Port Scanner

10 Questions and Answers about the Port Scanner

This guide will walk you through this powerful online port scanning tool with ten core questions.

1. What is this Port Scanner?

This Port Scanner is a free online network tool that helps users check the status of ports for a specified IP address (defaulting to your own), thereby identifying potential security risks.

2. What makes this tool special?

Unlike other basic tools, this tool offers two scanning modes:

Common Ports Scan: Quickly checks the ports most frequently targeted and used.
All Ports Scan: Performs a thorough scan of all 65,535 TCP ports for an in-depth security audit.

3. What does the “Common Ports Scan” check?

This mode scans a predefined list of common ports, such as 21 (FTP), 22 (SSH), 25 (SMTP), 80 (HTTP), 110 (POP3), 143 (IMAP), 443 (HTTPS), 3306 (MySQL), 3389 (RDP), and more. This scan is fast and ideal for routine quick security check-ups.

4. What is the “All Ports Scan” for, and why is it so slow?

This mode checks every single port from 1 to 65,535 to ensure no hidden or uncommon services are running. The process is time-consuming because it involves sending and receiving tens of thousands of requests, but it provides the most comprehensive security overview.

5. How should I interpret the scan results?

The scan results will show one of three statuses:

Open: The port is listening, a service is running, and it may pose a risk.
Closed: The port is not responding, no service is running, which is a safe state.
Filtered: The request was blocked by a firewall or network device, and the port’s status could not be determined.

6. Why does the tool automatically populate my IP address?

This is to make it easy for users to perform a security self-check on their current network environment. Scanning your own network is the most common and legitimate use of a port scanner. You can manually change the IP if you need to scan another device you are authorized to manage.

7. Is it illegal to scan ports?

Scanning network devices that you own or have explicit permission to access is completely legal and a necessary step for security hardening. However, scanning someone else’s network without permission can be considered an illegal intrusion.

8. Does a “Filtered” status mean I am safe?

A “Filtered” status indicates that a security device like a firewall is active, which is a good sign. It makes it harder for an attacker to probe your network. However, it doesn’t guarantee there’s no service behind the port, only that it’s not directly accessible from the outside.

9. Can I use this tool to check my server’s firewall configuration?

Absolutely. Using this port scanner is an excellent way to verify your firewall rules after you have configured them. You can confirm from an external perspective that the ports you intended to close are indeed showing as “Closed” or “Filtered.”

10. What should I do if I find an unexpected “Open” port?

You should take immediate action. First, investigate which application or service is using that port. If the service is not essential, you should close it immediately through your system or firewall configuration to eliminate the security risk.

Protect Your Online Identity: Beyond Port Security

Just as a port scan can reveal the “gateways” to your network, your online activities leave a digital “fingerprint” that becomes another “gateway” for websites to identify you. A browser fingerprint is composed of dozens of parameters like your OS, screen resolution, fonts, and plugins, making it highly unique.

When you manage multiple accounts from the same device, platforms can detect this association through identical browser fingerprints, which can lead to your accounts being restricted or banned.

To counter this detection, you need a professional tool. FlashID is a leading fingerprint browser that creates a completely separate and authentic virtual fingerprint environment for each browser profile. This means each of your accounts operates as if from a different, independent device, completely eliminating security issues caused by environmental association. Whether you’re in social media marketing, e-commerce, or simply want to protect your personal privacy, FlashID is your indispensable and powerful ally.