NMAP VS NESSUS – A Detailed Comparison 2022


Hey folks, in this article we are going to do a detailed comparison of NMAP VS NESSUS. These are very powerful tools for penetration testers which helps them a lot in their penetration testing process. I’ve created this Comparison Guide of NMAP vs NESSUS because many beginners are confused about NMAP and Nessus.

NMAP vs NESSUS – A Detailed Comparison 2021

In simple words, NMAP is a Network Mapper which is used to detect hosts and open ports and NESSUS is a Vulnerability Scanner used for scanning vulnerability.

Both of these tools are used in network penetration testing, but they are different from each other. If we use NMAP and Nessus properly then only we will be able to take advantage of its true potential.

If we want to compare these two tools, then we will have to understand the way they work, only then we will be able to differentiate the NMAP VS NESSUS properly.

What is NMAP?

NMAP is also known as Network Mapper. It is a free and open-source command-line network scanning tools which are used to scan IP address and ports in the network. 

NMAP is used by penetration testers and network administrators to find which devices are running on their network, discovering open ports and services, and detect vulnerabilities. 

It was developed by Gordon Lyon in September 1997. The main purpose of this tool is to help in mapping an entire network easily and to find open ports and services.

NMAP uses a combination of probe requests to discover the IP of active hosts.  After the scanning is done using NMAP, we will have a list of live hosts with their open ports. 

NMAP also attempts to gather more information about the open ports like running services, versions, etc. 

How to use NMAP?

Although NMAP is a command-line tool its GUI version is also available named ZENMAP. Which can be easily downloaded from its official website. Click Here

If you are using Linux then you can install ZENMAP using this command: 

Command: sudo apt-get install zenmap

After installation type this to open ZENMAP:

Command: sudo zenmap

After scanning a host machine, it will give you a result something like this.


ZENMAP is a GUI version of NMAP so it is not as powerful as NMAP. But it is highly recommended to use NMAP instead of ZENMAP because it has lots of different features and also it is relatively fast from ZENMAP.

NMAP also has a scripting engine that allows us to create complex NSE scripts.

These NSE scripts are divided into several categories like discovery, brute, exploit, malware, etc. which can be used as per our need.

What is NESSUS?

Nessus is a vulnerability scanning tool which is developed by Tenable, Inc. It also scans for open ports like NMAP but in addition, it also detects the running services on those open ports and gives us information that if these ports have any kind of potential security vulnerabilities which help system administrators to identify and fix those vulnerabilities.

Nessus is a web-based application that is installed on our local server. It uses different kinds of plugins to identify the vulnerabilities on the targeted machine.

At the time of writing this comparison guide, Nessus has more than 159000 plugins are available which get updated in every 24 hours.

These plugins are very helpful in finding vulnerabilities in Windows, Mac, Linux, Databases & Webservers. System Administrators can set up policies, scans, and view reports after logging into the Nessus dashboard. 

These policies are used for scanning specific types of vulnerabilities. Like policy related to databases can be used to identify potential vulnerabilities in database servers. 

Other policies may only look for web application vulnerabilities when we run it on the targeted website. 

Nessus Policies

After setting up the policy and the target, we can start our scanning process or we can also schedule it for later. 

When NESSUS completes its scanning process, it gives us a comprehensive report which contains lots of detailed information about potential vulnerabilities of the machines we scanned. 

Nessus Scan Results

The best part of Nessus is that it also gives recommendations to fix all the identified vulnerabilities. 

Nessus includes “informational alerts” and features a detailed write-up for every vulnerability discovered letting you recognize the severity of the vulnerability with mitigation tips.

Nessus is a premium vulnerability scanner, which has three plans.


Nessus cost depends upon the user. If you are a student and want to learn about the Nessus vulnerability scanner then you can download and use Nessus Essentials for free.

If you are a penetration tester or a consultant then you’ll have to purchase Nessus professional edition.


If you want to get more information about Nessus or to download it you can visit here.


So, this was a complete comparison between NMAP vs NESSUS. Both of these tools are very powerful if used properly. 

If you want to network scanning it’s highly recommended to use NMAP and for vulnerability scanning, you can use NESSUS. 

I hope you find this article helpful, if you have any questions or suggestions feel free to ask in the comments. I’ll be very happy to help you. 

Also Read: How to use Gobuster for Scanning Website’s Subdomains & Directories?


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