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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.

Network48.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
48.0.0.0
Broadcast address
49.255.255.255
First usable
48.0.0.1
Last usable
49.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 30000000 · Integer 805306368 to 838860799
Reverse DNS zones
48.in-addr.arpa
49.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110000.00000000.00000000.0000000048.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network00110000.00000000.00000000.0000000048.0.0.0
Broadcast00110001.11111111.11111111.1111111149.255.255.255
Split into smaller subnets/17
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

48.0.0.0/7 makes 1,024 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
148.0.0.0/1748.0.0.1 to 48.0.127.25448.0.127.25532,766
248.0.128.0/1748.0.128.1 to 48.0.255.25448.0.255.25532,766
348.1.0.0/1748.1.0.1 to 48.1.127.25448.1.127.25532,766
448.1.128.0/1748.1.128.1 to 48.1.255.25448.1.255.25532,766
548.2.0.0/1748.2.0.1 to 48.2.127.25448.2.127.25532,766
648.2.128.0/1748.2.128.1 to 48.2.255.25448.2.255.25532,766
748.3.0.0/1748.3.0.1 to 48.3.127.25448.3.127.25532,766
848.3.128.0/1748.3.128.1 to 48.3.255.25448.3.255.25532,766
948.4.0.0/1748.4.0.1 to 48.4.127.25448.4.127.25532,766
1048.4.128.0/1748.4.128.1 to 48.4.255.25448.4.255.25532,766
1148.5.0.0/1748.5.0.1 to 48.5.127.25448.5.127.25532,766
1248.5.128.0/1748.5.128.1 to 48.5.255.25448.5.255.25532,766
1348.6.0.0/1748.6.0.1 to 48.6.127.25448.6.127.25532,766
1448.6.128.0/1748.6.128.1 to 48.6.255.25448.6.255.25532,766
1548.7.0.0/1748.7.0.1 to 48.7.127.25448.7.127.25532,766
1648.7.128.0/1748.7.128.1 to 48.7.255.25448.7.255.25532,766
1748.8.0.0/1748.8.0.1 to 48.8.127.25448.8.127.25532,766
1848.8.128.0/1748.8.128.1 to 48.8.255.25448.8.255.25532,766
1948.9.0.0/1748.9.0.1 to 48.9.127.25448.9.127.25532,766
2048.9.128.0/1748.9.128.1 to 48.9.255.25448.9.255.25532,766
2148.10.0.0/1748.10.0.1 to 48.10.127.25448.10.127.25532,766
2248.10.128.0/1748.10.128.1 to 48.10.255.25448.10.255.25532,766
2348.11.0.0/1748.11.0.1 to 48.11.127.25448.11.127.25532,766
2448.11.128.0/1748.11.128.1 to 48.11.255.25448.11.255.25532,766
2548.12.0.0/1748.12.0.1 to 48.12.127.25448.12.127.25532,766
2648.12.128.0/1748.12.128.1 to 48.12.255.25448.12.255.25532,766
2748.13.0.0/1748.13.0.1 to 48.13.127.25448.13.127.25532,766
2848.13.128.0/1748.13.128.1 to 48.13.255.25448.13.255.25532,766
2948.14.0.0/1748.14.0.1 to 48.14.127.25448.14.127.25532,766
3048.14.128.0/1748.14.128.1 to 48.14.255.25448.14.255.25532,766
3148.15.0.0/1748.15.0.1 to 48.15.127.25448.15.127.25532,766
3248.15.128.0/1748.15.128.1 to 48.15.255.25448.15.255.25532,766
3348.16.0.0/1748.16.0.1 to 48.16.127.25448.16.127.25532,766
3448.16.128.0/1748.16.128.1 to 48.16.255.25448.16.255.25532,766
3548.17.0.0/1748.17.0.1 to 48.17.127.25448.17.127.25532,766
3648.17.128.0/1748.17.128.1 to 48.17.255.25448.17.255.25532,766
3748.18.0.0/1748.18.0.1 to 48.18.127.25448.18.127.25532,766
3848.18.128.0/1748.18.128.1 to 48.18.255.25448.18.255.25532,766
3948.19.0.0/1748.19.0.1 to 48.19.127.25448.19.127.25532,766
4048.19.128.0/1748.19.128.1 to 48.19.255.25448.19.255.25532,766
4148.20.0.0/1748.20.0.1 to 48.20.127.25448.20.127.25532,766
4248.20.128.0/1748.20.128.1 to 48.20.255.25448.20.255.25532,766
4348.21.0.0/1748.21.0.1 to 48.21.127.25448.21.127.25532,766
4448.21.128.0/1748.21.128.1 to 48.21.255.25448.21.255.25532,766
4548.22.0.0/1748.22.0.1 to 48.22.127.25448.22.127.25532,766
4648.22.128.0/1748.22.128.1 to 48.22.255.25448.22.255.25532,766
4748.23.0.0/1748.23.0.1 to 48.23.127.25448.23.127.25532,766
4848.23.128.0/1748.23.128.1 to 48.23.255.25448.23.255.25532,766
4948.24.0.0/1748.24.0.1 to 48.24.127.25448.24.127.25532,766
5048.24.128.0/1748.24.128.1 to 48.24.255.25448.24.255.25532,766
5148.25.0.0/1748.25.0.1 to 48.25.127.25448.25.127.25532,766
5248.25.128.0/1748.25.128.1 to 48.25.255.25448.25.255.25532,766
5348.26.0.0/1748.26.0.1 to 48.26.127.25448.26.127.25532,766
5448.26.128.0/1748.26.128.1 to 48.26.255.25448.26.255.25532,766
5548.27.0.0/1748.27.0.1 to 48.27.127.25448.27.127.25532,766
5648.27.128.0/1748.27.128.1 to 48.27.255.25448.27.255.25532,766
5748.28.0.0/1748.28.0.1 to 48.28.127.25448.28.127.25532,766
5848.28.128.0/1748.28.128.1 to 48.28.255.25448.28.255.25532,766
5948.29.0.0/1748.29.0.1 to 48.29.127.25448.29.127.25532,766
6048.29.128.0/1748.29.128.1 to 48.29.255.25448.29.255.25532,766
6148.30.0.0/1748.30.0.1 to 48.30.127.25448.30.127.25532,766
6248.30.128.0/1748.30.128.1 to 48.30.255.25448.30.255.25532,766
6348.31.0.0/1748.31.0.1 to 48.31.127.25448.31.127.25532,766
6448.31.128.0/1748.31.128.1 to 48.31.255.25448.31.255.25532,766
6548.32.0.0/1748.32.0.1 to 48.32.127.25448.32.127.25532,766
6648.32.128.0/1748.32.128.1 to 48.32.255.25448.32.255.25532,766
6748.33.0.0/1748.33.0.1 to 48.33.127.25448.33.127.25532,766
6848.33.128.0/1748.33.128.1 to 48.33.255.25448.33.255.25532,766
6948.34.0.0/1748.34.0.1 to 48.34.127.25448.34.127.25532,766
7048.34.128.0/1748.34.128.1 to 48.34.255.25448.34.255.25532,766
7148.35.0.0/1748.35.0.1 to 48.35.127.25448.35.127.25532,766
7248.35.128.0/1748.35.128.1 to 48.35.255.25448.35.255.25532,766
7348.36.0.0/1748.36.0.1 to 48.36.127.25448.36.127.25532,766
7448.36.128.0/1748.36.128.1 to 48.36.255.25448.36.255.25532,766
7548.37.0.0/1748.37.0.1 to 48.37.127.25448.37.127.25532,766
7648.37.128.0/1748.37.128.1 to 48.37.255.25448.37.255.25532,766
7748.38.0.0/1748.38.0.1 to 48.38.127.25448.38.127.25532,766
7848.38.128.0/1748.38.128.1 to 48.38.255.25448.38.255.25532,766
7948.39.0.0/1748.39.0.1 to 48.39.127.25448.39.127.25532,766
8048.39.128.0/1748.39.128.1 to 48.39.255.25448.39.255.25532,766
8148.40.0.0/1748.40.0.1 to 48.40.127.25448.40.127.25532,766
8248.40.128.0/1748.40.128.1 to 48.40.255.25448.40.255.25532,766
8348.41.0.0/1748.41.0.1 to 48.41.127.25448.41.127.25532,766
8448.41.128.0/1748.41.128.1 to 48.41.255.25448.41.255.25532,766
8548.42.0.0/1748.42.0.1 to 48.42.127.25448.42.127.25532,766
8648.42.128.0/1748.42.128.1 to 48.42.255.25448.42.255.25532,766
8748.43.0.0/1748.43.0.1 to 48.43.127.25448.43.127.25532,766
8848.43.128.0/1748.43.128.1 to 48.43.255.25448.43.255.25532,766
8948.44.0.0/1748.44.0.1 to 48.44.127.25448.44.127.25532,766
9048.44.128.0/1748.44.128.1 to 48.44.255.25448.44.255.25532,766
9148.45.0.0/1748.45.0.1 to 48.45.127.25448.45.127.25532,766
9248.45.128.0/1748.45.128.1 to 48.45.255.25448.45.255.25532,766
9348.46.0.0/1748.46.0.1 to 48.46.127.25448.46.127.25532,766
9448.46.128.0/1748.46.128.1 to 48.46.255.25448.46.255.25532,766
9548.47.0.0/1748.47.0.1 to 48.47.127.25448.47.127.25532,766
9648.47.128.0/1748.47.128.1 to 48.47.255.25448.47.255.25532,766
9748.48.0.0/1748.48.0.1 to 48.48.127.25448.48.127.25532,766
9848.48.128.0/1748.48.128.1 to 48.48.255.25448.48.255.25532,766
9948.49.0.0/1748.49.0.1 to 48.49.127.25448.49.127.25532,766
10048.49.128.0/1748.49.128.1 to 48.49.255.25448.49.255.25532,766
10148.50.0.0/1748.50.0.1 to 48.50.127.25448.50.127.25532,766
10248.50.128.0/1748.50.128.1 to 48.50.255.25448.50.255.25532,766
10348.51.0.0/1748.51.0.1 to 48.51.127.25448.51.127.25532,766
10448.51.128.0/1748.51.128.1 to 48.51.255.25448.51.255.25532,766
10548.52.0.0/1748.52.0.1 to 48.52.127.25448.52.127.25532,766
10648.52.128.0/1748.52.128.1 to 48.52.255.25448.52.255.25532,766
10748.53.0.0/1748.53.0.1 to 48.53.127.25448.53.127.25532,766
10848.53.128.0/1748.53.128.1 to 48.53.255.25448.53.255.25532,766
10948.54.0.0/1748.54.0.1 to 48.54.127.25448.54.127.25532,766
11048.54.128.0/1748.54.128.1 to 48.54.255.25448.54.255.25532,766
11148.55.0.0/1748.55.0.1 to 48.55.127.25448.55.127.25532,766
11248.55.128.0/1748.55.128.1 to 48.55.255.25448.55.255.25532,766
11348.56.0.0/1748.56.0.1 to 48.56.127.25448.56.127.25532,766
11448.56.128.0/1748.56.128.1 to 48.56.255.25448.56.255.25532,766
11548.57.0.0/1748.57.0.1 to 48.57.127.25448.57.127.25532,766
11648.57.128.0/1748.57.128.1 to 48.57.255.25448.57.255.25532,766
11748.58.0.0/1748.58.0.1 to 48.58.127.25448.58.127.25532,766
11848.58.128.0/1748.58.128.1 to 48.58.255.25448.58.255.25532,766
11948.59.0.0/1748.59.0.1 to 48.59.127.25448.59.127.25532,766
12048.59.128.0/1748.59.128.1 to 48.59.255.25448.59.255.25532,766
12148.60.0.0/1748.60.0.1 to 48.60.127.25448.60.127.25532,766
12248.60.128.0/1748.60.128.1 to 48.60.255.25448.60.255.25532,766
12348.61.0.0/1748.61.0.1 to 48.61.127.25448.61.127.25532,766
12448.61.128.0/1748.61.128.1 to 48.61.255.25448.61.255.25532,766
12548.62.0.0/1748.62.0.1 to 48.62.127.25448.62.127.25532,766
12648.62.128.0/1748.62.128.1 to 48.62.255.25448.62.255.25532,766
12748.63.0.0/1748.63.0.1 to 48.63.127.25448.63.127.25532,766
12848.63.128.0/1748.63.128.1 to 48.63.255.25448.63.255.25532,766
12948.64.0.0/1748.64.0.1 to 48.64.127.25448.64.127.25532,766
13048.64.128.0/1748.64.128.1 to 48.64.255.25448.64.255.25532,766
13148.65.0.0/1748.65.0.1 to 48.65.127.25448.65.127.25532,766
13248.65.128.0/1748.65.128.1 to 48.65.255.25448.65.255.25532,766
13348.66.0.0/1748.66.0.1 to 48.66.127.25448.66.127.25532,766
13448.66.128.0/1748.66.128.1 to 48.66.255.25448.66.255.25532,766
13548.67.0.0/1748.67.0.1 to 48.67.127.25448.67.127.25532,766
13648.67.128.0/1748.67.128.1 to 48.67.255.25448.67.255.25532,766
13748.68.0.0/1748.68.0.1 to 48.68.127.25448.68.127.25532,766
13848.68.128.0/1748.68.128.1 to 48.68.255.25448.68.255.25532,766
13948.69.0.0/1748.69.0.1 to 48.69.127.25448.69.127.25532,766
14048.69.128.0/1748.69.128.1 to 48.69.255.25448.69.255.25532,766
14148.70.0.0/1748.70.0.1 to 48.70.127.25448.70.127.25532,766
14248.70.128.0/1748.70.128.1 to 48.70.255.25448.70.255.25532,766
14348.71.0.0/1748.71.0.1 to 48.71.127.25448.71.127.25532,766
14448.71.128.0/1748.71.128.1 to 48.71.255.25448.71.255.25532,766
14548.72.0.0/1748.72.0.1 to 48.72.127.25448.72.127.25532,766
14648.72.128.0/1748.72.128.1 to 48.72.255.25448.72.255.25532,766
14748.73.0.0/1748.73.0.1 to 48.73.127.25448.73.127.25532,766
14848.73.128.0/1748.73.128.1 to 48.73.255.25448.73.255.25532,766
14948.74.0.0/1748.74.0.1 to 48.74.127.25448.74.127.25532,766
15048.74.128.0/1748.74.128.1 to 48.74.255.25448.74.255.25532,766
15148.75.0.0/1748.75.0.1 to 48.75.127.25448.75.127.25532,766
15248.75.128.0/1748.75.128.1 to 48.75.255.25448.75.255.25532,766
15348.76.0.0/1748.76.0.1 to 48.76.127.25448.76.127.25532,766
15448.76.128.0/1748.76.128.1 to 48.76.255.25448.76.255.25532,766
15548.77.0.0/1748.77.0.1 to 48.77.127.25448.77.127.25532,766
15648.77.128.0/1748.77.128.1 to 48.77.255.25448.77.255.25532,766
15748.78.0.0/1748.78.0.1 to 48.78.127.25448.78.127.25532,766
15848.78.128.0/1748.78.128.1 to 48.78.255.25448.78.255.25532,766
15948.79.0.0/1748.79.0.1 to 48.79.127.25448.79.127.25532,766
16048.79.128.0/1748.79.128.1 to 48.79.255.25448.79.255.25532,766
16148.80.0.0/1748.80.0.1 to 48.80.127.25448.80.127.25532,766
16248.80.128.0/1748.80.128.1 to 48.80.255.25448.80.255.25532,766
16348.81.0.0/1748.81.0.1 to 48.81.127.25448.81.127.25532,766
16448.81.128.0/1748.81.128.1 to 48.81.255.25448.81.255.25532,766
16548.82.0.0/1748.82.0.1 to 48.82.127.25448.82.127.25532,766
16648.82.128.0/1748.82.128.1 to 48.82.255.25448.82.255.25532,766
16748.83.0.0/1748.83.0.1 to 48.83.127.25448.83.127.25532,766
16848.83.128.0/1748.83.128.1 to 48.83.255.25448.83.255.25532,766
16948.84.0.0/1748.84.0.1 to 48.84.127.25448.84.127.25532,766
17048.84.128.0/1748.84.128.1 to 48.84.255.25448.84.255.25532,766
17148.85.0.0/1748.85.0.1 to 48.85.127.25448.85.127.25532,766
17248.85.128.0/1748.85.128.1 to 48.85.255.25448.85.255.25532,766
17348.86.0.0/1748.86.0.1 to 48.86.127.25448.86.127.25532,766
17448.86.128.0/1748.86.128.1 to 48.86.255.25448.86.255.25532,766
17548.87.0.0/1748.87.0.1 to 48.87.127.25448.87.127.25532,766
17648.87.128.0/1748.87.128.1 to 48.87.255.25448.87.255.25532,766
17748.88.0.0/1748.88.0.1 to 48.88.127.25448.88.127.25532,766
17848.88.128.0/1748.88.128.1 to 48.88.255.25448.88.255.25532,766
17948.89.0.0/1748.89.0.1 to 48.89.127.25448.89.127.25532,766
18048.89.128.0/1748.89.128.1 to 48.89.255.25448.89.255.25532,766
18148.90.0.0/1748.90.0.1 to 48.90.127.25448.90.127.25532,766
18248.90.128.0/1748.90.128.1 to 48.90.255.25448.90.255.25532,766
18348.91.0.0/1748.91.0.1 to 48.91.127.25448.91.127.25532,766
18448.91.128.0/1748.91.128.1 to 48.91.255.25448.91.255.25532,766
18548.92.0.0/1748.92.0.1 to 48.92.127.25448.92.127.25532,766
18648.92.128.0/1748.92.128.1 to 48.92.255.25448.92.255.25532,766
18748.93.0.0/1748.93.0.1 to 48.93.127.25448.93.127.25532,766
18848.93.128.0/1748.93.128.1 to 48.93.255.25448.93.255.25532,766
18948.94.0.0/1748.94.0.1 to 48.94.127.25448.94.127.25532,766
19048.94.128.0/1748.94.128.1 to 48.94.255.25448.94.255.25532,766
19148.95.0.0/1748.95.0.1 to 48.95.127.25448.95.127.25532,766
19248.95.128.0/1748.95.128.1 to 48.95.255.25448.95.255.25532,766
19348.96.0.0/1748.96.0.1 to 48.96.127.25448.96.127.25532,766
19448.96.128.0/1748.96.128.1 to 48.96.255.25448.96.255.25532,766
19548.97.0.0/1748.97.0.1 to 48.97.127.25448.97.127.25532,766
19648.97.128.0/1748.97.128.1 to 48.97.255.25448.97.255.25532,766
19748.98.0.0/1748.98.0.1 to 48.98.127.25448.98.127.25532,766
19848.98.128.0/1748.98.128.1 to 48.98.255.25448.98.255.25532,766
19948.99.0.0/1748.99.0.1 to 48.99.127.25448.99.127.25532,766
20048.99.128.0/1748.99.128.1 to 48.99.255.25448.99.255.25532,766
20148.100.0.0/1748.100.0.1 to 48.100.127.25448.100.127.25532,766
20248.100.128.0/1748.100.128.1 to 48.100.255.25448.100.255.25532,766
20348.101.0.0/1748.101.0.1 to 48.101.127.25448.101.127.25532,766
20448.101.128.0/1748.101.128.1 to 48.101.255.25448.101.255.25532,766
20548.102.0.0/1748.102.0.1 to 48.102.127.25448.102.127.25532,766
20648.102.128.0/1748.102.128.1 to 48.102.255.25448.102.255.25532,766
20748.103.0.0/1748.103.0.1 to 48.103.127.25448.103.127.25532,766
20848.103.128.0/1748.103.128.1 to 48.103.255.25448.103.255.25532,766
20948.104.0.0/1748.104.0.1 to 48.104.127.25448.104.127.25532,766
21048.104.128.0/1748.104.128.1 to 48.104.255.25448.104.255.25532,766
21148.105.0.0/1748.105.0.1 to 48.105.127.25448.105.127.25532,766
21248.105.128.0/1748.105.128.1 to 48.105.255.25448.105.255.25532,766
21348.106.0.0/1748.106.0.1 to 48.106.127.25448.106.127.25532,766
21448.106.128.0/1748.106.128.1 to 48.106.255.25448.106.255.25532,766
21548.107.0.0/1748.107.0.1 to 48.107.127.25448.107.127.25532,766
21648.107.128.0/1748.107.128.1 to 48.107.255.25448.107.255.25532,766
21748.108.0.0/1748.108.0.1 to 48.108.127.25448.108.127.25532,766
21848.108.128.0/1748.108.128.1 to 48.108.255.25448.108.255.25532,766
21948.109.0.0/1748.109.0.1 to 48.109.127.25448.109.127.25532,766
22048.109.128.0/1748.109.128.1 to 48.109.255.25448.109.255.25532,766
22148.110.0.0/1748.110.0.1 to 48.110.127.25448.110.127.25532,766
22248.110.128.0/1748.110.128.1 to 48.110.255.25448.110.255.25532,766
22348.111.0.0/1748.111.0.1 to 48.111.127.25448.111.127.25532,766
22448.111.128.0/1748.111.128.1 to 48.111.255.25448.111.255.25532,766
22548.112.0.0/1748.112.0.1 to 48.112.127.25448.112.127.25532,766
22648.112.128.0/1748.112.128.1 to 48.112.255.25448.112.255.25532,766
22748.113.0.0/1748.113.0.1 to 48.113.127.25448.113.127.25532,766
22848.113.128.0/1748.113.128.1 to 48.113.255.25448.113.255.25532,766
22948.114.0.0/1748.114.0.1 to 48.114.127.25448.114.127.25532,766
23048.114.128.0/1748.114.128.1 to 48.114.255.25448.114.255.25532,766
23148.115.0.0/1748.115.0.1 to 48.115.127.25448.115.127.25532,766
23248.115.128.0/1748.115.128.1 to 48.115.255.25448.115.255.25532,766
23348.116.0.0/1748.116.0.1 to 48.116.127.25448.116.127.25532,766
23448.116.128.0/1748.116.128.1 to 48.116.255.25448.116.255.25532,766
23548.117.0.0/1748.117.0.1 to 48.117.127.25448.117.127.25532,766
23648.117.128.0/1748.117.128.1 to 48.117.255.25448.117.255.25532,766
23748.118.0.0/1748.118.0.1 to 48.118.127.25448.118.127.25532,766
23848.118.128.0/1748.118.128.1 to 48.118.255.25448.118.255.25532,766
23948.119.0.0/1748.119.0.1 to 48.119.127.25448.119.127.25532,766
24048.119.128.0/1748.119.128.1 to 48.119.255.25448.119.255.25532,766
24148.120.0.0/1748.120.0.1 to 48.120.127.25448.120.127.25532,766
24248.120.128.0/1748.120.128.1 to 48.120.255.25448.120.255.25532,766
24348.121.0.0/1748.121.0.1 to 48.121.127.25448.121.127.25532,766
24448.121.128.0/1748.121.128.1 to 48.121.255.25448.121.255.25532,766
24548.122.0.0/1748.122.0.1 to 48.122.127.25448.122.127.25532,766
24648.122.128.0/1748.122.128.1 to 48.122.255.25448.122.255.25532,766
24748.123.0.0/1748.123.0.1 to 48.123.127.25448.123.127.25532,766
24848.123.128.0/1748.123.128.1 to 48.123.255.25448.123.255.25532,766
24948.124.0.0/1748.124.0.1 to 48.124.127.25448.124.127.25532,766
25048.124.128.0/1748.124.128.1 to 48.124.255.25448.124.255.25532,766
25148.125.0.0/1748.125.0.1 to 48.125.127.25448.125.127.25532,766
25248.125.128.0/1748.125.128.1 to 48.125.255.25448.125.255.25532,766
25348.126.0.0/1748.126.0.1 to 48.126.127.25448.126.127.25532,766
25448.126.128.0/1748.126.128.1 to 48.126.255.25448.126.255.25532,766
25548.127.0.0/1748.127.0.1 to 48.127.127.25448.127.127.25532,766
25648.127.128.0/1748.127.128.1 to 48.127.255.25448.127.255.25532,766

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.