search

Found

info About

A quick reference and search tool for common network port numbers and services.

📘 How to Use

  1. Search by port number (e.g., 443) or service name (e.g., MySQL).
  2. Check the usage, protocol, and notes from the list.
  3. Use the “Check Local” button to verify listening ports on your local environment.

Port Checker & Dictionary

Port Checker & Service Dictionary

Quickly identify common network ports and services.

Port Service Description Action

Note: Browser security policies (port restrictions, etc.) may limit connection tests. Note:"Check" functionality tests local availability from your browser and may be restricted by security policies.

grid_view Related

  • No related tools configured.
Article

Identify Network Ports & Services Instantly | Port Dictionary 🌐

Map network port numbers to protocols in seconds. Search by port or service name to understand your network traffic and local environment.

💡 About This Tool

Decode firewall logs and netstat outputs without the guesswork. This tool provides a fast, searchable reference for well-known and registered ports.

Whether you're a sysadmin hardening a server, a developer debugging a local environment, or a student learning networking, use this dictionary to identify protocols instantly. Use the Localhost Check feature to verify if a service is actively responding on your machine.

📘 Pro Tips

  • Search Flexibly Filter by number (e.g., "80") or keyword (e.g., "SQL", "Secure") to find all related services.
  • Verify Local Services Click the Check Localhost button to test if a port is responding on your machine—the fastest way to confirm your dev server is live.
  • Identify Modern Dev Ports Access a database that includes modern development ports like 3000 (React/Node.js) and 6379 (Redis) alongside traditional networking standards.

🧐 Frequently Asked Questions

  • Why is the Localhost Check result uncertain? Browsers enforce strict security policies that block requests to sensitive ports (like 22 for SSH or 25 for SMTP) to prevent cross-site attacks. For these ports, the check may fail even if the service is running.
  • Are all 65,535 ports listed? No. We focus on the "Well-Known" and "Registered" ports you are most likely to encounter to keep the tool fast and relevant.

📚 Trivia: Why 65,535?

Port numbers are 16-bit unsigned integers. This limits the range from 0 to 2^16 - 1, which equals 65,535. While an IP address directs data to the right computer, the port number ensures that data reaches the specific software application intended to receive it.