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.

Network83.2.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
83.2.0.0
Broadcast address
83.2.63.255
First usable
83.2.0.1
Last usable
83.2.63.254
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 53020000 · Integer 1392640000 to 1392656383
Reverse DNS zones
0.2.83.in-addr.arpa
1.2.83.in-addr.arpa
2.2.83.in-addr.arpa
3.2.83.in-addr.arpa
4.2.83.in-addr.arpa
5.2.83.in-addr.arpa
6.2.83.in-addr.arpa
7.2.83.in-addr.arpa
8.2.83.in-addr.arpa
9.2.83.in-addr.arpa
10.2.83.in-addr.arpa
11.2.83.in-addr.arpa
12.2.83.in-addr.arpa
13.2.83.in-addr.arpa
14.2.83.in-addr.arpa
15.2.83.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
Address01010011.00000010.00000000.0000000083.2.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01010011.00000010.00000000.0000000083.2.0.0
Broadcast01010011.00000010.00111111.1111111183.2.63.255
Split into smaller subnets/28

83.2.0.0/18 makes 1,024 subnets of /28; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
183.2.0.0/2883.2.0.1 to 83.2.0.1483.2.0.1514
283.2.0.16/2883.2.0.17 to 83.2.0.3083.2.0.3114
383.2.0.32/2883.2.0.33 to 83.2.0.4683.2.0.4714
483.2.0.48/2883.2.0.49 to 83.2.0.6283.2.0.6314
583.2.0.64/2883.2.0.65 to 83.2.0.7883.2.0.7914
683.2.0.80/2883.2.0.81 to 83.2.0.9483.2.0.9514
783.2.0.96/2883.2.0.97 to 83.2.0.11083.2.0.11114
883.2.0.112/2883.2.0.113 to 83.2.0.12683.2.0.12714
983.2.0.128/2883.2.0.129 to 83.2.0.14283.2.0.14314
1083.2.0.144/2883.2.0.145 to 83.2.0.15883.2.0.15914
1183.2.0.160/2883.2.0.161 to 83.2.0.17483.2.0.17514
1283.2.0.176/2883.2.0.177 to 83.2.0.19083.2.0.19114
1383.2.0.192/2883.2.0.193 to 83.2.0.20683.2.0.20714
1483.2.0.208/2883.2.0.209 to 83.2.0.22283.2.0.22314
1583.2.0.224/2883.2.0.225 to 83.2.0.23883.2.0.23914
1683.2.0.240/2883.2.0.241 to 83.2.0.25483.2.0.25514
1783.2.1.0/2883.2.1.1 to 83.2.1.1483.2.1.1514
1883.2.1.16/2883.2.1.17 to 83.2.1.3083.2.1.3114
1983.2.1.32/2883.2.1.33 to 83.2.1.4683.2.1.4714
2083.2.1.48/2883.2.1.49 to 83.2.1.6283.2.1.6314
2183.2.1.64/2883.2.1.65 to 83.2.1.7883.2.1.7914
2283.2.1.80/2883.2.1.81 to 83.2.1.9483.2.1.9514
2383.2.1.96/2883.2.1.97 to 83.2.1.11083.2.1.11114
2483.2.1.112/2883.2.1.113 to 83.2.1.12683.2.1.12714
2583.2.1.128/2883.2.1.129 to 83.2.1.14283.2.1.14314
2683.2.1.144/2883.2.1.145 to 83.2.1.15883.2.1.15914
2783.2.1.160/2883.2.1.161 to 83.2.1.17483.2.1.17514
2883.2.1.176/2883.2.1.177 to 83.2.1.19083.2.1.19114
2983.2.1.192/2883.2.1.193 to 83.2.1.20683.2.1.20714
3083.2.1.208/2883.2.1.209 to 83.2.1.22283.2.1.22314
3183.2.1.224/2883.2.1.225 to 83.2.1.23883.2.1.23914
3283.2.1.240/2883.2.1.241 to 83.2.1.25483.2.1.25514
3383.2.2.0/2883.2.2.1 to 83.2.2.1483.2.2.1514
3483.2.2.16/2883.2.2.17 to 83.2.2.3083.2.2.3114
3583.2.2.32/2883.2.2.33 to 83.2.2.4683.2.2.4714
3683.2.2.48/2883.2.2.49 to 83.2.2.6283.2.2.6314
3783.2.2.64/2883.2.2.65 to 83.2.2.7883.2.2.7914
3883.2.2.80/2883.2.2.81 to 83.2.2.9483.2.2.9514
3983.2.2.96/2883.2.2.97 to 83.2.2.11083.2.2.11114
4083.2.2.112/2883.2.2.113 to 83.2.2.12683.2.2.12714
4183.2.2.128/2883.2.2.129 to 83.2.2.14283.2.2.14314
4283.2.2.144/2883.2.2.145 to 83.2.2.15883.2.2.15914
4383.2.2.160/2883.2.2.161 to 83.2.2.17483.2.2.17514
4483.2.2.176/2883.2.2.177 to 83.2.2.19083.2.2.19114
4583.2.2.192/2883.2.2.193 to 83.2.2.20683.2.2.20714
4683.2.2.208/2883.2.2.209 to 83.2.2.22283.2.2.22314
4783.2.2.224/2883.2.2.225 to 83.2.2.23883.2.2.23914
4883.2.2.240/2883.2.2.241 to 83.2.2.25483.2.2.25514
4983.2.3.0/2883.2.3.1 to 83.2.3.1483.2.3.1514
5083.2.3.16/2883.2.3.17 to 83.2.3.3083.2.3.3114
5183.2.3.32/2883.2.3.33 to 83.2.3.4683.2.3.4714
5283.2.3.48/2883.2.3.49 to 83.2.3.6283.2.3.6314
5383.2.3.64/2883.2.3.65 to 83.2.3.7883.2.3.7914
5483.2.3.80/2883.2.3.81 to 83.2.3.9483.2.3.9514
5583.2.3.96/2883.2.3.97 to 83.2.3.11083.2.3.11114
5683.2.3.112/2883.2.3.113 to 83.2.3.12683.2.3.12714
5783.2.3.128/2883.2.3.129 to 83.2.3.14283.2.3.14314
5883.2.3.144/2883.2.3.145 to 83.2.3.15883.2.3.15914
5983.2.3.160/2883.2.3.161 to 83.2.3.17483.2.3.17514
6083.2.3.176/2883.2.3.177 to 83.2.3.19083.2.3.19114
6183.2.3.192/2883.2.3.193 to 83.2.3.20683.2.3.20714
6283.2.3.208/2883.2.3.209 to 83.2.3.22283.2.3.22314
6383.2.3.224/2883.2.3.225 to 83.2.3.23883.2.3.23914
6483.2.3.240/2883.2.3.241 to 83.2.3.25483.2.3.25514
6583.2.4.0/2883.2.4.1 to 83.2.4.1483.2.4.1514
6683.2.4.16/2883.2.4.17 to 83.2.4.3083.2.4.3114
6783.2.4.32/2883.2.4.33 to 83.2.4.4683.2.4.4714
6883.2.4.48/2883.2.4.49 to 83.2.4.6283.2.4.6314
6983.2.4.64/2883.2.4.65 to 83.2.4.7883.2.4.7914
7083.2.4.80/2883.2.4.81 to 83.2.4.9483.2.4.9514
7183.2.4.96/2883.2.4.97 to 83.2.4.11083.2.4.11114
7283.2.4.112/2883.2.4.113 to 83.2.4.12683.2.4.12714
7383.2.4.128/2883.2.4.129 to 83.2.4.14283.2.4.14314
7483.2.4.144/2883.2.4.145 to 83.2.4.15883.2.4.15914
7583.2.4.160/2883.2.4.161 to 83.2.4.17483.2.4.17514
7683.2.4.176/2883.2.4.177 to 83.2.4.19083.2.4.19114
7783.2.4.192/2883.2.4.193 to 83.2.4.20683.2.4.20714
7883.2.4.208/2883.2.4.209 to 83.2.4.22283.2.4.22314
7983.2.4.224/2883.2.4.225 to 83.2.4.23883.2.4.23914
8083.2.4.240/2883.2.4.241 to 83.2.4.25483.2.4.25514
8183.2.5.0/2883.2.5.1 to 83.2.5.1483.2.5.1514
8283.2.5.16/2883.2.5.17 to 83.2.5.3083.2.5.3114
8383.2.5.32/2883.2.5.33 to 83.2.5.4683.2.5.4714
8483.2.5.48/2883.2.5.49 to 83.2.5.6283.2.5.6314
8583.2.5.64/2883.2.5.65 to 83.2.5.7883.2.5.7914
8683.2.5.80/2883.2.5.81 to 83.2.5.9483.2.5.9514
8783.2.5.96/2883.2.5.97 to 83.2.5.11083.2.5.11114
8883.2.5.112/2883.2.5.113 to 83.2.5.12683.2.5.12714
8983.2.5.128/2883.2.5.129 to 83.2.5.14283.2.5.14314
9083.2.5.144/2883.2.5.145 to 83.2.5.15883.2.5.15914
9183.2.5.160/2883.2.5.161 to 83.2.5.17483.2.5.17514
9283.2.5.176/2883.2.5.177 to 83.2.5.19083.2.5.19114
9383.2.5.192/2883.2.5.193 to 83.2.5.20683.2.5.20714
9483.2.5.208/2883.2.5.209 to 83.2.5.22283.2.5.22314
9583.2.5.224/2883.2.5.225 to 83.2.5.23883.2.5.23914
9683.2.5.240/2883.2.5.241 to 83.2.5.25483.2.5.25514
9783.2.6.0/2883.2.6.1 to 83.2.6.1483.2.6.1514
9883.2.6.16/2883.2.6.17 to 83.2.6.3083.2.6.3114
9983.2.6.32/2883.2.6.33 to 83.2.6.4683.2.6.4714
10083.2.6.48/2883.2.6.49 to 83.2.6.6283.2.6.6314
10183.2.6.64/2883.2.6.65 to 83.2.6.7883.2.6.7914
10283.2.6.80/2883.2.6.81 to 83.2.6.9483.2.6.9514
10383.2.6.96/2883.2.6.97 to 83.2.6.11083.2.6.11114
10483.2.6.112/2883.2.6.113 to 83.2.6.12683.2.6.12714
10583.2.6.128/2883.2.6.129 to 83.2.6.14283.2.6.14314
10683.2.6.144/2883.2.6.145 to 83.2.6.15883.2.6.15914
10783.2.6.160/2883.2.6.161 to 83.2.6.17483.2.6.17514
10883.2.6.176/2883.2.6.177 to 83.2.6.19083.2.6.19114
10983.2.6.192/2883.2.6.193 to 83.2.6.20683.2.6.20714
11083.2.6.208/2883.2.6.209 to 83.2.6.22283.2.6.22314
11183.2.6.224/2883.2.6.225 to 83.2.6.23883.2.6.23914
11283.2.6.240/2883.2.6.241 to 83.2.6.25483.2.6.25514
11383.2.7.0/2883.2.7.1 to 83.2.7.1483.2.7.1514
11483.2.7.16/2883.2.7.17 to 83.2.7.3083.2.7.3114
11583.2.7.32/2883.2.7.33 to 83.2.7.4683.2.7.4714
11683.2.7.48/2883.2.7.49 to 83.2.7.6283.2.7.6314
11783.2.7.64/2883.2.7.65 to 83.2.7.7883.2.7.7914
11883.2.7.80/2883.2.7.81 to 83.2.7.9483.2.7.9514
11983.2.7.96/2883.2.7.97 to 83.2.7.11083.2.7.11114
12083.2.7.112/2883.2.7.113 to 83.2.7.12683.2.7.12714
12183.2.7.128/2883.2.7.129 to 83.2.7.14283.2.7.14314
12283.2.7.144/2883.2.7.145 to 83.2.7.15883.2.7.15914
12383.2.7.160/2883.2.7.161 to 83.2.7.17483.2.7.17514
12483.2.7.176/2883.2.7.177 to 83.2.7.19083.2.7.19114
12583.2.7.192/2883.2.7.193 to 83.2.7.20683.2.7.20714
12683.2.7.208/2883.2.7.209 to 83.2.7.22283.2.7.22314
12783.2.7.224/2883.2.7.225 to 83.2.7.23883.2.7.23914
12883.2.7.240/2883.2.7.241 to 83.2.7.25483.2.7.25514
12983.2.8.0/2883.2.8.1 to 83.2.8.1483.2.8.1514
13083.2.8.16/2883.2.8.17 to 83.2.8.3083.2.8.3114
13183.2.8.32/2883.2.8.33 to 83.2.8.4683.2.8.4714
13283.2.8.48/2883.2.8.49 to 83.2.8.6283.2.8.6314
13383.2.8.64/2883.2.8.65 to 83.2.8.7883.2.8.7914
13483.2.8.80/2883.2.8.81 to 83.2.8.9483.2.8.9514
13583.2.8.96/2883.2.8.97 to 83.2.8.11083.2.8.11114
13683.2.8.112/2883.2.8.113 to 83.2.8.12683.2.8.12714
13783.2.8.128/2883.2.8.129 to 83.2.8.14283.2.8.14314
13883.2.8.144/2883.2.8.145 to 83.2.8.15883.2.8.15914
13983.2.8.160/2883.2.8.161 to 83.2.8.17483.2.8.17514
14083.2.8.176/2883.2.8.177 to 83.2.8.19083.2.8.19114
14183.2.8.192/2883.2.8.193 to 83.2.8.20683.2.8.20714
14283.2.8.208/2883.2.8.209 to 83.2.8.22283.2.8.22314
14383.2.8.224/2883.2.8.225 to 83.2.8.23883.2.8.23914
14483.2.8.240/2883.2.8.241 to 83.2.8.25483.2.8.25514
14583.2.9.0/2883.2.9.1 to 83.2.9.1483.2.9.1514
14683.2.9.16/2883.2.9.17 to 83.2.9.3083.2.9.3114
14783.2.9.32/2883.2.9.33 to 83.2.9.4683.2.9.4714
14883.2.9.48/2883.2.9.49 to 83.2.9.6283.2.9.6314
14983.2.9.64/2883.2.9.65 to 83.2.9.7883.2.9.7914
15083.2.9.80/2883.2.9.81 to 83.2.9.9483.2.9.9514
15183.2.9.96/2883.2.9.97 to 83.2.9.11083.2.9.11114
15283.2.9.112/2883.2.9.113 to 83.2.9.12683.2.9.12714
15383.2.9.128/2883.2.9.129 to 83.2.9.14283.2.9.14314
15483.2.9.144/2883.2.9.145 to 83.2.9.15883.2.9.15914
15583.2.9.160/2883.2.9.161 to 83.2.9.17483.2.9.17514
15683.2.9.176/2883.2.9.177 to 83.2.9.19083.2.9.19114
15783.2.9.192/2883.2.9.193 to 83.2.9.20683.2.9.20714
15883.2.9.208/2883.2.9.209 to 83.2.9.22283.2.9.22314
15983.2.9.224/2883.2.9.225 to 83.2.9.23883.2.9.23914
16083.2.9.240/2883.2.9.241 to 83.2.9.25483.2.9.25514
16183.2.10.0/2883.2.10.1 to 83.2.10.1483.2.10.1514
16283.2.10.16/2883.2.10.17 to 83.2.10.3083.2.10.3114
16383.2.10.32/2883.2.10.33 to 83.2.10.4683.2.10.4714
16483.2.10.48/2883.2.10.49 to 83.2.10.6283.2.10.6314
16583.2.10.64/2883.2.10.65 to 83.2.10.7883.2.10.7914
16683.2.10.80/2883.2.10.81 to 83.2.10.9483.2.10.9514
16783.2.10.96/2883.2.10.97 to 83.2.10.11083.2.10.11114
16883.2.10.112/2883.2.10.113 to 83.2.10.12683.2.10.12714
16983.2.10.128/2883.2.10.129 to 83.2.10.14283.2.10.14314
17083.2.10.144/2883.2.10.145 to 83.2.10.15883.2.10.15914
17183.2.10.160/2883.2.10.161 to 83.2.10.17483.2.10.17514
17283.2.10.176/2883.2.10.177 to 83.2.10.19083.2.10.19114
17383.2.10.192/2883.2.10.193 to 83.2.10.20683.2.10.20714
17483.2.10.208/2883.2.10.209 to 83.2.10.22283.2.10.22314
17583.2.10.224/2883.2.10.225 to 83.2.10.23883.2.10.23914
17683.2.10.240/2883.2.10.241 to 83.2.10.25483.2.10.25514
17783.2.11.0/2883.2.11.1 to 83.2.11.1483.2.11.1514
17883.2.11.16/2883.2.11.17 to 83.2.11.3083.2.11.3114
17983.2.11.32/2883.2.11.33 to 83.2.11.4683.2.11.4714
18083.2.11.48/2883.2.11.49 to 83.2.11.6283.2.11.6314
18183.2.11.64/2883.2.11.65 to 83.2.11.7883.2.11.7914
18283.2.11.80/2883.2.11.81 to 83.2.11.9483.2.11.9514
18383.2.11.96/2883.2.11.97 to 83.2.11.11083.2.11.11114
18483.2.11.112/2883.2.11.113 to 83.2.11.12683.2.11.12714
18583.2.11.128/2883.2.11.129 to 83.2.11.14283.2.11.14314
18683.2.11.144/2883.2.11.145 to 83.2.11.15883.2.11.15914
18783.2.11.160/2883.2.11.161 to 83.2.11.17483.2.11.17514
18883.2.11.176/2883.2.11.177 to 83.2.11.19083.2.11.19114
18983.2.11.192/2883.2.11.193 to 83.2.11.20683.2.11.20714
19083.2.11.208/2883.2.11.209 to 83.2.11.22283.2.11.22314
19183.2.11.224/2883.2.11.225 to 83.2.11.23883.2.11.23914
19283.2.11.240/2883.2.11.241 to 83.2.11.25483.2.11.25514
19383.2.12.0/2883.2.12.1 to 83.2.12.1483.2.12.1514
19483.2.12.16/2883.2.12.17 to 83.2.12.3083.2.12.3114
19583.2.12.32/2883.2.12.33 to 83.2.12.4683.2.12.4714
19683.2.12.48/2883.2.12.49 to 83.2.12.6283.2.12.6314
19783.2.12.64/2883.2.12.65 to 83.2.12.7883.2.12.7914
19883.2.12.80/2883.2.12.81 to 83.2.12.9483.2.12.9514
19983.2.12.96/2883.2.12.97 to 83.2.12.11083.2.12.11114
20083.2.12.112/2883.2.12.113 to 83.2.12.12683.2.12.12714
20183.2.12.128/2883.2.12.129 to 83.2.12.14283.2.12.14314
20283.2.12.144/2883.2.12.145 to 83.2.12.15883.2.12.15914
20383.2.12.160/2883.2.12.161 to 83.2.12.17483.2.12.17514
20483.2.12.176/2883.2.12.177 to 83.2.12.19083.2.12.19114
20583.2.12.192/2883.2.12.193 to 83.2.12.20683.2.12.20714
20683.2.12.208/2883.2.12.209 to 83.2.12.22283.2.12.22314
20783.2.12.224/2883.2.12.225 to 83.2.12.23883.2.12.23914
20883.2.12.240/2883.2.12.241 to 83.2.12.25483.2.12.25514
20983.2.13.0/2883.2.13.1 to 83.2.13.1483.2.13.1514
21083.2.13.16/2883.2.13.17 to 83.2.13.3083.2.13.3114
21183.2.13.32/2883.2.13.33 to 83.2.13.4683.2.13.4714
21283.2.13.48/2883.2.13.49 to 83.2.13.6283.2.13.6314
21383.2.13.64/2883.2.13.65 to 83.2.13.7883.2.13.7914
21483.2.13.80/2883.2.13.81 to 83.2.13.9483.2.13.9514
21583.2.13.96/2883.2.13.97 to 83.2.13.11083.2.13.11114
21683.2.13.112/2883.2.13.113 to 83.2.13.12683.2.13.12714
21783.2.13.128/2883.2.13.129 to 83.2.13.14283.2.13.14314
21883.2.13.144/2883.2.13.145 to 83.2.13.15883.2.13.15914
21983.2.13.160/2883.2.13.161 to 83.2.13.17483.2.13.17514
22083.2.13.176/2883.2.13.177 to 83.2.13.19083.2.13.19114
22183.2.13.192/2883.2.13.193 to 83.2.13.20683.2.13.20714
22283.2.13.208/2883.2.13.209 to 83.2.13.22283.2.13.22314
22383.2.13.224/2883.2.13.225 to 83.2.13.23883.2.13.23914
22483.2.13.240/2883.2.13.241 to 83.2.13.25483.2.13.25514
22583.2.14.0/2883.2.14.1 to 83.2.14.1483.2.14.1514
22683.2.14.16/2883.2.14.17 to 83.2.14.3083.2.14.3114
22783.2.14.32/2883.2.14.33 to 83.2.14.4683.2.14.4714
22883.2.14.48/2883.2.14.49 to 83.2.14.6283.2.14.6314
22983.2.14.64/2883.2.14.65 to 83.2.14.7883.2.14.7914
23083.2.14.80/2883.2.14.81 to 83.2.14.9483.2.14.9514
23183.2.14.96/2883.2.14.97 to 83.2.14.11083.2.14.11114
23283.2.14.112/2883.2.14.113 to 83.2.14.12683.2.14.12714
23383.2.14.128/2883.2.14.129 to 83.2.14.14283.2.14.14314
23483.2.14.144/2883.2.14.145 to 83.2.14.15883.2.14.15914
23583.2.14.160/2883.2.14.161 to 83.2.14.17483.2.14.17514
23683.2.14.176/2883.2.14.177 to 83.2.14.19083.2.14.19114
23783.2.14.192/2883.2.14.193 to 83.2.14.20683.2.14.20714
23883.2.14.208/2883.2.14.209 to 83.2.14.22283.2.14.22314
23983.2.14.224/2883.2.14.225 to 83.2.14.23883.2.14.23914
24083.2.14.240/2883.2.14.241 to 83.2.14.25483.2.14.25514
24183.2.15.0/2883.2.15.1 to 83.2.15.1483.2.15.1514
24283.2.15.16/2883.2.15.17 to 83.2.15.3083.2.15.3114
24383.2.15.32/2883.2.15.33 to 83.2.15.4683.2.15.4714
24483.2.15.48/2883.2.15.49 to 83.2.15.6283.2.15.6314
24583.2.15.64/2883.2.15.65 to 83.2.15.7883.2.15.7914
24683.2.15.80/2883.2.15.81 to 83.2.15.9483.2.15.9514
24783.2.15.96/2883.2.15.97 to 83.2.15.11083.2.15.11114
24883.2.15.112/2883.2.15.113 to 83.2.15.12683.2.15.12714
24983.2.15.128/2883.2.15.129 to 83.2.15.14283.2.15.14314
25083.2.15.144/2883.2.15.145 to 83.2.15.15883.2.15.15914
25183.2.15.160/2883.2.15.161 to 83.2.15.17483.2.15.17514
25283.2.15.176/2883.2.15.177 to 83.2.15.19083.2.15.19114
25383.2.15.192/2883.2.15.193 to 83.2.15.20683.2.15.20714
25483.2.15.208/2883.2.15.209 to 83.2.15.22283.2.15.22314
25583.2.15.224/2883.2.15.225 to 83.2.15.23883.2.15.23914
25683.2.15.240/2883.2.15.241 to 83.2.15.25483.2.15.25514

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