.53.4.0/2547.53.4.1 to 47.53.4.12647.53.4.127126
1047.53.4.128/2547.53.4.129 to 47.53.4.25447.53.4.255126
1147.53.5.0/2547.53.5.1 to 47.53.5.12647.53.5.127126
1247.53.5.128/2547.53.5.129 to 47.53.5.25447.53.5.255126
1347.53.6.0/2547.53.6.1 to 47.53.6.12647.53.6.127126
1447.53.6.128/2547.53.6.129 to 47.53.6.25447.53.6.255126
1547.53.7.0/2547.53.7.1 to 47.53.7.12647.53.7.127126
1647.53.7.128/2547.53.7.129 to 47.53.7.25447.53.7.255126
1747.53.8.0/2547.53.8.1 to 47.53.8.12647.53.8.127126
1847.53.8.128/2547.53.8.129 to 47.53.8.25447.53.8.255126
1947.53.9.0/2547.53.9.1 to 47.53.9.12647.53.9.127126
2047.53.9.128/2547.53.9.129 to 47.53.9.25447.53.9.255126
2147.53.10.0/2547.53.10.1 to 47.53.10.12647.53.10.127126
2247.53.10.128/2547.53.10.129 to 47.53.10.25447.53.10.255126
2347.53.11.0/2547.53.11.1 to 47.53.11.12647.53.11.127126
2447.53.11.128/2547.53.11.129 to 47.53.11.25447.53.11.255126
2547.53.12.0/2547.53.12.1 to 47.53.12.12647.53.12.127126
2647.53.12.128/2547.53.12.129 to 47.53.12.25447.53.12.255126
2747.53.13.0/2547.53.13.1 to 47.53.13.12647.53.13.127126
2847.53.13.128/2547.53.13.129 to 47.53.13.25447.53.13.255126
2947.53.14.0/2547.53.14.1 to 47.53.14.12647.53.14.127126
3047.53.14.128/2547.53.14.129 to 47.53.14.25447.53.14.255126
3147.53.15.0/2547.53.15.1 to 47.53.15.12647.53.15.127126
3247.53.15.128/2547.53.15.129 to 47.53.15.25447.53.15.255126
3347.53.16.0/2547.53.16.1 to 47.53.16.12647.53.16.127126
3447.53.16.128/2547.53.16.129 to 47.53.16.25447.53.16.255126
3547.53.17.0/2547.53.17.1 to 47.53.17.12647.53.17.127126
3647.53.17.128/2547.53.17.129 to 47.53.17.25447.53.17.255126
3747.53.18.0/2547.53.18.1 to 47.53.18.12647.53.18.127126
3847.53.18.128/2547.53.18.129 to 47.53.18.25447.53.18.255126
3947.53.19.0/2547.53.19.1 to 47.53.19.12647.53.19.127126
4047.53.19.128/2547.53.19.129 to 47.53.19.25447.53.19.255126
4147.53.20.0/2547.53.20.1 to 47.53.20.12647.53.20.127126
4247.53.20.128/2547.53.20.129 to 47.53.20.25447.53.20.255126
4347.53.21.0/2547.53.21.1 to 47.53.21.12647.53.21.127126
4447.53.21.128/2547.53.21.129 to 47.53.21.25447.53.21.255126
4547.53.22.0/2547.53.22.1 to 47.53.22.12647.53.22.127126
4647.53.22.128/2547.53.22.129 to 47.53.22.25447.53.22.255126
4747.53.23.0/2547.53.23.1 to 47.53.23.12647.53.23.127126
4847.53.23.128/2547.53.23.129 to 47.53.23.25447.53.23.255126
4947.53.24.0/2547.53.24.1 to 47.53.24.12647.53.24.127126
5047.53.24.128/2547.53.24.129 to 47.53.24.25447.53.24.255126
5147.53.25.0/2547.53.25.1 to 47.53.25.12647.53.25.127126
5247.53.25.128/2547.53.25.129 to 47.53.25.25447.53.25.255126
5347.53.26.0/2547.53.26.1 to 47.53.26.12647.53.26.127126
5447.53.26.128/2547.53.26.129 to 47.53.26.25447.53.26.255126
5547.53.27.0/2547.53.27.1 to 47.53.27.12647.53.27.127126
5647.53.27.128/2547.53.27.129 to 47.53.27.25447.53.27.255126
5747.53.28.0/2547.53.28.1 to 47.53.28.12647.53.28.127126
5847.53.28.128/2547.53.28.129 to 47.53.28.25447.53.28.255126
5947.53.29.0/2547.53.29.1 to 47.53.29.12647.53.29.127126
6047.53.29.128/2547.53.29.129 to 47.53.29.25447.53.29.255126
6147.53.30.0/2547.53.30.1 to 47.53.30.12647.53.30.127126
6247.53.30.128/2547.53.30.129 to 47.53.30.25447.53.30.255126
6347.53.31.0/2547.53.31.1 to 47.53.31.12647.53.31.127126
6447.53.31.128/2547.53.31.129 to 47.53.31.25447.53.31.255126
6547.53.32.0/2547.53.32.1 to 47.53.32.12647.53.32.127126
6647.53.32.128/2547.53.32.129 to 47.53.32.25447.53.32.255126
6747.53.33.0/2547.53.33.1 to 47.53.33.12647.53.33.127126
6847.53.33.128/2547.53.33.129 to 47.53.33.25447.53.33.255126
6947.53.34.0/2547.53.34.1 to 47.53.34.12647.53.34.127126
7047.53.34.128/2547.53.34.129 to 47.53.34.25447.53.34.255126
7147.53.35.0/2547.53.35.1 to 47.53.35.12647.53.35.127126
7247.53.35.128/2547.53.35.129 to 47.53.35.25447.53.35.255126
7347.53.36.0/2547.53.36.1 to 47.53.36.12647.53.36.127126
7447.53.36.128/2547.53.36.129 to 47.53.36.25447.53.36.255126
7547.53.37.0/2547.53.37.1 to 47.53.37.12647.53.37.127126
7647.53.37.128/2547.53.37.129 to 47.53.37.25447.53.37.255126
7747.53.38.0/2547.53.38.1 to 47.53.38.12647.53.38.127126
7847.53.38.128/2547.53.38.129 to 47.53.38.25447.53.38.255126
7947.53.39.0/2547.53.39.1 to 47.53.39.12647.53.39.127126
8047.53.39.128/2547.53.39.129 to 47.53.39.25447.53.39.255126
8147.53.40.0/2547.53.40.1 to 47.53.40.12647.53.40.127126
8247.53.40.128/2547.53.40.129 to 47.53.40.25447.53.40.255126
8347.53.41.0/2547.53.41.1 to 47.53.41.12647.53.41.127126
8447.53.41.128/2547.53.41.129 to 47.53.41.25447.53.41.255126
8547.53.42.0/2547.53.42.1 to 47.53.42.12647.53.42.127126
8647.53.42.128/2547.53.42.129 to 47.53.42.25447.53.42.255126
8747.53.43.0/2547.53.43.1 to 47.53.43.12647.53.43.127126
8847.53.43.128/2547.53.43.129 to 47.53.43.25447.53.43.255126
8947.53.44.0/2547.53.44.1 to 47.53.44.12647.53.44.127126
9047.53.44.128/2547.53.44.129 to 47.53.44.25447.53.44.255126
9147.53.45.0/2547.53.45.1 to 47.53.45.12647.53.45.127126
9247.53.45.128/2547.53.45.129 to 47.53.45.25447.53.45.255126
9347.53.46.0/2547.53.46.1 to 47.53.46.12647.53.46.127126
9447.53.46.128/2547.53.46.129 to 47.53.46.25447.53.46.255126
9547.53.47.0/2547.53.47.1 to 47.53.47.12647.53.47.127126
9647.53.47.128/2547.53.47.129 to 47.53.47.25447.53.47.255126
9747.53.48.0/2547.53.48.1 to 47.53.48.12647.53.48.127126
9847.53.48.128/2547.53.48.129 to 47.53.48.25447.53.48.255126
9947.53.49.0/2547.53.49.1 to 47.53.49.12647.53.49.127126
10047.53.49.128/2547.53.49.129 to 47.53.49.25447.53.49.255126
10147.53.50.0/2547.53.50.1 to 47.53.50.12647.53.50.127126
10247.53.50.128/2547.53.50.129 to 47.53.50.25447.53.50.255126
10347.53.51.0/2547.53.51.1 to 47.53.51.12647.53.51.127126
10447.53.51.128/2547.53.51.129 to 47.53.51.25447.53.51.255126
10547.53.52.0/2547.53.52.1 to 47.53.52.12647.53.52.127126
10647.53.52.128/2547.53.52.129 to 47.53.52.25447.53.52.255126
10747.53.53.0/2547.53.53.1 to 47.53.53.12647.53.53.127126
10847.53.53.128/2547.53.53.129 to 47.53.53.25447.53.53.255126
10947.53.54.0/2547.53.54.1 to 47.53.54.12647.53.54.127126
11047.53.54.128/2547.53.54.129 to 47.53.54.25447.53.54.255126
11147.53.55.0/2547.53.55.1 to 47.53.55.12647.53.55.127126
11247.53.55.128/2547.53.55.129 to 47.53.55.25447.53.55.255126
11347.53.56.0/2547.53.56.1 to 47.53.56.12647.53.56.127126
11447.53.56.128/2547.53.56.129 to 47.53.56.25447.53.56.255126
11547.53.57.0/2547.53.57.1 to 47.53.57.12647.53.57.127126
11647.53.57.128/2547.53.57.129 to 47.53.57.25447.53.57.255126
11747.53.58.0/2547.53.58.1 to 47.53.58.12647.53.58.127126
11847.53.58.128/2547.53.58.129 to 47.53.58.25447.53.58.255126
11947.53.59.0/2547.53.59.1 to 47.53.59.12647.53.59.127126
12047.53.59.128/2547.53.59.129 to 47.53.59.25447.53.59.255126
12147.53.60.0/2547.53.60.1 to 47.53.60.12647.53.60.127126
12247.53.60.128/2547.53.60.129 to 47.53.60.25447.53.60.255126
12347.53.61.0/2547.53.61.1 to 47.53.61.12647.53.61.127126
12447.53.61.128/2547.53.61.129 to 47.53.61.25447.53.61.255126
12547.53.62.0/2547.53.62.1 to 47.53.62.12647.53.62.127126
12647.53.62.128/2547.53.62.129 to 47.53.62.25447.53.62.255126
12747.53.63.0/2547.53.63.1 to 47.53.63.12647.53.63.127126
12847.53.63.128/2547.53.63.129 to 47.53.63.25447.53.63.255126
12947.53.64.0/2547.53.64.1 to 47.53.64.12647.53.64.127126
13047.53.64.128/2547.53.64.129 to 47.53.64.25447.53.64.255126
13147.53.65.0/2547.53.65.1 to 47.53.65.12647.53.65.127126
13247.53.65.128/2547.53.65.129 to 47.53.65.25447.53.65.255126
13347.53.66.0/2547.53.66.1 to 47.53.66.12647.53.66.127126
13447.53.66.128/2547.53.66.129 to 47.53.66.25447.53.66.255126
13547.53.67.0/2547.53.67.1 to 47.53.67.12647.53.67.127126
13647.53.67.128/2547.53.67.129 to 47.53.67.25447.53.67.255126
13747.53.68.0/2547.53.68.1 to 47.53.68.12647.53.68.127126
13847.53.68.128/2547.53.68.129 to 47.53.68.25447.53.68.255126
13947.53.69.0/2547.53.69.1 to 47.53.69.12647.53.69.127126
14047.53.69.128/2547.53.69.129 to 47.53.69.25447.53.69.255126
14147.53.70.0/2547.53.70.1 to 47.53.70.12647.53.70.127126
14247.53.70.128/2547.53.70.129 to 47.53.70.25447.53.70.255126
14347.53.71.0/2547.53.71.1 to 47.53.71.12647.53.71.127126
14447.53.71.128/2547.53.71.129 to 47.53.71.25447.53.71.255126
14547.53.72.0/2547.53.72.1 to 47.53.72.12647.53.72.127126
14647.53.72.128/2547.53.72.129 to 47.53.72.25447.53.72.255126
14747.53.73.0/2547.53.73.1 to 47.53.73.12647.53.73.127126
14847.53.73.128/2547.53.73.129 to 47.53.73.25447.53.73.255126
14947.53.74.0/2547.53.74.1 to 47.53.74.12647.53.74.127126
15047.53.74.128/2547.53.74.129 to 47.53.74.25447.53.74.255126
15147.53.75.0/2547.53.75.1 to 47.53.75.12647.53.75.127126
15247.53.75.128/2547.53.75.129 to 47.53.75.25447.53.75.255126
15347.53.76.0/2547.53.76.1 to 47.53.76.12647.53.76.127126
15447.53.76.128/2547.53.76.129 to 47.53.76.25447.53.76.255126
15547.53.77.0/2547.53.77.1 to 47.53.77.12647.53.77.127126
15647.53.77.128/2547.53.77.129 to 47.53.77.25447.53.77.255126
15747.53.78.0/2547.53.78.1 to 47.53.78.12647.53.78.127126
15847.53.78.128/2547.53.78.129 to 47.53.78.25447.53.78.255126
15947.53.79.0/2547.53.79.1 to 47.53.79.12647.53.79.127126
16047.53.79.128/2547.53.79.129 to 47.53.79.25447.53.79.255126
16147.53.80.0/2547.53.80.1 to 47.53.80.12647.53.80.127126
16247.53.80.128/2547.53.80.129 to 47.53.80.25447.53.80.255126
16347.53.81.0/2547.53.81.1 to 47.53.81.12647.53.81.127126
16447.53.81.128/2547.53.81.129 to 47.53.81.25447.53.81.255126
16547.53.82.0/2547.53.82.1 to 47.53.82.12647.53.82.127126
16647.53.82.128/2547.53.82.129 to 47.53.82.25447.53.82.255126
16747.53.83.0/2547.53.83.1 to 47.53.83.12647.53.83.127126
16847.53.83.128/2547.53.83.129 to 47.53.83.25447.53.83.255126
16947.53.84.0/2547.53.84.1 to 47.53.84.12647.53.84.127126
17047.53.84.128/2547.53.84.129 to 47.53.84.25447.53.84.255126
17147.53.85.0/2547.53.85.1 to 47.53.85.12647.53.85.127126
17247.53.85.128/2547.53.85.129 to 47.53.85.25447.53.85.255126
17347.53.86.0/2547.53.86.1 to 47.53.86.12647.53.86.127126
17447.53.86.128/2547.53.86.129 to 47.53.86.25447.53.86.255126
17547.53.87.0/2547.53.87.1 to 47.53.87.12647.53.87.127126
17647.53.87.128/2547.53.87.129 to 47.53.87.25447.53.87.255126
17747.53.88.0/2547.53.88.1 to 47.53.88.12647.53.88.127126
17847.53.88.128/2547.53.88.129 to 47.53.88.25447.53.88.255126
17947.53.89.0/2547.53.89.1 to 47.53.89.12647.53.89.127126
18047.53.89.128/2547.53.89.129 to 47.53.89.25447.53.89.255126
18147.53.90.0/2547.53.90.1 to 47.53.90.12647.53.90.127126
18247.53.90.128/2547.53.90.129 to 47.53.90.25447.53.90.255126
18347.53.91.0/2547.53.91.1 to 47.53.91.12647.53.91.127126
18447.53.91.128/2547.53.91.129 to 47.53.91.25447.53.91.255126
18547.53.92.0/2547.53.92.1 to 47.53.92.12647.53.92.127126
18647.53.92.128/2547.53.92.129 to 47.53.92.25447.53.92.255126
18747.53.93.0/2547.53.93.1 to 47.53.93.12647.53.93.127126
18847.53.93.128/2547.53.93.129 to 47.53.93.25447.53.93.255126
18947.53.94.0/2547.53.94.1 to 47.53.94.12647.53.94.127126
19047.53.94.128/2547.53.94.129 to 47.53.94.25447.53.94.255126
19147.53.95.0/2547.53.95.1 to 47.53.95.12647.53.95.127126
19247.53.95.128/2547.53.95.129 to 47.53.95.25447.53.95.255126
19347.53.96.0/2547.53.96.1 to 47.53.96.12647.53.96.127126
19447.53.96.128/2547.53.96.129 to 47.53.96.25447.53.96.255126
19547.53.97.0/2547.53.97.1 to 47.53.97.12647.53.97.127126
19647.53.97.128/2547.53.97.129 to 47.53.97.25447.53.97.255126
19747.53.98.0/2547.53.98.1 to 47.53.98.12647.53.98.127126
19847.53.98.128/2547.53.98.129 to 47.53.98.25447.53.98.255126
19947.53.99.0/2547.53.99.1 to 47.53.99.12647.53.99.127126
20047.53.99.128/2547.53.99.129 to 47.53.99.25447.53.99.255126
20147.53.100.0/2547.53.100.1 to 47.53.100.12647.53.100.127126
20247.53.100.128/2547.53.100.129 to 47.53.100.25447.53.100.255126
20347.53.101.0/2547.53.101.1 to 47.53.101.12647.53.101.127126
20447.53.101.128/2547.53.101.129 to 47.53.101.25447.53.101.255126
20547.53.102.0/2547.53.102.1 to 47.53.102.12647.53.102.127126
20647.53.102.128/2547.53.102.129 to 47.53.102.25447.53.102.255126
20747.53.103.0/2547.53.103.1 to 47.53.103.12647.53.103.127126
20847.53.103.128/2547.53.103.129 to 47.53.103.25447.53.103.255126
20947.53.104.0/2547.53.104.1 to 47.53.104.12647.53.104.127126
21047.53.104.128/2547.53.104.129 to 47.53.104.25447.53.104.255126
21147.53.105.0/2547.53.105.1 to 47.53.105.12647.53.105.127126
21247.53.105.128/2547.53.105.129 to 47.53.105.25447.53.105.255126
21347.53.106.0/2547.53.106.1 to 47.53.106.12647.53.106.127126
21447.53.106.128/2547.53.106.129 to 47.53.106.25447.53.106.255126
21547.53.107.0/2547.53.107.1 to 47.53.107.12647.53.107.127126
21647.53.107.128/2547.53.107.129 to 47.53.107.25447.53.107.255126
21747.53.108.0/2547.53.108.1 to 47.53.108.12647.53.108.127126
21847.53.108.128/2547.53.108.129 to 47.53.108.25447.53.108.255126
21947.53.109.0/2547.53.109.1 to 47.53.109.12647.53.109.127126
22047.53.109.128/2547.53.109.129 to 47.53.109.25447.53.109.255126
22147.53.110.0/2547.53.110.1 to 47.53.110.12647.53.110.127126
22247.53.110.128/2547.53.110.129 to 47.53.110.25447.53.110.255126
22347.53.111.0/2547.53.111.1 to 47.53.111.12647.53.111.127126
22447.53.111.128/2547.53.111.129 to 47.53.111.25447.53.111.255126
22547.53.112.0/2547.53.112.1 to 47.53.112.12647.53.112.127126
22647.53.112.128/2547.53.112.129 to 47.53.112.25447.53.112.255126
22747.53.113.0/2547.53.113.1 to 47.53.113.12647.53.113.127126
22847.53.113.128/2547.53.113.129 to 47.53.113.25447.53.113.255126
22947.53.114.0/2547.53.114.1 to 47.53.114.12647.53.114.127126
23047.53.114.128/2547.53.114.129 to 47.53.114.25447.53.114.255126
23147.53.115.0/2547.53.115.1 to 47.53.115.12647.53.115.127126
23247.53.115.128/2547.53.115.129 to 47.53.115.25447.53.115.255126
23347.53.116.0/2547.53.116.1 to 47.53.116.12647.53.116.127126
23447.53.116.128/2547.53.116.129 to 47.53.116.25447.53.116.255126
23547.53.117.0/2547.53.117.1 to 47.53.117.12647.53.117.127126
23647.53.117.128/2547.53.117.129 to 47.53.117.25447.53.117.255126
23747.53.118.0/2547.53.118.1 to 47.53.118.12647.53.118.127126
23847.53.118.128/2547.53.118.129 to 47.53.118.25447.53.118.255126
23947.53.119.0/2547.53.119.1 to 47.53.119.12647.53.119.127126
24047.53.119.128/2547.53.119.129 to 47.53.119.25447.53.119.255126
24147.53.120.0/2547.53.120.1 to 47.53.120.12647.53.120.127126
24247.53.120.128/2547.53.120.129 to 47.53.120.25447.53.120.255126
24347.53.121.0/2547.53.121.1 to 47.53.121.12647.53.121.127126
24447.53.121.128/2547.53.121.129 to 47.53.121.25447.53.121.255126
24547.53.122.0/2547.53.122.1 to 47.53.122.12647.53.122.127126
24647.53.122.128/2547.53.122.129 to 47.53.122.25447.53.122.255126
24747.53.123.0/2547.53.123.1 to 47.53.123.12647.53.123.127126
24847.53.123.128/2547.53.123.129 to 47.53.123.25447.53.123.255126
24947.53.124.0/2547.53.124.1 to 47.53.124.12647.53.124.127126
25047.53.124.128/2547.53.124.129 to 47.53.124.25447.53.124.255126
25147.53.125.0/2547.53.125.1 to 47.53.125.12647.53.125.127126
25247.53.125.128/2547.53.125.129 to 47.53.125.25447.53.125.255126
25347.53.126.0/2547.53.126.1 to 47.53.126.12647.53.126.127126
25447.53.126.128/2547.53.126.129 to 47.53.126.25447.53.126.255126
25547.53.127.0/2547.53.127.1 to 47.53.127.12647.53.127.127126
25647.53.127.128/2547.53.127.129 to 47.53.127.25447.53.127.255126

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.