Class C Ip Checker

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About Class C Ip Checker

Enter more information about the Class C Ip Checker tool!

Every device that connects to other devices to the internet is assigned a unique IP address. For systems to locate each other on distributed networks, like the internet, each node on the network is assigned a unique address.

This address is commonly known as ‘IP address’ or ‘IP.’ The IP address is a 32-bit binary address which consists of two sub-addresses that identify the network and the host of the network. The IP address consists of four sets of numbers ranging from 0 to 255 separated by a (.) in decimal form. For example, is a valid IP address.


There are five classes of IP addresses which are:

  • Class A

    The first bit of a class An address is always set to 0. It only leaves seven bits for the network portion of the address. Class A addresses range from – It means there can only be 128 network numbers.

  • Class B

    The first bit of a class B address is always set to 1 and the second bit is set to 0. It means 16,384 networks can be assigned class B addresses. The numbers range from –

  • Class C

    Class C addresses have their first two bits set to 1, and the third bit is set to 0. It means 2,097,152 networks can be assigned this class of address. The numbers range from –

  • Class D

    Class D addresses have their first three bits set to 1, and the fourth bit is set to 0. Class D addresses are used for multicasting applications. The numbers range from – and are reserved for multicast groups.

  • Class E

    Class E addresses are reserved for experimentation and testing and have never been utilized in any standard form.


Class A and B are assigned to very large and medium-sized organizations. Class C is the most popular class of addresses assigned to small companies and are the most used IP addresses. Small and medium-sized internet service providers purchase a pool of class C IP addresses which they assign to their customers. Internet service providers provide dynamic (shared) IP addresses to their customers. The reason for this is that since they are shared, they are cheaper and more popular. Secondly, the users that are assigned IP addresses do not use them 24/7. So when a user signs of or there is no traffic to a website, their IP addresses are assigned to other users and websites.

The pros of C class dynamic IP addresses are that they are cheap and more feasible for websites and users who are not heavy users of the internet. If you have five people sharing a WiFi in your home, you will be assigned a dynamic address, and when you are not using the internet, your address will be assigned to another user who just signs in. When you use the internet again, you will be assigned a different IP address. This IP address will be assigned from the available pool of class C IP addresses that your internet service provider has purchased.

As dynamic class C IP addresses are shared across multiple nodes, there are dangers associated with them. If your website has a dynamic C class IP address, it can affect your website’s ranking on search engines and your SEO efforts could be wasted. If a website which is sharing the same IP address as yours gets blacklisted, your website might also get blacklisted. It happens when a search engine blacklists a website. It does not blacklist a website by just its domain name but by its IP address as well. Search engines when they visit a website do so by its IP address, as the IP address is the unique identifier of the domain. Internet service providers foresee this possibility, and if a website gets blacklisted, they reassign new IP addresses to the other websites that were sharing the same dynamic class C IP address.

Internet service providers install firewalls and other necessary applications and hardware to ensure that their hosting service provider systems remain ‘clean’ and unaffected by malicious attacks. As hackers and other malicious people are constantly engaged in trying to break-in to websites and damage them internet service providers are forced to take measures to protect their networks and hosting services


If you have just purchased a hosting service for your website, you will be inquisitive to know which other websites are sharing the same class C IP address. Because it’s most likely that your website has been assigned this class of IP address and that the address is shared with other websites.

You can use a bulk IP checker from ErosSoft.COM. Just go to ErosSoft.COM from your search browser and scroll to the ‘Class C IP Checker’ icon and click on it. Or you can copy/paste ErosSoft.COM/class-c-ip-checker/ in the address bar of your search browser.

In the display page, you must enter at least two and a maximum of twenty domain names. After entering the domain names click the ‘Check Now’ button. The utility will run the test and return the results.

In the results, it will display the host names that you had entered, and against each hostname, it will display their IP address, Class C, and the status.

The results will show you the hosts that are sharing the same class C IP address and if the status is ‘valid’ then everything is ok. This duplicate IP address checker is handy to know which other websites are sharing the same IP address.

You can use this nifty tool from ErosSoft.COM anytime to run a class C IP address check anytime.

Besides from this, you can run a bulk IP blacklist checker. You can run this check from some sites on the internet. This test will show if the websites are clean and the tools in use to protect them from viruses, spam, and malware.