Port Checker
Check if a specific port is open or closed on any server. Use preset buttons for common ports or enter custom port numbers.
Quick presets:
Common Ports Reference
| Port | Service | Description |
|---|---|---|
| 20 | FTP Data | File Transfer Protocol data transfer |
| 21 | FTP Control | File Transfer Protocol command control |
| 22 | SSH | Secure Shell remote access |
| 23 | Telnet | Unencrypted remote access (deprecated) |
| 25 | SMTP | Simple Mail Transfer Protocol |
| 53 | DNS | Domain Name System queries |
| 80 | HTTP | Hypertext Transfer Protocol (web) |
| 110 | POP3 | Post Office Protocol v3 (email) |
| 143 | IMAP | Internet Message Access Protocol (email) |
| 443 | HTTPS | HTTP Secure (encrypted web) |
| 465 | SMTPS | SMTP over SSL |
| 587 | SMTP-TLS | SMTP with STARTTLS |
| 993 | IMAPS | IMAP over SSL |
| 995 | POP3S | POP3 over SSL |
| 3306 | MySQL | MySQL database server |
| 3389 | RDP | Remote Desktop Protocol |
| 5432 | PostgreSQL | PostgreSQL database server |
| 6379 | Redis | Redis in-memory data store |
| 8080 | HTTP Alt | Alternative HTTP port |
| 27017 | MongoDB | MongoDB database server |
Frequently Asked Questions
How do I check if a port is open?
Enter the hostname or IP address and the port number you want to check, then click 'Check Port'. Our tool will attempt to connect to the specified port and report whether it is Open, Closed, or Filtered/Timeout. You can also check multiple ports at once by entering comma-separated port numbers.
What are the most common ports?
The most common ports include: HTTP (80), HTTPS (443), FTP (21), SSH (22), SMTP (25/587), DNS (53), POP3 (110), IMAP (143), MySQL (3306), PostgreSQL (5432), Redis (6379), MongoDB (27017), and RDP (3389). Each port is associated with a specific service or protocol.
Why is my port closed?
A port may appear closed for several reasons: the service is not running on that port, a firewall is blocking the connection, the server is configured to reject connections on that port, or network address translation (NAT) is preventing external access. Check your firewall rules, ensure the service is running, and verify port forwarding settings if applicable.