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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.

Network69.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
69.0.0.0
Broadcast address
69.255.255.255
First usable
69.0.0.1
Last usable
69.255.255.254
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 45000000 · Integer 1157627904 to 1174405119
Reverse DNS zone
69.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01000101..00000000.00000000.0000000069.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01000101..00000000.00000000.0000000069.0.0.0
Broadcast01000101..11111111.11111111.1111111169.255.255.255
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)

69.0.0.0/8 makes 512 subnets of /17; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
169.0.0.0/1769.0.0.1 to 69.0.127.25469.0.127.25532,766
269.0.128.0/1769.0.128.1 to 69.0.255.25469.0.255.25532,766
369.1.0.0/1769.1.0.1 to 69.1.127.25469.1.127.25532,766
469.1.128.0/1769.1.128.1 to 69.1.255.25469.1.255.25532,766
569.2.0.0/1769.2.0.1 to 69.2.127.25469.2.127.25532,766
669.2.128.0/1769.2.128.1 to 69.2.255.25469.2.255.25532,766
769.3.0.0/1769.3.0.1 to 69.3.127.25469.3.127.25532,766
869.3.128.0/1769.3.128.1 to 69.3.255.25469.3.255.25532,766
969.4.0.0/1769.4.0.1 to 69.4.127.25469.4.127.25532,766
1069.4.128.0/1769.4.128.1 to 69.4.255.25469.4.255.25532,766
1169.5.0.0/1769.5.0.1 to 69.5.127.25469.5.127.25532,766
1269.5.128.0/1769.5.128.1 to 69.5.255.25469.5.255.25532,766
1369.6.0.0/1769.6.0.1 to 69.6.127.25469.6.127.25532,766
1469.6.128.0/1769.6.128.1 to 69.6.255.25469.6.255.25532,766
1569.7.0.0/1769.7.0.1 to 69.7.127.25469.7.127.25532,766
1669.7.128.0/1769.7.128.1 to 69.7.255.25469.7.255.25532,766
1769.8.0.0/1769.8.0.1 to 69.8.127.25469.8.127.25532,766
1869.8.128.0/1769.8.128.1 to 69.8.255.25469.8.255.25532,766
1969.9.0.0/1769.9.0.1 to 69.9.127.25469.9.127.25532,766
2069.9.128.0/1769.9.128.1 to 69.9.255.25469.9.255.25532,766
2169.10.0.0/1769.10.0.1 to 69.10.127.25469.10.127.25532,766
2269.10.128.0/1769.10.128.1 to 69.10.255.25469.10.255.25532,766
2369.11.0.0/1769.11.0.1 to 69.11.127.25469.11.127.25532,766
2469.11.128.0/1769.11.128.1 to 69.11.255.25469.11.255.25532,766
2569.12.0.0/1769.12.0.1 to 69.12.127.25469.12.127.25532,766
2669.12.128.0/1769.12.128.1 to 69.12.255.25469.12.255.25532,766
2769.13.0.0/1769.13.0.1 to 69.13.127.25469.13.127.25532,766
2869.13.128.0/1769.13.128.1 to 69.13.255.25469.13.255.25532,766
2969.14.0.0/1769.14.0.1 to 69.14.127.25469.14.127.25532,766
3069.14.128.0/1769.14.128.1 to 69.14.255.25469.14.255.25532,766
3169.15.0.0/1769.15.0.1 to 69.15.127.25469.15.127.25532,766
3269.15.128.0/1769.15.128.1 to 69.15.255.25469.15.255.25532,766
3369.16.0.0/1769.16.0.1 to 69.16.127.25469.16.127.25532,766
3469.16.128.0/1769.16.128.1 to 69.16.255.25469.16.255.25532,766
3569.17.0.0/1769.17.0.1 to 69.17.127.25469.17.127.25532,766
3669.17.128.0/1769.17.128.1 to 69.17.255.25469.17.255.25532,766
3769.18.0.0/1769.18.0.1 to 69.18.127.25469.18.127.25532,766
3869.18.128.0/1769.18.128.1 to 69.18.255.25469.18.255.25532,766
3969.19.0.0/1769.19.0.1 to 69.19.127.25469.19.127.25532,766
4069.19.128.0/1769.19.128.1 to 69.19.255.25469.19.255.25532,766
4169.20.0.0/1769.20.0.1 to 69.20.127.25469.20.127.25532,766
4269.20.128.0/1769.20.128.1 to 69.20.255.25469.20.255.25532,766
4369.21.0.0/1769.21.0.1 to 69.21.127.25469.21.127.25532,766
4469.21.128.0/1769.21.128.1 to 69.21.255.25469.21.255.25532,766
4569.22.0.0/1769.22.0.1 to 69.22.127.25469.22.127.25532,766
4669.22.128.0/1769.22.128.1 to 69.22.255.25469.22.255.25532,766
4769.23.0.0/1769.23.0.1 to 69.23.127.25469.23.127.25532,766
4869.23.128.0/1769.23.128.1 to 69.23.255.25469.23.255.25532,766
4969.24.0.0/1769.24.0.1 to 69.24.127.25469.24.127.25532,766
5069.24.128.0/1769.24.128.1 to 69.24.255.25469.24.255.25532,766
5169.25.0.0/1769.25.0.1 to 69.25.127.25469.25.127.25532,766
5269.25.128.0/1769.25.128.1 to 69.25.255.25469.25.255.25532,766
5369.26.0.0/1769.26.0.1 to 69.26.127.25469.26.127.25532,766
5469.26.128.0/1769.26.128.1 to 69.26.255.25469.26.255.25532,766
5569.27.0.0/1769.27.0.1 to 69.27.127.25469.27.127.25532,766
5669.27.128.0/1769.27.128.1 to 69.27.255.25469.27.255.25532,766
5769.28.0.0/1769.28.0.1 to 69.28.127.25469.28.127.25532,766
5869.28.128.0/1769.28.128.1 to 69.28.255.25469.28.255.25532,766
5969.29.0.0/1769.29.0.1 to 69.29.127.25469.29.127.25532,766
6069.29.128.0/1769.29.128.1 to 69.29.255.25469.29.255.25532,766
6169.30.0.0/1769.30.0.1 to 69.30.127.25469.30.127.25532,766
6269.30.128.0/1769.30.128.1 to 69.30.255.25469.30.255.25532,766
6369.31.0.0/1769.31.0.1 to 69.31.127.25469.31.127.25532,766
6469.31.128.0/1769.31.128.1 to 69.31.255.25469.31.255.25532,766
6569.32.0.0/1769.32.0.1 to 69.32.127.25469.32.127.25532,766
6669.32.128.0/1769.32.128.1 to 69.32.255.25469.32.255.25532,766
6769.33.0.0/1769.33.0.1 to 69.33.127.25469.33.127.25532,766
6869.33.128.0/1769.33.128.1 to 69.33.255.25469.33.255.25532,766
6969.34.0.0/1769.34.0.1 to 69.34.127.25469.34.127.25532,766
7069.34.128.0/1769.34.128.1 to 69.34.255.25469.34.255.25532,766
7169.35.0.0/1769.35.0.1 to 69.35.127.25469.35.127.25532,766
7269.35.128.0/1769.35.128.1 to 69.35.255.25469.35.255.25532,766
7369.36.0.0/1769.36.0.1 to 69.36.127.25469.36.127.25532,766
7469.36.128.0/1769.36.128.1 to 69.36.255.25469.36.255.25532,766
7569.37.0.0/1769.37.0.1 to 69.37.127.25469.37.127.25532,766
7669.37.128.0/1769.37.128.1 to 69.37.255.25469.37.255.25532,766
7769.38.0.0/1769.38.0.1 to 69.38.127.25469.38.127.25532,766
7869.38.128.0/1769.38.128.1 to 69.38.255.25469.38.255.25532,766
7969.39.0.0/1769.39.0.1 to 69.39.127.25469.39.127.25532,766
8069.39.128.0/1769.39.128.1 to 69.39.255.25469.39.255.25532,766
8169.40.0.0/1769.40.0.1 to 69.40.127.25469.40.127.25532,766
8269.40.128.0/1769.40.128.1 to 69.40.255.25469.40.255.25532,766
8369.41.0.0/1769.41.0.1 to 69.41.127.25469.41.127.25532,766
8469.41.128.0/1769.41.128.1 to 69.41.255.25469.41.255.25532,766
8569.42.0.0/1769.42.0.1 to 69.42.127.25469.42.127.25532,766
8669.42.128.0/1769.42.128.1 to 69.42.255.25469.42.255.25532,766
8769.43.0.0/1769.43.0.1 to 69.43.127.25469.43.127.25532,766
8869.43.128.0/1769.43.128.1 to 69.43.255.25469.43.255.25532,766
8969.44.0.0/1769.44.0.1 to 69.44.127.25469.44.127.25532,766
9069.44.128.0/1769.44.128.1 to 69.44.255.25469.44.255.25532,766
9169.45.0.0/1769.45.0.1 to 69.45.127.25469.45.127.25532,766
9269.45.128.0/1769.45.128.1 to 69.45.255.25469.45.255.25532,766
9369.46.0.0/1769.46.0.1 to 69.46.127.25469.46.127.25532,766
9469.46.128.0/1769.46.128.1 to 69.46.255.25469.46.255.25532,766
9569.47.0.0/1769.47.0.1 to 69.47.127.25469.47.127.25532,766
9669.47.128.0/1769.47.128.1 to 69.47.255.25469.47.255.25532,766
9769.48.0.0/1769.48.0.1 to 69.48.127.25469.48.127.25532,766
9869.48.128.0/1769.48.128.1 to 69.48.255.25469.48.255.25532,766
9969.49.0.0/1769.49.0.1 to 69.49.127.25469.49.127.25532,766
10069.49.128.0/1769.49.128.1 to 69.49.255.25469.49.255.25532,766
10169.50.0.0/1769.50.0.1 to 69.50.127.25469.50.127.25532,766
10269.50.128.0/1769.50.128.1 to 69.50.255.25469.50.255.25532,766
10369.51.0.0/1769.51.0.1 to 69.51.127.25469.51.127.25532,766
10469.51.128.0/1769.51.128.1 to 69.51.255.25469.51.255.25532,766
10569.52.0.0/1769.52.0.1 to 69.52.127.25469.52.127.25532,766
10669.52.128.0/1769.52.128.1 to 69.52.255.25469.52.255.25532,766
10769.53.0.0/1769.53.0.1 to 69.53.127.25469.53.127.25532,766
10869.53.128.0/1769.53.128.1 to 69.53.255.25469.53.255.25532,766
10969.54.0.0/1769.54.0.1 to 69.54.127.25469.54.127.25532,766
11069.54.128.0/1769.54.128.1 to 69.54.255.25469.54.255.25532,766
11169.55.0.0/1769.55.0.1 to 69.55.127.25469.55.127.25532,766
11269.55.128.0/1769.55.128.1 to 69.55.255.25469.55.255.25532,766
11369.56.0.0/1769.56.0.1 to 69.56.127.25469.56.127.25532,766
11469.56.128.0/1769.56.128.1 to 69.56.255.25469.56.255.25532,766
11569.57.0.0/1769.57.0.1 to 69.57.127.25469.57.127.25532,766
11669.57.128.0/1769.57.128.1 to 69.57.255.25469.57.255.25532,766
11769.58.0.0/1769.58.0.1 to 69.58.127.25469.58.127.25532,766
11869.58.128.0/1769.58.128.1 to 69.58.255.25469.58.255.25532,766
11969.59.0.0/1769.59.0.1 to 69.59.127.25469.59.127.25532,766
12069.59.128.0/1769.59.128.1 to 69.59.255.25469.59.255.25532,766
12169.60.0.0/1769.60.0.1 to 69.60.127.25469.60.127.25532,766
12269.60.128.0/1769.60.128.1 to 69.60.255.25469.60.255.25532,766
12369.61.0.0/1769.61.0.1 to 69.61.127.25469.61.127.25532,766
12469.61.128.0/1769.61.128.1 to 69.61.255.25469.61.255.25532,766
12569.62.0.0/1769.62.0.1 to 69.62.127.25469.62.127.25532,766
12669.62.128.0/1769.62.128.1 to 69.62.255.25469.62.255.25532,766
12769.63.0.0/1769.63.0.1 to 69.63.127.25469.63.127.25532,766
12869.63.128.0/1769.63.128.1 to 69.63.255.25469.63.255.25532,766
12969.64.0.0/1769.64.0.1 to 69.64.127.25469.64.127.25532,766
13069.64.128.0/1769.64.128.1 to 69.64.255.25469.64.255.25532,766
13169.65.0.0/1769.65.0.1 to 69.65.127.25469.65.127.25532,766
13269.65.128.0/1769.65.128.1 to 69.65.255.25469.65.255.25532,766
13369.66.0.0/1769.66.0.1 to 69.66.127.25469.66.127.25532,766
13469.66.128.0/1769.66.128.1 to 69.66.255.25469.66.255.25532,766
13569.67.0.0/1769.67.0.1 to 69.67.127.25469.67.127.25532,766
13669.67.128.0/1769.67.128.1 to 69.67.255.25469.67.255.25532,766
13769.68.0.0/1769.68.0.1 to 69.68.127.25469.68.127.25532,766
13869.68.128.0/1769.68.128.1 to 69.68.255.25469.68.255.25532,766
13969.69.0.0/1769.69.0.1 to 69.69.127.25469.69.127.25532,766
14069.69.128.0/1769.69.128.1 to 69.69.255.25469.69.255.25532,766
14169.70.0.0/1769.70.0.1 to 69.70.127.25469.70.127.25532,766
14269.70.128.0/1769.70.128.1 to 69.70.255.25469.70.255.25532,766
14369.71.0.0/1769.71.0.1 to 69.71.127.25469.71.127.25532,766
14469.71.128.0/1769.71.128.1 to 69.71.255.25469.71.255.25532,766
14569.72.0.0/1769.72.0.1 to 69.72.127.25469.72.127.25532,766
14669.72.128.0/1769.72.128.1 to 69.72.255.25469.72.255.25532,766
14769.73.0.0/1769.73.0.1 to 69.73.127.25469.73.127.25532,766
14869.73.128.0/1769.73.128.1 to 69.73.255.25469.73.255.25532,766
14969.74.0.0/1769.74.0.1 to 69.74.127.25469.74.127.25532,766
15069.74.128.0/1769.74.128.1 to 69.74.255.25469.74.255.25532,766
15169.75.0.0/1769.75.0.1 to 69.75.127.25469.75.127.25532,766
15269.75.128.0/1769.75.128.1 to 69.75.255.25469.75.255.25532,766
15369.76.0.0/1769.76.0.1 to 69.76.127.25469.76.127.25532,766
15469.76.128.0/1769.76.128.1 to 69.76.255.25469.76.255.25532,766
15569.77.0.0/1769.77.0.1 to 69.77.127.25469.77.127.25532,766
15669.77.128.0/1769.77.128.1 to 69.77.255.25469.77.255.25532,766
15769.78.0.0/1769.78.0.1 to 69.78.127.25469.78.127.25532,766
15869.78.128.0/1769.78.128.1 to 69.78.255.25469.78.255.25532,766
15969.79.0.0/1769.79.0.1 to 69.79.127.25469.79.127.25532,766
16069.79.128.0/1769.79.128.1 to 69.79.255.25469.79.255.25532,766
16169.80.0.0/1769.80.0.1 to 69.80.127.25469.80.127.25532,766
16269.80.128.0/1769.80.128.1 to 69.80.255.25469.80.255.25532,766
16369.81.0.0/1769.81.0.1 to 69.81.127.25469.81.127.25532,766
16469.81.128.0/1769.81.128.1 to 69.81.255.25469.81.255.25532,766
16569.82.0.0/1769.82.0.1 to 69.82.127.25469.82.127.25532,766
16669.82.128.0/1769.82.128.1 to 69.82.255.25469.82.255.25532,766
16769.83.0.0/1769.83.0.1 to 69.83.127.25469.83.127.25532,766
16869.83.128.0/1769.83.128.1 to 69.83.255.25469.83.255.25532,766
16969.84.0.0/1769.84.0.1 to 69.84.127.25469.84.127.25532,766
17069.84.128.0/1769.84.128.1 to 69.84.255.25469.84.255.25532,766
17169.85.0.0/1769.85.0.1 to 69.85.127.25469.85.127.25532,766
17269.85.128.0/1769.85.128.1 to 69.85.255.25469.85.255.25532,766
17369.86.0.0/1769.86.0.1 to 69.86.127.25469.86.127.25532,766
17469.86.128.0/1769.86.128.1 to 69.86.255.25469.86.255.25532,766
17569.87.0.0/1769.87.0.1 to 69.87.127.25469.87.127.25532,766
17669.87.128.0/1769.87.128.1 to 69.87.255.25469.87.255.25532,766
17769.88.0.0/1769.88.0.1 to 69.88.127.25469.88.127.25532,766
17869.88.128.0/1769.88.128.1 to 69.88.255.25469.88.255.25532,766
17969.89.0.0/1769.89.0.1 to 69.89.127.25469.89.127.25532,766
18069.89.128.0/1769.89.128.1 to 69.89.255.25469.89.255.25532,766
18169.90.0.0/1769.90.0.1 to 69.90.127.25469.90.127.25532,766
18269.90.128.0/1769.90.128.1 to 69.90.255.25469.90.255.25532,766
18369.91.0.0/1769.91.0.1 to 69.91.127.25469.91.127.25532,766
18469.91.128.0/1769.91.128.1 to 69.91.255.25469.91.255.25532,766
18569.92.0.0/1769.92.0.1 to 69.92.127.25469.92.127.25532,766
18669.92.128.0/1769.92.128.1 to 69.92.255.25469.92.255.25532,766
18769.93.0.0/1769.93.0.1 to 69.93.127.25469.93.127.25532,766
18869.93.128.0/1769.93.128.1 to 69.93.255.25469.93.255.25532,766
18969.94.0.0/1769.94.0.1 to 69.94.127.25469.94.127.25532,766
19069.94.128.0/1769.94.128.1 to 69.94.255.25469.94.255.25532,766
19169.95.0.0/1769.95.0.1 to 69.95.127.25469.95.127.25532,766
19269.95.128.0/1769.95.128.1 to 69.95.255.25469.95.255.25532,766
19369.96.0.0/1769.96.0.1 to 69.96.127.25469.96.127.25532,766
19469.96.128.0/1769.96.128.1 to 69.96.255.25469.96.255.25532,766
19569.97.0.0/1769.97.0.1 to 69.97.127.25469.97.127.25532,766
19669.97.128.0/1769.97.128.1 to 69.97.255.25469.97.255.25532,766
19769.98.0.0/1769.98.0.1 to 69.98.127.25469.98.127.25532,766
19869.98.128.0/1769.98.128.1 to 69.98.255.25469.98.255.25532,766
19969.99.0.0/1769.99.0.1 to 69.99.127.25469.99.127.25532,766
20069.99.128.0/1769.99.128.1 to 69.99.255.25469.99.255.25532,766
20169.100.0.0/1769.100.0.1 to 69.100.127.25469.100.127.25532,766
20269.100.128.0/1769.100.128.1 to 69.100.255.25469.100.255.25532,766
20369.101.0.0/1769.101.0.1 to 69.101.127.25469.101.127.25532,766
20469.101.128.0/1769.101.128.1 to 69.101.255.25469.101.255.25532,766
20569.102.0.0/1769.102.0.1 to 69.102.127.25469.102.127.25532,766
20669.102.128.0/1769.102.128.1 to 69.102.255.25469.102.255.25532,766
20769.103.0.0/1769.103.0.1 to 69.103.127.25469.103.127.25532,766
20869.103.128.0/1769.103.128.1 to 69.103.255.25469.103.255.25532,766
20969.104.0.0/1769.104.0.1 to 69.104.127.25469.104.127.25532,766
21069.104.128.0/1769.104.128.1 to 69.104.255.25469.104.255.25532,766
21169.105.0.0/1769.105.0.1 to 69.105.127.25469.105.127.25532,766
21269.105.128.0/1769.105.128.1 to 69.105.255.25469.105.255.25532,766
21369.106.0.0/1769.106.0.1 to 69.106.127.25469.106.127.25532,766
21469.106.128.0/1769.106.128.1 to 69.106.255.25469.106.255.25532,766
21569.107.0.0/1769.107.0.1 to 69.107.127.25469.107.127.25532,766
21669.107.128.0/1769.107.128.1 to 69.107.255.25469.107.255.25532,766
21769.108.0.0/1769.108.0.1 to 69.108.127.25469.108.127.25532,766
21869.108.128.0/1769.108.128.1 to 69.108.255.25469.108.255.25532,766
21969.109.0.0/1769.109.0.1 to 69.109.127.25469.109.127.25532,766
22069.109.128.0/1769.109.128.1 to 69.109.255.25469.109.255.25532,766
22169.110.0.0/1769.110.0.1 to 69.110.127.25469.110.127.25532,766
22269.110.128.0/1769.110.128.1 to 69.110.255.25469.110.255.25532,766
22369.111.0.0/1769.111.0.1 to 69.111.127.25469.111.127.25532,766
22469.111.128.0/1769.111.128.1 to 69.111.255.25469.111.255.25532,766
22569.112.0.0/1769.112.0.1 to 69.112.127.25469.112.127.25532,766
22669.112.128.0/1769.112.128.1 to 69.112.255.25469.112.255.25532,766
22769.113.0.0/1769.113.0.1 to 69.113.127.25469.113.127.25532,766
22869.113.128.0/1769.113.128.1 to 69.113.255.25469.113.255.25532,766
22969.114.0.0/1769.114.0.1 to 69.114.127.25469.114.127.25532,766
23069.114.128.0/1769.114.128.1 to 69.114.255.25469.114.255.25532,766
23169.115.0.0/1769.115.0.1 to 69.115.127.25469.115.127.25532,766
23269.115.128.0/1769.115.128.1 to 69.115.255.25469.115.255.25532,766
23369.116.0.0/1769.116.0.1 to 69.116.127.25469.116.127.25532,766
23469.116.128.0/1769.116.128.1 to 69.116.255.25469.116.255.25532,766
23569.117.0.0/1769.117.0.1 to 69.117.127.25469.117.127.25532,766
23669.117.128.0/1769.117.128.1 to 69.117.255.25469.117.255.25532,766
23769.118.0.0/1769.118.0.1 to 69.118.127.25469.118.127.25532,766
23869.118.128.0/1769.118.128.1 to 69.118.255.25469.118.255.25532,766
23969.119.0.0/1769.119.0.1 to 69.119.127.25469.119.127.25532,766
24069.119.128.0/1769.119.128.1 to 69.119.255.25469.119.255.25532,766
24169.120.0.0/1769.120.0.1 to 69.120.127.25469.120.127.25532,766
24269.120.128.0/1769.120.128.1 to 69.120.255.25469.120.255.25532,766
24369.121.0.0/1769.121.0.1 to 69.121.127.25469.121.127.25532,766
24469.121.128.0/1769.121.128.1 to 69.121.255.25469.121.255.25532,766
24569.122.0.0/1769.122.0.1 to 69.122.127.25469.122.127.25532,766
24669.122.128.0/1769.122.128.1 to 69.122.255.25469.122.255.25532,766
24769.123.0.0/1769.123.0.1 to 69.123.127.25469.123.127.25532,766
24869.123.128.0/1769.123.128.1 to 69.123.255.25469.123.255.25532,766
24969.124.0.0/1769.124.0.1 to 69.124.127.25469.124.127.25532,766
25069.124.128.0/1769.124.128.1 to 69.124.255.25469.124.255.25532,766
25169.125.0.0/1769.125.0.1 to 69.125.127.25469.125.127.25532,766
25269.125.128.0/1769.125.128.1 to 69.125.255.25469.125.255.25532,766
25369.126.0.0/1769.126.0.1 to 69.126.127.25469.126.127.25532,766
25469.126.128.0/1769.126.128.1 to 69.126.255.25469.126.255.25532,766
25569.127.0.0/1769.127.0.1 to 69.127.127.25469.127.127.25532,766
25669.127.128.0/1769.127.128.1 to 69.127.255.25469.127.255.25532,766

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.