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.

Network89.3.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
89.3.0.0
Broadcast address
89.3.63.255
First usable
89.3.0.1
Last usable
89.3.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 59030000 · Integer 1493368832 to 1493385215
Reverse DNS zones
0.3.89.in-addr.arpa
1.3.89.in-addr.arpa
2.3.89.in-addr.arpa
3.3.89.in-addr.arpa
4.3.89.in-addr.arpa
5.3.89.in-addr.arpa
6.3.89.in-addr.arpa
7.3.89.in-addr.arpa
8.3.89.in-addr.arpa
9.3.89.in-addr.arpa
10.3.89.in-addr.arpa
11.3.89.in-addr.arpa
12.3.89.in-addr.arpa
13.3.89.in-addr.arpa
14.3.89.in-addr.arpa
15.3.89.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011001.00000011.00000000.0000000089.3.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01011001.00000011.00000000.0000000089.3.0.0
Broadcast01011001.00000011.00111111.1111111189.3.63.255
Split into smaller subnets/27

89.3.0.0/18 makes 512 subnets of /27; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
189.3.0.0/2789.3.0.1 to 89.3.0.3089.3.0.3130
289.3.0.32/2789.3.0.33 to 89.3.0.6289.3.0.6330
389.3.0.64/2789.3.0.65 to 89.3.0.9489.3.0.9530
489.3.0.96/2789.3.0.97 to 89.3.0.12689.3.0.12730
589.3.0.128/2789.3.0.129 to 89.3.0.15889.3.0.15930
689.3.0.160/2789.3.0.161 to 89.3.0.19089.3.0.19130
789.3.0.192/2789.3.0.193 to 89.3.0.22289.3.0.22330
889.3.0.224/2789.3.0.225 to 89.3.0.25489.3.0.25530
989.3.1.0/2789.3.1.1 to 89.3.1.3089.3.1.3130
1089.3.1.32/2789.3.1.33 to 89.3.1.6289.3.1.6330
1189.3.1.64/2789.3.1.65 to 89.3.1.9489.3.1.9530
1289.3.1.96/2789.3.1.97 to 89.3.1.12689.3.1.12730
1389.3.1.128/2789.3.1.129 to 89.3.1.15889.3.1.15930
1489.3.1.160/2789.3.1.161 to 89.3.1.19089.3.1.19130
1589.3.1.192/2789.3.1.193 to 89.3.1.22289.3.1.22330
1689.3.1.224/2789.3.1.225 to 89.3.1.25489.3.1.25530
1789.3.2.0/2789.3.2.1 to 89.3.2.3089.3.2.3130
1889.3.2.32/2789.3.2.33 to 89.3.2.6289.3.2.6330
1989.3.2.64/2789.3.2.65 to 89.3.2.9489.3.2.9530
2089.3.2.96/2789.3.2.97 to 89.3.2.12689.3.2.12730
2189.3.2.128/2789.3.2.129 to 89.3.2.15889.3.2.15930
2289.3.2.160/2789.3.2.161 to 89.3.2.19089.3.2.19130
2389.3.2.192/2789.3.2.193 to 89.3.2.22289.3.2.22330
2489.3.2.224/2789.3.2.225 to 89.3.2.25489.3.2.25530
2589.3.3.0/2789.3.3.1 to 89.3.3.3089.3.3.3130
2689.3.3.32/2789.3.3.33 to 89.3.3.6289.3.3.6330
2789.3.3.64/2789.3.3.65 to 89.3.3.9489.3.3.9530
2889.3.3.96/2789.3.3.97 to 89.3.3.12689.3.3.12730
2989.3.3.128/2789.3.3.129 to 89.3.3.15889.3.3.15930
3089.3.3.160/2789.3.3.161 to 89.3.3.19089.3.3.19130
3189.3.3.192/2789.3.3.193 to 89.3.3.22289.3.3.22330
3289.3.3.224/2789.3.3.225 to 89.3.3.25489.3.3.25530
3389.3.4.0/2789.3.4.1 to 89.3.4.3089.3.4.3130
3489.3.4.32/2789.3.4.33 to 89.3.4.6289.3.4.6330
3589.3.4.64/2789.3.4.65 to 89.3.4.9489.3.4.9530
3689.3.4.96/2789.3.4.97 to 89.3.4.12689.3.4.12730
3789.3.4.128/2789.3.4.129 to 89.3.4.15889.3.4.15930
3889.3.4.160/2789.3.4.161 to 89.3.4.19089.3.4.19130
3989.3.4.192/2789.3.4.193 to 89.3.4.22289.3.4.22330
4089.3.4.224/2789.3.4.225 to 89.3.4.25489.3.4.25530
4189.3.5.0/2789.3.5.1 to 89.3.5.3089.3.5.3130
4289.3.5.32/2789.3.5.33 to 89.3.5.6289.3.5.6330
4389.3.5.64/2789.3.5.65 to 89.3.5.9489.3.5.9530
4489.3.5.96/2789.3.5.97 to 89.3.5.12689.3.5.12730
4589.3.5.128/2789.3.5.129 to 89.3.5.15889.3.5.15930
4689.3.5.160/2789.3.5.161 to 89.3.5.19089.3.5.19130
4789.3.5.192/2789.3.5.193 to 89.3.5.22289.3.5.22330
4889.3.5.224/2789.3.5.225 to 89.3.5.25489.3.5.25530
4989.3.6.0/2789.3.6.1 to 89.3.6.3089.3.6.3130
5089.3.6.32/2789.3.6.33 to 89.3.6.6289.3.6.6330
5189.3.6.64/2789.3.6.65 to 89.3.6.9489.3.6.9530
5289.3.6.96/2789.3.6.97 to 89.3.6.12689.3.6.12730
5389.3.6.128/2789.3.6.129 to 89.3.6.15889.3.6.15930
5489.3.6.160/2789.3.6.161 to 89.3.6.19089.3.6.19130
5589.3.6.192/2789.3.6.193 to 89.3.6.22289.3.6.22330
5689.3.6.224/2789.3.6.225 to 89.3.6.25489.3.6.25530
5789.3.7.0/2789.3.7.1 to 89.3.7.3089.3.7.3130
5889.3.7.32/2789.3.7.33 to 89.3.7.6289.3.7.6330
5989.3.7.64/2789.3.7.65 to 89.3.7.9489.3.7.9530
6089.3.7.96/2789.3.7.97 to 89.3.7.12689.3.7.12730
6189.3.7.128/2789.3.7.129 to 89.3.7.15889.3.7.15930
6289.3.7.160/2789.3.7.161 to 89.3.7.19089.3.7.19130
6389.3.7.192/2789.3.7.193 to 89.3.7.22289.3.7.22330
6489.3.7.224/2789.3.7.225 to 89.3.7.25489.3.7.25530
6589.3.8.0/2789.3.8.1 to 89.3.8.3089.3.8.3130
6689.3.8.32/2789.3.8.33 to 89.3.8.6289.3.8.6330
6789.3.8.64/2789.3.8.65 to 89.3.8.9489.3.8.9530
6889.3.8.96/2789.3.8.97 to 89.3.8.12689.3.8.12730
6989.3.8.128/2789.3.8.129 to 89.3.8.15889.3.8.15930
7089.3.8.160/2789.3.8.161 to 89.3.8.19089.3.8.19130
7189.3.8.192/2789.3.8.193 to 89.3.8.22289.3.8.22330
7289.3.8.224/2789.3.8.225 to 89.3.8.25489.3.8.25530
7389.3.9.0/2789.3.9.1 to 89.3.9.3089.3.9.3130
7489.3.9.32/2789.3.9.33 to 89.3.9.6289.3.9.6330
7589.3.9.64/2789.3.9.65 to 89.3.9.9489.3.9.9530
7689.3.9.96/2789.3.9.97 to 89.3.9.12689.3.9.12730
7789.3.9.128/2789.3.9.129 to 89.3.9.15889.3.9.15930
7889.3.9.160/2789.3.9.161 to 89.3.9.19089.3.9.19130
7989.3.9.192/2789.3.9.193 to 89.3.9.22289.3.9.22330
8089.3.9.224/2789.3.9.225 to 89.3.9.25489.3.9.25530
8189.3.10.0/2789.3.10.1 to 89.3.10.3089.3.10.3130
8289.3.10.32/2789.3.10.33 to 89.3.10.6289.3.10.6330
8389.3.10.64/2789.3.10.65 to 89.3.10.9489.3.10.9530
8489.3.10.96/2789.3.10.97 to 89.3.10.12689.3.10.12730
8589.3.10.128/2789.3.10.129 to 89.3.10.15889.3.10.15930
8689.3.10.160/2789.3.10.161 to 89.3.10.19089.3.10.19130
8789.3.10.192/2789.3.10.193 to 89.3.10.22289.3.10.22330
8889.3.10.224/2789.3.10.225 to 89.3.10.25489.3.10.25530
8989.3.11.0/2789.3.11.1 to 89.3.11.3089.3.11.3130
9089.3.11.32/2789.3.11.33 to 89.3.11.6289.3.11.6330
9189.3.11.64/2789.3.11.65 to 89.3.11.9489.3.11.9530
9289.3.11.96/2789.3.11.97 to 89.3.11.12689.3.11.12730
9389.3.11.128/2789.3.11.129 to 89.3.11.15889.3.11.15930
9489.3.11.160/2789.3.11.161 to 89.3.11.19089.3.11.19130
9589.3.11.192/2789.3.11.193 to 89.3.11.22289.3.11.22330
9689.3.11.224/2789.3.11.225 to 89.3.11.25489.3.11.25530
9789.3.12.0/2789.3.12.1 to 89.3.12.3089.3.12.3130
9889.3.12.32/2789.3.12.33 to 89.3.12.6289.3.12.6330
9989.3.12.64/2789.3.12.65 to 89.3.12.9489.3.12.9530
10089.3.12.96/2789.3.12.97 to 89.3.12.12689.3.12.12730
10189.3.12.128/2789.3.12.129 to 89.3.12.15889.3.12.15930
10289.3.12.160/2789.3.12.161 to 89.3.12.19089.3.12.19130
10389.3.12.192/2789.3.12.193 to 89.3.12.22289.3.12.22330
10489.3.12.224/2789.3.12.225 to 89.3.12.25489.3.12.25530
10589.3.13.0/2789.3.13.1 to 89.3.13.3089.3.13.3130
10689.3.13.32/2789.3.13.33 to 89.3.13.6289.3.13.6330
10789.3.13.64/2789.3.13.65 to 89.3.13.9489.3.13.9530
10889.3.13.96/2789.3.13.97 to 89.3.13.12689.3.13.12730
10989.3.13.128/2789.3.13.129 to 89.3.13.15889.3.13.15930
11089.3.13.160/2789.3.13.161 to 89.3.13.19089.3.13.19130
11189.3.13.192/2789.3.13.193 to 89.3.13.22289.3.13.22330
11289.3.13.224/2789.3.13.225 to 89.3.13.25489.3.13.25530
11389.3.14.0/2789.3.14.1 to 89.3.14.3089.3.14.3130
11489.3.14.32/2789.3.14.33 to 89.3.14.6289.3.14.6330
11589.3.14.64/2789.3.14.65 to 89.3.14.9489.3.14.9530
11689.3.14.96/2789.3.14.97 to 89.3.14.12689.3.14.12730
11789.3.14.128/2789.3.14.129 to 89.3.14.15889.3.14.15930
11889.3.14.160/2789.3.14.161 to 89.3.14.19089.3.14.19130
11989.3.14.192/2789.3.14.193 to 89.3.14.22289.3.14.22330
12089.3.14.224/2789.3.14.225 to 89.3.14.25489.3.14.25530
12189.3.15.0/2789.3.15.1 to 89.3.15.3089.3.15.3130
12289.3.15.32/2789.3.15.33 to 89.3.15.6289.3.15.6330
12389.3.15.64/2789.3.15.65 to 89.3.15.9489.3.15.9530
12489.3.15.96/2789.3.15.97 to 89.3.15.12689.3.15.12730
12589.3.15.128/2789.3.15.129 to 89.3.15.15889.3.15.15930
12689.3.15.160/2789.3.15.161 to 89.3.15.19089.3.15.19130
12789.3.15.192/2789.3.15.193 to 89.3.15.22289.3.15.22330
12889.3.15.224/2789.3.15.225 to 89.3.15.25489.3.15.25530
12989.3.16.0/2789.3.16.1 to 89.3.16.3089.3.16.3130
13089.3.16.32/2789.3.16.33 to 89.3.16.6289.3.16.6330
13189.3.16.64/2789.3.16.65 to 89.3.16.9489.3.16.9530
13289.3.16.96/2789.3.16.97 to 89.3.16.12689.3.16.12730
13389.3.16.128/2789.3.16.129 to 89.3.16.15889.3.16.15930
13489.3.16.160/2789.3.16.161 to 89.3.16.19089.3.16.19130
13589.3.16.192/2789.3.16.193 to 89.3.16.22289.3.16.22330
13689.3.16.224/2789.3.16.225 to 89.3.16.25489.3.16.25530
13789.3.17.0/2789.3.17.1 to 89.3.17.3089.3.17.3130
13889.3.17.32/2789.3.17.33 to 89.3.17.6289.3.17.6330
13989.3.17.64/2789.3.17.65 to 89.3.17.9489.3.17.9530
14089.3.17.96/2789.3.17.97 to 89.3.17.12689.3.17.12730
14189.3.17.128/2789.3.17.129 to 89.3.17.15889.3.17.15930
14289.3.17.160/2789.3.17.161 to 89.3.17.19089.3.17.19130
14389.3.17.192/2789.3.17.193 to 89.3.17.22289.3.17.22330
14489.3.17.224/2789.3.17.225 to 89.3.17.25489.3.17.25530
14589.3.18.0/2789.3.18.1 to 89.3.18.3089.3.18.3130
14689.3.18.32/2789.3.18.33 to 89.3.18.6289.3.18.6330
14789.3.18.64/2789.3.18.65 to 89.3.18.9489.3.18.9530
14889.3.18.96/2789.3.18.97 to 89.3.18.12689.3.18.12730
14989.3.18.128/2789.3.18.129 to 89.3.18.15889.3.18.15930
15089.3.18.160/2789.3.18.161 to 89.3.18.19089.3.18.19130
15189.3.18.192/2789.3.18.193 to 89.3.18.22289.3.18.22330
15289.3.18.224/2789.3.18.225 to 89.3.18.25489.3.18.25530
15389.3.19.0/2789.3.19.1 to 89.3.19.3089.3.19.3130
15489.3.19.32/2789.3.19.33 to 89.3.19.6289.3.19.6330
15589.3.19.64/2789.3.19.65 to 89.3.19.9489.3.19.9530
15689.3.19.96/2789.3.19.97 to 89.3.19.12689.3.19.12730
15789.3.19.128/2789.3.19.129 to 89.3.19.15889.3.19.15930
15889.3.19.160/2789.3.19.161 to 89.3.19.19089.3.19.19130
15989.3.19.192/2789.3.19.193 to 89.3.19.22289.3.19.22330
16089.3.19.224/2789.3.19.225 to 89.3.19.25489.3.19.25530
16189.3.20.0/2789.3.20.1 to 89.3.20.3089.3.20.3130
16289.3.20.32/2789.3.20.33 to 89.3.20.6289.3.20.6330
16389.3.20.64/2789.3.20.65 to 89.3.20.9489.3.20.9530
16489.3.20.96/2789.3.20.97 to 89.3.20.12689.3.20.12730
16589.3.20.128/2789.3.20.129 to 89.3.20.15889.3.20.15930
16689.3.20.160/2789.3.20.161 to 89.3.20.19089.3.20.19130
16789.3.20.192/2789.3.20.193 to 89.3.20.22289.3.20.22330
16889.3.20.224/2789.3.20.225 to 89.3.20.25489.3.20.25530
16989.3.21.0/2789.3.21.1 to 89.3.21.3089.3.21.3130
17089.3.21.32/2789.3.21.33 to 89.3.21.6289.3.21.6330
17189.3.21.64/2789.3.21.65 to 89.3.21.9489.3.21.9530
17289.3.21.96/2789.3.21.97 to 89.3.21.12689.3.21.12730
17389.3.21.128/2789.3.21.129 to 89.3.21.15889.3.21.15930
17489.3.21.160/2789.3.21.161 to 89.3.21.19089.3.21.19130
17589.3.21.192/2789.3.21.193 to 89.3.21.22289.3.21.22330
17689.3.21.224/2789.3.21.225 to 89.3.21.25489.3.21.25530
17789.3.22.0/2789.3.22.1 to 89.3.22.3089.3.22.3130
17889.3.22.32/2789.3.22.33 to 89.3.22.6289.3.22.6330
17989.3.22.64/2789.3.22.65 to 89.3.22.9489.3.22.9530
18089.3.22.96/2789.3.22.97 to 89.3.22.12689.3.22.12730
18189.3.22.128/2789.3.22.129 to 89.3.22.15889.3.22.15930
18289.3.22.160/2789.3.22.161 to 89.3.22.19089.3.22.19130
18389.3.22.192/2789.3.22.193 to 89.3.22.22289.3.22.22330
18489.3.22.224/2789.3.22.225 to 89.3.22.25489.3.22.25530
18589.3.23.0/2789.3.23.1 to 89.3.23.3089.3.23.3130
18689.3.23.32/2789.3.23.33 to 89.3.23.6289.3.23.6330
18789.3.23.64/2789.3.23.65 to 89.3.23.9489.3.23.9530
18889.3.23.96/2789.3.23.97 to 89.3.23.12689.3.23.12730
18989.3.23.128/2789.3.23.129 to 89.3.23.15889.3.23.15930
19089.3.23.160/2789.3.23.161 to 89.3.23.19089.3.23.19130
19189.3.23.192/2789.3.23.193 to 89.3.23.22289.3.23.22330
19289.3.23.224/2789.3.23.225 to 89.3.23.25489.3.23.25530
19389.3.24.0/2789.3.24.1 to 89.3.24.3089.3.24.3130
19489.3.24.32/2789.3.24.33 to 89.3.24.6289.3.24.6330
19589.3.24.64/2789.3.24.65 to 89.3.24.9489.3.24.9530
19689.3.24.96/2789.3.24.97 to 89.3.24.12689.3.24.12730
19789.3.24.128/2789.3.24.129 to 89.3.24.15889.3.24.15930
19889.3.24.160/2789.3.24.161 to 89.3.24.19089.3.24.19130
19989.3.24.192/2789.3.24.193 to 89.3.24.22289.3.24.22330
20089.3.24.224/2789.3.24.225 to 89.3.24.25489.3.24.25530
20189.3.25.0/2789.3.25.1 to 89.3.25.3089.3.25.3130
20289.3.25.32/2789.3.25.33 to 89.3.25.6289.3.25.6330
20389.3.25.64/2789.3.25.65 to 89.3.25.9489.3.25.9530
20489.3.25.96/2789.3.25.97 to 89.3.25.12689.3.25.12730
20589.3.25.128/2789.3.25.129 to 89.3.25.15889.3.25.15930
20689.3.25.160/2789.3.25.161 to 89.3.25.19089.3.25.19130
20789.3.25.192/2789.3.25.193 to 89.3.25.22289.3.25.22330
20889.3.25.224/2789.3.25.225 to 89.3.25.25489.3.25.25530
20989.3.26.0/2789.3.26.1 to 89.3.26.3089.3.26.3130
21089.3.26.32/2789.3.26.33 to 89.3.26.6289.3.26.6330
21189.3.26.64/2789.3.26.65 to 89.3.26.9489.3.26.9530
21289.3.26.96/2789.3.26.97 to 89.3.26.12689.3.26.12730
21389.3.26.128/2789.3.26.129 to 89.3.26.15889.3.26.15930
21489.3.26.160/2789.3.26.161 to 89.3.26.19089.3.26.19130
21589.3.26.192/2789.3.26.193 to 89.3.26.22289.3.26.22330
21689.3.26.224/2789.3.26.225 to 89.3.26.25489.3.26.25530
21789.3.27.0/2789.3.27.1 to 89.3.27.3089.3.27.3130
21889.3.27.32/2789.3.27.33 to 89.3.27.6289.3.27.6330
21989.3.27.64/2789.3.27.65 to 89.3.27.9489.3.27.9530
22089.3.27.96/2789.3.27.97 to 89.3.27.12689.3.27.12730
22189.3.27.128/2789.3.27.129 to 89.3.27.15889.3.27.15930
22289.3.27.160/2789.3.27.161 to 89.3.27.19089.3.27.19130
22389.3.27.192/2789.3.27.193 to 89.3.27.22289.3.27.22330
22489.3.27.224/2789.3.27.225 to 89.3.27.25489.3.27.25530
22589.3.28.0/2789.3.28.1 to 89.3.28.3089.3.28.3130
22689.3.28.32/2789.3.28.33 to 89.3.28.6289.3.28.6330
22789.3.28.64/2789.3.28.65 to 89.3.28.9489.3.28.9530
22889.3.28.96/2789.3.28.97 to 89.3.28.12689.3.28.12730
22989.3.28.128/2789.3.28.129 to 89.3.28.15889.3.28.15930
23089.3.28.160/2789.3.28.161 to 89.3.28.19089.3.28.19130
23189.3.28.192/2789.3.28.193 to 89.3.28.22289.3.28.22330
23289.3.28.224/2789.3.28.225 to 89.3.28.25489.3.28.25530
23389.3.29.0/2789.3.29.1 to 89.3.29.3089.3.29.3130
23489.3.29.32/2789.3.29.33 to 89.3.29.6289.3.29.6330
23589.3.29.64/2789.3.29.65 to 89.3.29.9489.3.29.9530
23689.3.29.96/2789.3.29.97 to 89.3.29.12689.3.29.12730
23789.3.29.128/2789.3.29.129 to 89.3.29.15889.3.29.15930
23889.3.29.160/2789.3.29.161 to 89.3.29.19089.3.29.19130
23989.3.29.192/2789.3.29.193 to 89.3.29.22289.3.29.22330
24089.3.29.224/2789.3.29.225 to 89.3.29.25489.3.29.25530
24189.3.30.0/2789.3.30.1 to 89.3.30.3089.3.30.3130
24289.3.30.32/2789.3.30.33 to 89.3.30.6289.3.30.6330
24389.3.30.64/2789.3.30.65 to 89.3.30.9489.3.30.9530
24489.3.30.96/2789.3.30.97 to 89.3.30.12689.3.30.12730
24589.3.30.128/2789.3.30.129 to 89.3.30.15889.3.30.15930
24689.3.30.160/2789.3.30.161 to 89.3.30.19089.3.30.19130
24789.3.30.192/2789.3.30.193 to 89.3.30.22289.3.30.22330
24889.3.30.224/2789.3.30.225 to 89.3.30.25489.3.30.25530
24989.3.31.0/2789.3.31.1 to 89.3.31.3089.3.31.3130
25089.3.31.32/2789.3.31.33 to 89.3.31.6289.3.31.6330
25189.3.31.64/2789.3.31.65 to 89.3.31.9489.3.31.9530
25289.3.31.96/2789.3.31.97 to 89.3.31.12689.3.31.12730
25389.3.31.128/2789.3.31.129 to 89.3.31.15889.3.31.15930
25489.3.31.160/2789.3.31.161 to 89.3.31.19089.3.31.19130
25589.3.31.192/2789.3.31.193 to 89.3.31.22289.3.31.22330
25689.3.31.224/2789.3.31.225 to 89.3.31.25489.3.31.25530

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