Speed and call quality testMy IP addressIP subnet calculatorDNS reportWhoIs lookupRemote support

Internet and network

Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

Computers and devices

Update checkIs this computer, phone and browser up to date? With links to update.Camera and mic testCheck your webcam and microphone before a call.Test print pagePrint an A4 page to check a printer: edges, text, line art and colours.

Make and print

Clean textStrip hidden characters, smart quotes and odd spaces from pasted text.QR code makerMake a QR code for a link, contact or message. Nothing leaves your browser.Wi-Fi QR posterPrint an A4 poster that lets guests join your Wi-Fi by scanning.

Surftec support

Remote supportLet a Surftec engineer connect to your computer to help you.All workingA full-screen confirmation that everything is up and running.

Surftec

Surftec websiteServices, news and how to contact Surftec
Cloud Tools
Guest
GuestNot signed in

Surftec customers will be recognised automatically when they use these tools from their office network.

Customer sign-in is coming soon.

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.

Network96.182.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
96.182.0.0
Broadcast address
96.182.255.255
First usable
96.182.0.1
Last usable
96.182.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 60B60000 · Integer 1622540288 to 1622605823
Reverse DNS zone
182.96.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01100000.10110110..00000000.0000000096.182.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01100000.10110110..00000000.0000000096.182.0.0
Broadcast01100000.10110110..11111111.1111111196.182.255.255
Split into smaller subnets/25
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

96.182.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
196.182.0.0/2596.182.0.1 to 96.182.0.12696.182.0.127126
296.182.0.128/2596.182.0.129 to 96.182.0.25496.182.0.255126
396.182.1.0/2596.182.1.1 to 96.182.1.12696.182.1.127126
496.182.1.128/2596.182.1.129 to 96.182.1.25496.182.1.255126
596.182.2.0/2596.182.2.1 to 96.182.2.12696.182.2.127126
696.182.2.128/2596.182.2.129 to 96.182.2.25496.182.2.255126
796.182.3.0/2596.182.3.1 to 96.182.3.12696.182.3.127126
896.182.3.128/2596.182.3.129 to 96.182.3.25496.182.3.255126
996.182.4.0/2596.182.4.1 to 96.182.4.12696.182.4.127126
1096.182.4.128/2596.182.4.129 to 96.182.4.25496.182.4.255126
1196.182.5.0/2596.182.5.1 to 96.182.5.12696.182.5.127126
1296.182.5.128/2596.182.5.129 to 96.182.5.25496.182.5.255126
1396.182.6.0/2596.182.6.1 to 96.182.6.12696.182.6.127126
1496.182.6.128/2596.182.6.129 to 96.182.6.25496.182.6.255126
1596.182.7.0/2596.182.7.1 to 96.182.7.12696.182.7.127126
1696.182.7.128/2596.182.7.129 to 96.182.7.25496.182.7.255126
1796.182.8.0/2596.182.8.1 to 96.182.8.12696.182.8.127126
1896.182.8.128/2596.182.8.129 to 96.182.8.25496.182.8.255126
1996.182.9.0/2596.182.9.1 to 96.182.9.12696.182.9.127126
2096.182.9.128/2596.182.9.129 to 96.182.9.25496.182.9.255126
2196.182.10.0/2596.182.10.1 to 96.182.10.12696.182.10.127126
2296.182.10.128/2596.182.10.129 to 96.182.10.25496.182.10.255126
2396.182.11.0/2596.182.11.1 to 96.182.11.12696.182.11.127126
2496.182.11.128/2596.182.11.129 to 96.182.11.25496.182.11.255126
2596.182.12.0/2596.182.12.1 to 96.182.12.12696.182.12.127126
2696.182.12.128/2596.182.12.129 to 96.182.12.25496.182.12.255126
2796.182.13.0/2596.182.13.1 to 96.182.13.12696.182.13.127126
2896.182.13.128/2596.182.13.129 to 96.182.13.25496.182.13.255126
2996.182.14.0/2596.182.14.1 to 96.182.14.12696.182.14.127126
3096.182.14.128/2596.182.14.129 to 96.182.14.25496.182.14.255126
3196.182.15.0/2596.182.15.1 to 96.182.15.12696.182.15.127126
3296.182.15.128/2596.182.15.129 to 96.182.15.25496.182.15.255126
3396.182.16.0/2596.182.16.1 to 96.182.16.12696.182.16.127126
3496.182.16.128/2596.182.16.129 to 96.182.16.25496.182.16.255126
3596.182.17.0/2596.182.17.1 to 96.182.17.12696.182.17.127126
3696.182.17.128/2596.182.17.129 to 96.182.17.25496.182.17.255126
3796.182.18.0/2596.182.18.1 to 96.182.18.12696.182.18.127126
3896.182.18.128/2596.182.18.129 to 96.182.18.25496.182.18.255126
3996.182.19.0/2596.182.19.1 to 96.182.19.12696.182.19.127126
4096.182.19.128/2596.182.19.129 to 96.182.19.25496.182.19.255126
4196.182.20.0/2596.182.20.1 to 96.182.20.12696.182.20.127126
4296.182.20.128/2596.182.20.129 to 96.182.20.25496.182.20.255126
4396.182.21.0/2596.182.21.1 to 96.182.21.12696.182.21.127126
4496.182.21.128/2596.182.21.129 to 96.182.21.25496.182.21.255126
4596.182.22.0/2596.182.22.1 to 96.182.22.12696.182.22.127126
4696.182.22.128/2596.182.22.129 to 96.182.22.25496.182.22.255126
4796.182.23.0/2596.182.23.1 to 96.182.23.12696.182.23.127126
4896.182.23.128/2596.182.23.129 to 96.182.23.25496.182.23.255126
4996.182.24.0/2596.182.24.1 to 96.182.24.12696.182.24.127126
5096.182.24.128/2596.182.24.129 to 96.182.24.25496.182.24.255126
5196.182.25.0/2596.182.25.1 to 96.182.25.12696.182.25.127126
5296.182.25.128/2596.182.25.129 to 96.182.25.25496.182.25.255126
5396.182.26.0/2596.182.26.1 to 96.182.26.12696.182.26.127126
5496.182.26.128/2596.182.26.129 to 96.182.26.25496.182.26.255126
5596.182.27.0/2596.182.27.1 to 96.182.27.12696.182.27.127126
5696.182.27.128/2596.182.27.129 to 96.182.27.25496.182.27.255126
5796.182.28.0/2596.182.28.1 to 96.182.28.12696.182.28.127126
5896.182.28.128/2596.182.28.129 to 96.182.28.25496.182.28.255126
5996.182.29.0/2596.182.29.1 to 96.182.29.12696.182.29.127126
6096.182.29.128/2596.182.29.129 to 96.182.29.25496.182.29.255126
6196.182.30.0/2596.182.30.1 to 96.182.30.12696.182.30.127126
6296.182.30.128/2596.182.30.129 to 96.182.30.25496.182.30.255126
6396.182.31.0/2596.182.31.1 to 96.182.31.12696.182.31.127126
6496.182.31.128/2596.182.31.129 to 96.182.31.25496.182.31.255126
6596.182.32.0/2596.182.32.1 to 96.182.32.12696.182.32.127126
6696.182.32.128/2596.182.32.129 to 96.182.32.25496.182.32.255126
6796.182.33.0/2596.182.33.1 to 96.182.33.12696.182.33.127126
6896.182.33.128/2596.182.33.129 to 96.182.33.25496.182.33.255126
6996.182.34.0/2596.182.34.1 to 96.182.34.12696.182.34.127126
7096.182.34.128/2596.182.34.129 to 96.182.34.25496.182.34.255126
7196.182.35.0/2596.182.35.1 to 96.182.35.12696.182.35.127126
7296.182.35.128/2596.182.35.129 to 96.182.35.25496.182.35.255126
7396.182.36.0/2596.182.36.1 to 96.182.36.12696.182.36.127126
7496.182.36.128/2596.182.36.129 to 96.182.36.25496.182.36.255126
7596.182.37.0/2596.182.37.1 to 96.182.37.12696.182.37.127126
7696.182.37.128/2596.182.37.129 to 96.182.37.25496.182.37.255126
7796.182.38.0/2596.182.38.1 to 96.182.38.12696.182.38.127126
7896.182.38.128/2596.182.38.129 to 96.182.38.25496.182.38.255126
7996.182.39.0/2596.182.39.1 to 96.182.39.12696.182.39.127126
8096.182.39.128/2596.182.39.129 to 96.182.39.25496.182.39.255126
8196.182.40.0/2596.182.40.1 to 96.182.40.12696.182.40.127126
8296.182.40.128/2596.182.40.129 to 96.182.40.25496.182.40.255126
8396.182.41.0/2596.182.41.1 to 96.182.41.12696.182.41.127126
8496.182.41.128/2596.182.41.129 to 96.182.41.25496.182.41.255126
8596.182.42.0/2596.182.42.1 to 96.182.42.12696.182.42.127126
8696.182.42.128/2596.182.42.129 to 96.182.42.25496.182.42.255126
8796.182.43.0/2596.182.43.1 to 96.182.43.12696.182.43.127126
8896.182.43.128/2596.182.43.129 to 96.182.43.25496.182.43.255126
8996.182.44.0/2596.182.44.1 to 96.182.44.12696.182.44.127126
9096.182.44.128/2596.182.44.129 to 96.182.44.25496.182.44.255126
9196.182.45.0/2596.182.45.1 to 96.182.45.12696.182.45.127126
9296.182.45.128/2596.182.45.129 to 96.182.45.25496.182.45.255126
9396.182.46.0/2596.182.46.1 to 96.182.46.12696.182.46.127126
9496.182.46.128/2596.182.46.129 to 96.182.46.25496.182.46.255126
9596.182.47.0/2596.182.47.1 to 96.182.47.12696.182.47.127126
9696.182.47.128/2596.182.47.129 to 96.182.47.25496.182.47.255126
9796.182.48.0/2596.182.48.1 to 96.182.48.12696.182.48.127126
9896.182.48.128/2596.182.48.129 to 96.182.48.25496.182.48.255126
9996.182.49.0/2596.182.49.1 to 96.182.49.12696.182.49.127126
10096.182.49.128/2596.182.49.129 to 96.182.49.25496.182.49.255126
10196.182.50.0/2596.182.50.1 to 96.182.50.12696.182.50.127126
10296.182.50.128/2596.182.50.129 to 96.182.50.25496.182.50.255126
10396.182.51.0/2596.182.51.1 to 96.182.51.12696.182.51.127126
10496.182.51.128/2596.182.51.129 to 96.182.51.25496.182.51.255126
10596.182.52.0/2596.182.52.1 to 96.182.52.12696.182.52.127126
10696.182.52.128/2596.182.52.129 to 96.182.52.25496.182.52.255126
10796.182.53.0/2596.182.53.1 to 96.182.53.12696.182.53.127126
10896.182.53.128/2596.182.53.129 to 96.182.53.25496.182.53.255126
10996.182.54.0/2596.182.54.1 to 96.182.54.12696.182.54.127126
11096.182.54.128/2596.182.54.129 to 96.182.54.25496.182.54.255126
11196.182.55.0/2596.182.55.1 to 96.182.55.12696.182.55.127126
11296.182.55.128/2596.182.55.129 to 96.182.55.25496.182.55.255126
11396.182.56.0/2596.182.56.1 to 96.182.56.12696.182.56.127126
11496.182.56.128/2596.182.56.129 to 96.182.56.25496.182.56.255126
11596.182.57.0/2596.182.57.1 to 96.182.57.12696.182.57.127126
11696.182.57.128/2596.182.57.129 to 96.182.57.25496.182.57.255126
11796.182.58.0/2596.182.58.1 to 96.182.58.12696.182.58.127126
11896.182.58.128/2596.182.58.129 to 96.182.58.25496.182.58.255126
11996.182.59.0/2596.182.59.1 to 96.182.59.12696.182.59.127126
12096.182.59.128/2596.182.59.129 to 96.182.59.25496.182.59.255126
12196.182.60.0/2596.182.60.1 to 96.182.60.12696.182.60.127126
12296.182.60.128/2596.182.60.129 to 96.182.60.25496.182.60.255126
12396.182.61.0/2596.182.61.1 to 96.182.61.12696.182.61.127126
12496.182.61.128/2596.182.61.129 to 96.182.61.25496.182.61.255126
12596.182.62.0/2596.182.62.1 to 96.182.62.12696.182.62.127126
12696.182.62.128/2596.182.62.129 to 96.182.62.25496.182.62.255126
12796.182.63.0/2596.182.63.1 to 96.182.63.12696.182.63.127126
12896.182.63.128/2596.182.63.129 to 96.182.63.25496.182.63.255126
12996.182.64.0/2596.182.64.1 to 96.182.64.12696.182.64.127126
13096.182.64.128/2596.182.64.129 to 96.182.64.25496.182.64.255126
13196.182.65.0/2596.182.65.1 to 96.182.65.12696.182.65.127126
13296.182.65.128/2596.182.65.129 to 96.182.65.25496.182.65.255126
13396.182.66.0/2596.182.66.1 to 96.182.66.12696.182.66.127126
13496.182.66.128/2596.182.66.129 to 96.182.66.25496.182.66.255126
13596.182.67.0/2596.182.67.1 to 96.182.67.12696.182.67.127126
13696.182.67.128/2596.182.67.129 to 96.182.67.25496.182.67.255126
13796.182.68.0/2596.182.68.1 to 96.182.68.12696.182.68.127126
13896.182.68.128/2596.182.68.129 to 96.182.68.25496.182.68.255126
13996.182.69.0/2596.182.69.1 to 96.182.69.12696.182.69.127126
14096.182.69.128/2596.182.69.129 to 96.182.69.25496.182.69.255126
14196.182.70.0/2596.182.70.1 to 96.182.70.12696.182.70.127126
14296.182.70.128/2596.182.70.129 to 96.182.70.25496.182.70.255126
14396.182.71.0/2596.182.71.1 to 96.182.71.12696.182.71.127126
14496.182.71.128/2596.182.71.129 to 96.182.71.25496.182.71.255126
14596.182.72.0/2596.182.72.1 to 96.182.72.12696.182.72.127126
14696.182.72.128/2596.182.72.129 to 96.182.72.25496.182.72.255126
14796.182.73.0/2596.182.73.1 to 96.182.73.12696.182.73.127126
14896.182.73.128/2596.182.73.129 to 96.182.73.25496.182.73.255126
14996.182.74.0/2596.182.74.1 to 96.182.74.12696.182.74.127126
15096.182.74.128/2596.182.74.129 to 96.182.74.25496.182.74.255126
15196.182.75.0/2596.182.75.1 to 96.182.75.12696.182.75.127126
15296.182.75.128/2596.182.75.129 to 96.182.75.25496.182.75.255126
15396.182.76.0/2596.182.76.1 to 96.182.76.12696.182.76.127126
15496.182.76.128/2596.182.76.129 to 96.182.76.25496.182.76.255126
15596.182.77.0/2596.182.77.1 to 96.182.77.12696.182.77.127126
15696.182.77.128/2596.182.77.129 to 96.182.77.25496.182.77.255126
15796.182.78.0/2596.182.78.1 to 96.182.78.12696.182.78.127126
15896.182.78.128/2596.182.78.129 to 96.182.78.25496.182.78.255126
15996.182.79.0/2596.182.79.1 to 96.182.79.12696.182.79.127126
16096.182.79.128/2596.182.79.129 to 96.182.79.25496.182.79.255126
16196.182.80.0/2596.182.80.1 to 96.182.80.12696.182.80.127126
16296.182.80.128/2596.182.80.129 to 96.182.80.25496.182.80.255126
16396.182.81.0/2596.182.81.1 to 96.182.81.12696.182.81.127126
16496.182.81.128/2596.182.81.129 to 96.182.81.25496.182.81.255126
16596.182.82.0/2596.182.82.1 to 96.182.82.12696.182.82.127126
16696.182.82.128/2596.182.82.129 to 96.182.82.25496.182.82.255126
16796.182.83.0/2596.182.83.1 to 96.182.83.12696.182.83.127126
16896.182.83.128/2596.182.83.129 to 96.182.83.25496.182.83.255126
16996.182.84.0/2596.182.84.1 to 96.182.84.12696.182.84.127126
17096.182.84.128/2596.182.84.129 to 96.182.84.25496.182.84.255126
17196.182.85.0/2596.182.85.1 to 96.182.85.12696.182.85.127126
17296.182.85.128/2596.182.85.129 to 96.182.85.25496.182.85.255126
17396.182.86.0/2596.182.86.1 to 96.182.86.12696.182.86.127126
17496.182.86.128/2596.182.86.129 to 96.182.86.25496.182.86.255126
17596.182.87.0/2596.182.87.1 to 96.182.87.12696.182.87.127126
17696.182.87.128/2596.182.87.129 to 96.182.87.25496.182.87.255126
17796.182.88.0/2596.182.88.1 to 96.182.88.12696.182.88.127126
17896.182.88.128/2596.182.88.129 to 96.182.88.25496.182.88.255126
17996.182.89.0/2596.182.89.1 to 96.182.89.12696.182.89.127126
18096.182.89.128/2596.182.89.129 to 96.182.89.25496.182.89.255126
18196.182.90.0/2596.182.90.1 to 96.182.90.12696.182.90.127126
18296.182.90.128/2596.182.90.129 to 96.182.90.25496.182.90.255126
18396.182.91.0/2596.182.91.1 to 96.182.91.12696.182.91.127126
18496.182.91.128/2596.182.91.129 to 96.182.91.25496.182.91.255126
18596.182.92.0/2596.182.92.1 to 96.182.92.12696.182.92.127126
18696.182.92.128/2596.182.92.129 to 96.182.92.25496.182.92.255126
18796.182.93.0/2596.182.93.1 to 96.182.93.12696.182.93.127126
18896.182.93.128/2596.182.93.129 to 96.182.93.25496.182.93.255126
18996.182.94.0/2596.182.94.1 to 96.182.94.12696.182.94.127126
19096.182.94.128/2596.182.94.129 to 96.182.94.25496.182.94.255126
19196.182.95.0/2596.182.95.1 to 96.182.95.12696.182.95.127126
19296.182.95.128/2596.182.95.129 to 96.182.95.25496.182.95.255126
19396.182.96.0/2596.182.96.1 to 96.182.96.12696.182.96.127126
19496.182.96.128/2596.182.96.129 to 96.182.96.25496.182.96.255126
19596.182.97.0/2596.182.97.1 to 96.182.97.12696.182.97.127126
19696.182.97.128/2596.182.97.129 to 96.182.97.25496.182.97.255126
19796.182.98.0/2596.182.98.1 to 96.182.98.12696.182.98.127126
19896.182.98.128/2596.182.98.129 to 96.182.98.25496.182.98.255126
19996.182.99.0/2596.182.99.1 to 96.182.99.12696.182.99.127126
20096.182.99.128/2596.182.99.129 to 96.182.99.25496.182.99.255126
20196.182.100.0/2596.182.100.1 to 96.182.100.12696.182.100.127126
20296.182.100.128/2596.182.100.129 to 96.182.100.25496.182.100.255126
20396.182.101.0/2596.182.101.1 to 96.182.101.12696.182.101.127126
20496.182.101.128/2596.182.101.129 to 96.182.101.25496.182.101.255126
20596.182.102.0/2596.182.102.1 to 96.182.102.12696.182.102.127126
20696.182.102.128/2596.182.102.129 to 96.182.102.25496.182.102.255126
20796.182.103.0/2596.182.103.1 to 96.182.103.12696.182.103.127126
20896.182.103.128/2596.182.103.129 to 96.182.103.25496.182.103.255126
20996.182.104.0/2596.182.104.1 to 96.182.104.12696.182.104.127126
21096.182.104.128/2596.182.104.129 to 96.182.104.25496.182.104.255126
21196.182.105.0/2596.182.105.1 to 96.182.105.12696.182.105.127126
21296.182.105.128/2596.182.105.129 to 96.182.105.25496.182.105.255126
21396.182.106.0/2596.182.106.1 to 96.182.106.12696.182.106.127126
21496.182.106.128/2596.182.106.129 to 96.182.106.25496.182.106.255126
21596.182.107.0/2596.182.107.1 to 96.182.107.12696.182.107.127126
21696.182.107.128/2596.182.107.129 to 96.182.107.25496.182.107.255126
21796.182.108.0/2596.182.108.1 to 96.182.108.12696.182.108.127126
21896.182.108.128/2596.182.108.129 to 96.182.108.25496.182.108.255126
21996.182.109.0/2596.182.109.1 to 96.182.109.12696.182.109.127126
22096.182.109.128/2596.182.109.129 to 96.182.109.25496.182.109.255126
22196.182.110.0/2596.182.110.1 to 96.182.110.12696.182.110.127126
22296.182.110.128/2596.182.110.129 to 96.182.110.25496.182.110.255126
22396.182.111.0/2596.182.111.1 to 96.182.111.12696.182.111.127126
22496.182.111.128/2596.182.111.129 to 96.182.111.25496.182.111.255126
22596.182.112.0/2596.182.112.1 to 96.182.112.12696.182.112.127126
22696.182.112.128/2596.182.112.129 to 96.182.112.25496.182.112.255126
22796.182.113.0/2596.182.113.1 to 96.182.113.12696.182.113.127126
22896.182.113.128/2596.182.113.129 to 96.182.113.25496.182.113.255126
22996.182.114.0/2596.182.114.1 to 96.182.114.12696.182.114.127126
23096.182.114.128/2596.182.114.129 to 96.182.114.25496.182.114.255126
23196.182.115.0/2596.182.115.1 to 96.182.115.12696.182.115.127126
23296.182.115.128/2596.182.115.129 to 96.182.115.25496.182.115.255126
23396.182.116.0/2596.182.116.1 to 96.182.116.12696.182.116.127126
23496.182.116.128/2596.182.116.129 to 96.182.116.25496.182.116.255126
23596.182.117.0/2596.182.117.1 to 96.182.117.12696.182.117.127126
23696.182.117.128/2596.182.117.129 to 96.182.117.25496.182.117.255126
23796.182.118.0/2596.182.118.1 to 96.182.118.12696.182.118.127126
23896.182.118.128/2596.182.118.129 to 96.182.118.25496.182.118.255126
23996.182.119.0/2596.182.119.1 to 96.182.119.12696.182.119.127126
24096.182.119.128/2596.182.119.129 to 96.182.119.25496.182.119.255126
24196.182.120.0/2596.182.120.1 to 96.182.120.12696.182.120.127126
24296.182.120.128/2596.182.120.129 to 96.182.120.25496.182.120.255126
24396.182.121.0/2596.182.121.1 to 96.182.121.12696.182.121.127126
24496.182.121.128/2596.182.121.129 to 96.182.121.25496.182.121.255126
24596.182.122.0/2596.182.122.1 to 96.182.122.12696.182.122.127126
24696.182.122.128/2596.182.122.129 to 96.182.122.25496.182.122.255126
24796.182.123.0/2596.182.123.1 to 96.182.123.12696.182.123.127126
24896.182.123.128/2596.182.123.129 to 96.182.123.25496.182.123.255126
24996.182.124.0/2596.182.124.1 to 96.182.124.12696.182.124.127126
25096.182.124.128/2596.182.124.129 to 96.182.124.25496.182.124.255126
25196.182.125.0/2596.182.125.1 to 96.182.125.12696.182.125.127126
25296.182.125.128/2596.182.125.129 to 96.182.125.25496.182.125.255126
25396.182.126.0/2596.182.126.1 to 96.182.126.12696.182.126.127126
25496.182.126.128/2596.182.126.129 to 96.182.126.25496.182.126.255126
25596.182.127.0/2596.182.127.1 to 96.182.127.12696.182.127.127126
25696.182.127.128/2596.182.127.129 to 96.182.127.25496.182.127.255126

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.