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172.21.8.237



Here you can find all lookup results for private IP address 172.21.8.237. If you are trying to find how to login to your wireless router, access point, extender or repeater, you can access the built-in management page by clicking one of the following links:

http://172.21.8.237 or https://172.21.8.237 (note: https is more secure and the use of www is not needed)

The most used default username and password to gain access to the router settings is 'admin' or 'setup' and in case of a TP Link, Netgear or D-Link wireless router, also known as a wifi router, you can also find the default settings on a sticker on the back of the device. If this doesn't work or you, then you could choose to reset the router. To do this, you need to press and hold it's reset button for approximately 10 seconds. This will restore the factory settings and enables you to log in with the details specified on the sticker, through the default login page. If it doesn't work through the wireless network, you could also try to stick a ethernet cable into the first port of the device.



IP address 172.21.8.237 is registered by the Internet Assigned Numbers Authority (IANA) as a part of private network 172.21.8.0/24.
IP addresses in the private space are not assigned to any specific organization, including your ISP (Internet Service Provider), and everyone is allowed to use these IP addresses without the consent of a regional Internet registry as described in RFC 1918, unlike public IP addresses.

However, IP packets addressed from a private range cannot be sent through the public Internet, and so if such a private network needs to connect to the Internet, it has to be done through a network address translator (also called NAT) gateway, or a proxy server (usually reachable on port 8080 or 8081 if it doesn't work directly).

An example of a NAT gateway would be a wired or wireless router you receive from a broadband provider. The default address of such a device in network range 172.21.8.0/24 would traditionally be 172.21.8.1 or 172.21.8.254 depending on your provider and brand. A gateway web interface should be available through the HTTP (Hypertext Transfer Protocol) and/or HTTPS (Hypertext Transfer Protocol Secure) protocols. To try this, you should enter 'http://ip address' or 'https://ip address' in the browser's address bar of your favorite web browser like Google Chrome or Mozilla Firefox and log in with the username and password provided by your provider.

You can use these types of (private network) IP addresses in your local network and assign it to your devices such as a personal computer, laptop, tablet and/or smartphone. It is also possible to configure a range within a DHCP (Dynamic Host Configuration Protocol) server to do the IP assigning automatically.


Technical details

IP address 172.21.8.237  
OptionsSee your own public address
Address type Private
Protocol versionIPv4
Network classClass B
Conversions 2887059693 (decimal / iplong)
ac1508ed (hex / base 16)
172218237 (numeric)
Reverse DNS 237.8.21.172.in-addr.arpa
CIDR block172.21.8.0/24
Network range172.21.8.0 - 172.21.8.255
Network ID 172.21.8
Broadcast address 172.21.8.255


Private vs. Public IP addresses

As you might have noticed, we are talking a lot about public and private IP-addresses, but what are they, and what is the difference between them?

You have searched for 172.21.8.237, which is a private IP address and most likely related to your own Wi-Fi network. It is a combination of four numbers, called octets, which are separated by dots and can be used to access your router admin page. And because your router acts as a bridge between your local network and the internet, it also has another IP called a public IP address. The public IP address is assigned by your ISP, and is pretty much outside of your control.

The public IP address is built up in the same manner, also consisting out of four numbers separated by dots, but cannot be the same as the ones used for a private address. It is used to connect your network to the outside world and to communicate to the internet. Whenever you visit a website or send out an e-mail, your router will receive it through your private network and send the information out though your public interface.

Another difference is that public IP addresses given out by providers are likely to change as every router in the world needs a unique public IP address, basically just like people and their home address, so ISPs tend to use dynamic IP addresses to make sure they don’t need more than necessary because of the finite amount of available addresses. They do this on a per-request basis. When you disconnect your router from the internet, the ip address is revoked and given to the next user that connects.

It is also common to have a static public IP address, which doesn’t change regularly like a dynamic one does. Nowadays, this is almost strictly prohibited to servers that serve websites and e-mail and are based in datacenters around the world and are often referred to as ‘the cloud’. This makes sense, as these servers need to be available 24/7.

The biggest downside of a public IP address is that it is outside-facing and can reveal details like a rough estimate of the users' location, as you can also see on this website. Using a VPN, like we offer in our ‘Hide my IP’ service, can give you some peace of mind if you don’t like the idea of being ‘out in the open’ when browsing the internet. Because it is another layer on top of your network, it hides your public IP address from the internet as it gives you a randomized address. It’s even possible to completely obscure your physical location.
These days you can buy routers which have this option built-in, but the most common way of doing this, is by installing an app on your computer or phone.