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.

Network55.69.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
55.69.0.0
Broadcast address
55.69.255.255
First usable
55.69.0.1
Last usable
55.69.255.254
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 37450000 · Integer 927268864 to 927334399
Reverse DNS zone
69.55.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110111.01000101..00000000.0000000055.69.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network00110111.01000101..00000000.0000000055.69.0.0
Broadcast00110111.01000101..11111111.1111111155.69.255.255
Split into smaller subnets/25

55.69.0.0/16 makes 512 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
155.69.0.0/2555.69.0.1 to 55.69.0.12655.69.0.127126
255.69.0.128/2555.69.0.129 to 55.69.0.25455.69.0.255126
355.69.1.0/2555.69.1.1 to 55.69.1.12655.69.1.127126
455.69.1.128/2555.69.1.129 to 55.69.1.25455.69.1.255126
555.69.2.0/2555.69.2.1 to 55.69.2.12655.69.2.127126
655.69.2.128/2555.69.2.129 to 55.69.2.25455.69.2.255126
755.69.3.0/2555.69.3.1 to 55.69.3.12655.69.3.127126
855.69.3.128/2555.69.3.129 to 55.69.3.25455.69.3.255126
955.69.4.0/2555.69.4.1 to 55.69.4.12655.69.4.127126
1055.69.4.128/2555.69.4.129 to 55.69.4.25455.69.4.255126
1155.69.5.0/2555.69.5.1 to 55.69.5.12655.69.5.127126
1255.69.5.128/2555.69.5.129 to 55.69.5.25455.69.5.255126
1355.69.6.0/2555.69.6.1 to 55.69.6.12655.69.6.127126
1455.69.6.128/2555.69.6.129 to 55.69.6.25455.69.6.255126
1555.69.7.0/2555.69.7.1 to 55.69.7.12655.69.7.127126
1655.69.7.128/2555.69.7.129 to 55.69.7.25455.69.7.255126
1755.69.8.0/2555.69.8.1 to 55.69.8.12655.69.8.127126
1855.69.8.128/2555.69.8.129 to 55.69.8.25455.69.8.255126
1955.69.9.0/2555.69.9.1 to 55.69.9.12655.69.9.127126
2055.69.9.128/2555.69.9.129 to 55.69.9.25455.69.9.255126
2155.69.10.0/2555.69.10.1 to 55.69.10.12655.69.10.127126
2255.69.10.128/2555.69.10.129 to 55.69.10.25455.69.10.255126
2355.69.11.0/2555.69.11.1 to 55.69.11.12655.69.11.127126
2455.69.11.128/2555.69.11.129 to 55.69.11.25455.69.11.255126
2555.69.12.0/2555.69.12.1 to 55.69.12.12655.69.12.127126
2655.69.12.128/2555.69.12.129 to 55.69.12.25455.69.12.255126
2755.69.13.0/2555.69.13.1 to 55.69.13.12655.69.13.127126
2855.69.13.128/2555.69.13.129 to 55.69.13.25455.69.13.255126
2955.69.14.0/2555.69.14.1 to 55.69.14.12655.69.14.127126
3055.69.14.128/2555.69.14.129 to 55.69.14.25455.69.14.255126
3155.69.15.0/2555.69.15.1 to 55.69.15.12655.69.15.127126
3255.69.15.128/2555.69.15.129 to 55.69.15.25455.69.15.255126
3355.69.16.0/2555.69.16.1 to 55.69.16.12655.69.16.127126
3455.69.16.128/2555.69.16.129 to 55.69.16.25455.69.16.255126
3555.69.17.0/2555.69.17.1 to 55.69.17.12655.69.17.127126
3655.69.17.128/2555.69.17.129 to 55.69.17.25455.69.17.255126
3755.69.18.0/2555.69.18.1 to 55.69.18.12655.69.18.127126
3855.69.18.128/2555.69.18.129 to 55.69.18.25455.69.18.255126
3955.69.19.0/2555.69.19.1 to 55.69.19.12655.69.19.127126
4055.69.19.128/2555.69.19.129 to 55.69.19.25455.69.19.255126
4155.69.20.0/2555.69.20.1 to 55.69.20.12655.69.20.127126
4255.69.20.128/2555.69.20.129 to 55.69.20.25455.69.20.255126
4355.69.21.0/2555.69.21.1 to 55.69.21.12655.69.21.127126
4455.69.21.128/2555.69.21.129 to 55.69.21.25455.69.21.255126
4555.69.22.0/2555.69.22.1 to 55.69.22.12655.69.22.127126
4655.69.22.128/2555.69.22.129 to 55.69.22.25455.69.22.255126
4755.69.23.0/2555.69.23.1 to 55.69.23.12655.69.23.127126
4855.69.23.128/2555.69.23.129 to 55.69.23.25455.69.23.255126
4955.69.24.0/2555.69.24.1 to 55.69.24.12655.69.24.127126
5055.69.24.128/2555.69.24.129 to 55.69.24.25455.69.24.255126
5155.69.25.0/2555.69.25.1 to 55.69.25.12655.69.25.127126
5255.69.25.128/2555.69.25.129 to 55.69.25.25455.69.25.255126
5355.69.26.0/2555.69.26.1 to 55.69.26.12655.69.26.127126
5455.69.26.128/2555.69.26.129 to 55.69.26.25455.69.26.255126
5555.69.27.0/2555.69.27.1 to 55.69.27.12655.69.27.127126
5655.69.27.128/2555.69.27.129 to 55.69.27.25455.69.27.255126
5755.69.28.0/2555.69.28.1 to 55.69.28.12655.69.28.127126
5855.69.28.128/2555.69.28.129 to 55.69.28.25455.69.28.255126
5955.69.29.0/2555.69.29.1 to 55.69.29.12655.69.29.127126
6055.69.29.128/2555.69.29.129 to 55.69.29.25455.69.29.255126
6155.69.30.0/2555.69.30.1 to 55.69.30.12655.69.30.127126
6255.69.30.128/2555.69.30.129 to 55.69.30.25455.69.30.255126
6355.69.31.0/2555.69.31.1 to 55.69.31.12655.69.31.127126
6455.69.31.128/2555.69.31.129 to 55.69.31.25455.69.31.255126
6555.69.32.0/2555.69.32.1 to 55.69.32.12655.69.32.127126
6655.69.32.128/2555.69.32.129 to 55.69.32.25455.69.32.255126
6755.69.33.0/2555.69.33.1 to 55.69.33.12655.69.33.127126
6855.69.33.128/2555.69.33.129 to 55.69.33.25455.69.33.255126
6955.69.34.0/2555.69.34.1 to 55.69.34.12655.69.34.127126
7055.69.34.128/2555.69.34.129 to 55.69.34.25455.69.34.255126
7155.69.35.0/2555.69.35.1 to 55.69.35.12655.69.35.127126
7255.69.35.128/2555.69.35.129 to 55.69.35.25455.69.35.255126
7355.69.36.0/2555.69.36.1 to 55.69.36.12655.69.36.127126
7455.69.36.128/2555.69.36.129 to 55.69.36.25455.69.36.255126
7555.69.37.0/2555.69.37.1 to 55.69.37.12655.69.37.127126
7655.69.37.128/2555.69.37.129 to 55.69.37.25455.69.37.255126
7755.69.38.0/2555.69.38.1 to 55.69.38.12655.69.38.127126
7855.69.38.128/2555.69.38.129 to 55.69.38.25455.69.38.255126
7955.69.39.0/2555.69.39.1 to 55.69.39.12655.69.39.127126
8055.69.39.128/2555.69.39.129 to 55.69.39.25455.69.39.255126
8155.69.40.0/2555.69.40.1 to 55.69.40.12655.69.40.127126
8255.69.40.128/2555.69.40.129 to 55.69.40.25455.69.40.255126
8355.69.41.0/2555.69.41.1 to 55.69.41.12655.69.41.127126
8455.69.41.128/2555.69.41.129 to 55.69.41.25455.69.41.255126
8555.69.42.0/2555.69.42.1 to 55.69.42.12655.69.42.127126
8655.69.42.128/2555.69.42.129 to 55.69.42.25455.69.42.255126
8755.69.43.0/2555.69.43.1 to 55.69.43.12655.69.43.127126
8855.69.43.128/2555.69.43.129 to 55.69.43.25455.69.43.255126
8955.69.44.0/2555.69.44.1 to 55.69.44.12655.69.44.127126
9055.69.44.128/2555.69.44.129 to 55.69.44.25455.69.44.255126
9155.69.45.0/2555.69.45.1 to 55.69.45.12655.69.45.127126
9255.69.45.128/2555.69.45.129 to 55.69.45.25455.69.45.255126
9355.69.46.0/2555.69.46.1 to 55.69.46.12655.69.46.127126
9455.69.46.128/2555.69.46.129 to 55.69.46.25455.69.46.255126
9555.69.47.0/2555.69.47.1 to 55.69.47.12655.69.47.127126
9655.69.47.128/2555.69.47.129 to 55.69.47.25455.69.47.255126
9755.69.48.0/2555.69.48.1 to 55.69.48.12655.69.48.127126
9855.69.48.128/2555.69.48.129 to 55.69.48.25455.69.48.255126
9955.69.49.0/2555.69.49.1 to 55.69.49.12655.69.49.127126
10055.69.49.128/2555.69.49.129 to 55.69.49.25455.69.49.255126
10155.69.50.0/2555.69.50.1 to 55.69.50.12655.69.50.127126
10255.69.50.128/2555.69.50.129 to 55.69.50.25455.69.50.255126
10355.69.51.0/2555.69.51.1 to 55.69.51.12655.69.51.127126
10455.69.51.128/2555.69.51.129 to 55.69.51.25455.69.51.255126
10555.69.52.0/2555.69.52.1 to 55.69.52.12655.69.52.127126
10655.69.52.128/2555.69.52.129 to 55.69.52.25455.69.52.255126
10755.69.53.0/2555.69.53.1 to 55.69.53.12655.69.53.127126
10855.69.53.128/2555.69.53.129 to 55.69.53.25455.69.53.255126
10955.69.54.0/2555.69.54.1 to 55.69.54.12655.69.54.127126
11055.69.54.128/2555.69.54.129 to 55.69.54.25455.69.54.255126
11155.69.55.0/2555.69.55.1 to 55.69.55.12655.69.55.127126
11255.69.55.128/2555.69.55.129 to 55.69.55.25455.69.55.255126
11355.69.56.0/2555.69.56.1 to 55.69.56.12655.69.56.127126
11455.69.56.128/2555.69.56.129 to 55.69.56.25455.69.56.255126
11555.69.57.0/2555.69.57.1 to 55.69.57.12655.69.57.127126
11655.69.57.128/2555.69.57.129 to 55.69.57.25455.69.57.255126
11755.69.58.0/2555.69.58.1 to 55.69.58.12655.69.58.127126
11855.69.58.128/2555.69.58.129 to 55.69.58.25455.69.58.255126
11955.69.59.0/2555.69.59.1 to 55.69.59.12655.69.59.127126
12055.69.59.128/2555.69.59.129 to 55.69.59.25455.69.59.255126
12155.69.60.0/2555.69.60.1 to 55.69.60.12655.69.60.127126
12255.69.60.128/2555.69.60.129 to 55.69.60.25455.69.60.255126
12355.69.61.0/2555.69.61.1 to 55.69.61.12655.69.61.127126
12455.69.61.128/2555.69.61.129 to 55.69.61.25455.69.61.255126
12555.69.62.0/2555.69.62.1 to 55.69.62.12655.69.62.127126
12655.69.62.128/2555.69.62.129 to 55.69.62.25455.69.62.255126
12755.69.63.0/2555.69.63.1 to 55.69.63.12655.69.63.127126
12855.69.63.128/2555.69.63.129 to 55.69.63.25455.69.63.255126
12955.69.64.0/2555.69.64.1 to 55.69.64.12655.69.64.127126
13055.69.64.128/2555.69.64.129 to 55.69.64.25455.69.64.255126
13155.69.65.0/2555.69.65.1 to 55.69.65.12655.69.65.127126
13255.69.65.128/2555.69.65.129 to 55.69.65.25455.69.65.255126
13355.69.66.0/2555.69.66.1 to 55.69.66.12655.69.66.127126
13455.69.66.128/2555.69.66.129 to 55.69.66.25455.69.66.255126
13555.69.67.0/2555.69.67.1 to 55.69.67.12655.69.67.127126
13655.69.67.128/2555.69.67.129 to 55.69.67.25455.69.67.255126
13755.69.68.0/2555.69.68.1 to 55.69.68.12655.69.68.127126
13855.69.68.128/2555.69.68.129 to 55.69.68.25455.69.68.255126
13955.69.69.0/2555.69.69.1 to 55.69.69.12655.69.69.127126
14055.69.69.128/2555.69.69.129 to 55.69.69.25455.69.69.255126
14155.69.70.0/2555.69.70.1 to 55.69.70.12655.69.70.127126
14255.69.70.128/2555.69.70.129 to 55.69.70.25455.69.70.255126
14355.69.71.0/2555.69.71.1 to 55.69.71.12655.69.71.127126
14455.69.71.128/2555.69.71.129 to 55.69.71.25455.69.71.255126
14555.69.72.0/2555.69.72.1 to 55.69.72.12655.69.72.127126
14655.69.72.128/2555.69.72.129 to 55.69.72.25455.69.72.255126
14755.69.73.0/2555.69.73.1 to 55.69.73.12655.69.73.127126
14855.69.73.128/2555.69.73.129 to 55.69.73.25455.69.73.255126
14955.69.74.0/2555.69.74.1 to 55.69.74.12655.69.74.127126
15055.69.74.128/2555.69.74.129 to 55.69.74.25455.69.74.255126
15155.69.75.0/2555.69.75.1 to 55.69.75.12655.69.75.127126
15255.69.75.128/2555.69.75.129 to 55.69.75.25455.69.75.255126
15355.69.76.0/2555.69.76.1 to 55.69.76.12655.69.76.127126
15455.69.76.128/2555.69.76.129 to 55.69.76.25455.69.76.255126
15555.69.77.0/2555.69.77.1 to 55.69.77.12655.69.77.127126
15655.69.77.128/2555.69.77.129 to 55.69.77.25455.69.77.255126
15755.69.78.0/2555.69.78.1 to 55.69.78.12655.69.78.127126
15855.69.78.128/2555.69.78.129 to 55.69.78.25455.69.78.255126
15955.69.79.0/2555.69.79.1 to 55.69.79.12655.69.79.127126
16055.69.79.128/2555.69.79.129 to 55.69.79.25455.69.79.255126
16155.69.80.0/2555.69.80.1 to 55.69.80.12655.69.80.127126
16255.69.80.128/2555.69.80.129 to 55.69.80.25455.69.80.255126
16355.69.81.0/2555.69.81.1 to 55.69.81.12655.69.81.127126
16455.69.81.128/2555.69.81.129 to 55.69.81.25455.69.81.255126
16555.69.82.0/2555.69.82.1 to 55.69.82.12655.69.82.127126
16655.69.82.128/2555.69.82.129 to 55.69.82.25455.69.82.255126
16755.69.83.0/2555.69.83.1 to 55.69.83.12655.69.83.127126
16855.69.83.128/2555.69.83.129 to 55.69.83.25455.69.83.255126
16955.69.84.0/2555.69.84.1 to 55.69.84.12655.69.84.127126
17055.69.84.128/2555.69.84.129 to 55.69.84.25455.69.84.255126
17155.69.85.0/2555.69.85.1 to 55.69.85.12655.69.85.127126
17255.69.85.128/2555.69.85.129 to 55.69.85.25455.69.85.255126
17355.69.86.0/2555.69.86.1 to 55.69.86.12655.69.86.127126
17455.69.86.128/2555.69.86.129 to 55.69.86.25455.69.86.255126
17555.69.87.0/2555.69.87.1 to 55.69.87.12655.69.87.127126
17655.69.87.128/2555.69.87.129 to 55.69.87.25455.69.87.255126
17755.69.88.0/2555.69.88.1 to 55.69.88.12655.69.88.127126
17855.69.88.128/2555.69.88.129 to 55.69.88.25455.69.88.255126
17955.69.89.0/2555.69.89.1 to 55.69.89.12655.69.89.127126
18055.69.89.128/2555.69.89.129 to 55.69.89.25455.69.89.255126
18155.69.90.0/2555.69.90.1 to 55.69.90.12655.69.90.127126
18255.69.90.128/2555.69.90.129 to 55.69.90.25455.69.90.255126
18355.69.91.0/2555.69.91.1 to 55.69.91.12655.69.91.127126
18455.69.91.128/2555.69.91.129 to 55.69.91.25455.69.91.255126
18555.69.92.0/2555.69.92.1 to 55.69.92.12655.69.92.127126
18655.69.92.128/2555.69.92.129 to 55.69.92.25455.69.92.255126
18755.69.93.0/2555.69.93.1 to 55.69.93.12655.69.93.127126
18855.69.93.128/2555.69.93.129 to 55.69.93.25455.69.93.255126
18955.69.94.0/2555.69.94.1 to 55.69.94.12655.69.94.127126
19055.69.94.128/2555.69.94.129 to 55.69.94.25455.69.94.255126
19155.69.95.0/2555.69.95.1 to 55.69.95.12655.69.95.127126
19255.69.95.128/2555.69.95.129 to 55.69.95.25455.69.95.255126
19355.69.96.0/2555.69.96.1 to 55.69.96.12655.69.96.127126
19455.69.96.128/2555.69.96.129 to 55.69.96.25455.69.96.255126
19555.69.97.0/2555.69.97.1 to 55.69.97.12655.69.97.127126
19655.69.97.128/2555.69.97.129 to 55.69.97.25455.69.97.255126
19755.69.98.0/2555.69.98.1 to 55.69.98.12655.69.98.127126
19855.69.98.128/2555.69.98.129 to 55.69.98.25455.69.98.255126
19955.69.99.0/2555.69.99.1 to 55.69.99.12655.69.99.127126
20055.69.99.128/2555.69.99.129 to 55.69.99.25455.69.99.255126
20155.69.100.0/2555.69.100.1 to 55.69.100.12655.69.100.127126
20255.69.100.128/2555.69.100.129 to 55.69.100.25455.69.100.255126
20355.69.101.0/2555.69.101.1 to 55.69.101.12655.69.101.127126
20455.69.101.128/2555.69.101.129 to 55.69.101.25455.69.101.255126
20555.69.102.0/2555.69.102.1 to 55.69.102.12655.69.102.127126
20655.69.102.128/2555.69.102.129 to 55.69.102.25455.69.102.255126
20755.69.103.0/2555.69.103.1 to 55.69.103.12655.69.103.127126
20855.69.103.128/2555.69.103.129 to 55.69.103.25455.69.103.255126
20955.69.104.0/2555.69.104.1 to 55.69.104.12655.69.104.127126
21055.69.104.128/2555.69.104.129 to 55.69.104.25455.69.104.255126
21155.69.105.0/2555.69.105.1 to 55.69.105.12655.69.105.127126
21255.69.105.128/2555.69.105.129 to 55.69.105.25455.69.105.255126
21355.69.106.0/2555.69.106.1 to 55.69.106.12655.69.106.127126
21455.69.106.128/2555.69.106.129 to 55.69.106.25455.69.106.255126
21555.69.107.0/2555.69.107.1 to 55.69.107.12655.69.107.127126
21655.69.107.128/2555.69.107.129 to 55.69.107.25455.69.107.255126
21755.69.108.0/2555.69.108.1 to 55.69.108.12655.69.108.127126
21855.69.108.128/2555.69.108.129 to 55.69.108.25455.69.108.255126
21955.69.109.0/2555.69.109.1 to 55.69.109.12655.69.109.127126
22055.69.109.128/2555.69.109.129 to 55.69.109.25455.69.109.255126
22155.69.110.0/2555.69.110.1 to 55.69.110.12655.69.110.127126
22255.69.110.128/2555.69.110.129 to 55.69.110.25455.69.110.255126
22355.69.111.0/2555.69.111.1 to 55.69.111.12655.69.111.127126
22455.69.111.128/2555.69.111.129 to 55.69.111.25455.69.111.255126
22555.69.112.0/2555.69.112.1 to 55.69.112.12655.69.112.127126
22655.69.112.128/2555.69.112.129 to 55.69.112.25455.69.112.255126
22755.69.113.0/2555.69.113.1 to 55.69.113.12655.69.113.127126
22855.69.113.128/2555.69.113.129 to 55.69.113.25455.69.113.255126
22955.69.114.0/2555.69.114.1 to 55.69.114.12655.69.114.127126
23055.69.114.128/2555.69.114.129 to 55.69.114.25455.69.114.255126
23155.69.115.0/2555.69.115.1 to 55.69.115.12655.69.115.127126
23255.69.115.128/2555.69.115.129 to 55.69.115.25455.69.115.255126
23355.69.116.0/2555.69.116.1 to 55.69.116.12655.69.116.127126
23455.69.116.128/2555.69.116.129 to 55.69.116.25455.69.116.255126
23555.69.117.0/2555.69.117.1 to 55.69.117.12655.69.117.127126
23655.69.117.128/2555.69.117.129 to 55.69.117.25455.69.117.255126
23755.69.118.0/2555.69.118.1 to 55.69.118.12655.69.118.127126
23855.69.118.128/2555.69.118.129 to 55.69.118.25455.69.118.255126
23955.69.119.0/2555.69.119.1 to 55.69.119.12655.69.119.127126
24055.69.119.128/2555.69.119.129 to 55.69.119.25455.69.119.255126
24155.69.120.0/2555.69.120.1 to 55.69.120.12655.69.120.127126
24255.69.120.128/2555.69.120.129 to 55.69.120.25455.69.120.255126
24355.69.121.0/2555.69.121.1 to 55.69.121.12655.69.121.127126
24455.69.121.128/2555.69.121.129 to 55.69.121.25455.69.121.255126
24555.69.122.0/2555.69.122.1 to 55.69.122.12655.69.122.127126
24655.69.122.128/2555.69.122.129 to 55.69.122.25455.69.122.255126
24755.69.123.0/2555.69.123.1 to 55.69.123.12655.69.123.127126
24855.69.123.128/2555.69.123.129 to 55.69.123.25455.69.123.255126
24955.69.124.0/2555.69.124.1 to 55.69.124.12655.69.124.127126
25055.69.124.128/2555.69.124.129 to 55.69.124.25455.69.124.255126
25155.69.125.0/2555.69.125.1 to 55.69.125.12655.69.125.127126
25255.69.125.128/2555.69.125.129 to 55.69.125.25455.69.125.255126
25355.69.126.0/2555.69.126.1 to 55.69.126.12655.69.126.127126
25455.69.126.128/2555.69.126.129 to 55.69.126.25455.69.126.255126
25555.69.127.0/2555.69.127.1 to 55.69.127.12655.69.127.127126
25655.69.127.128/2555.69.127.129 to 55.69.127.25455.69.127.255126

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