Port Checker
Check whether a port is open on any host. Quick test for common ports right in your browser.
Port 443 — HTTPS: Secure encrypted web traffic (TLS).
How to use
- 1
Enter a hostname or IPv4 address and the port you want to check.
- 2
Use the common port chips to fill in well-known ports like 80, 443 or 8080.
- 3
Click Check Port — the result and response time appear instantly. No data leaves your browser.
Free Online Port Checker — Test if a TCP Port Is Open
Check whether a TCP port is open on any host directly from your browser. Fast, free and private port testing for HTTP, HTTPS and common web ports.
A port checker tests whether a given TCP port is reachable on a remote host. It's a handy tool when configuring a web server, opening firewall rules, debugging port forwarding on a router, or simply confirming that a service is online and accepting connections from the public internet.
Modern browsers only allow outbound connections to HTTP-class ports for security reasons, which means this tool can directly test ports 80, 443 and 8080. For other ports like SSH (22), FTP (21), MySQL (3306) or Remote Desktop (3389), the browser blocks the connection regardless of whether the port is actually open — we clearly flag those ports so you don't get misleading results.
Everything runs locally in your browser. No host, port or result is ever sent to or stored on our servers. For full TCP scanning across any port, use a dedicated desktop tool like Nmap or a server-side scanner.
Frequently Asked Questions
What is a port and why would I check it?
A port is a numbered endpoint a service listens on (web servers use 80 and 443, SSH uses 22, and so on). Checking a port confirms a service is reachable from outside your network — useful for setup, firewall rules and port forwarding.
Why can't I test SSH, FTP, MySQL or RDP from the browser?
Browsers block outbound connections to non-HTTP ports as a security measure. Any result from the browser would be inaccurate, so we disable testing for those ports and recommend a desktop scanner like Nmap instead.
Is this Port Checker private?
Yes. The check runs entirely in your browser using a fetch request to the host you entered. We do not log, store or share the host, port or result on our servers.
What does a CLOSED result mean?
CLOSED means the browser couldn't establish a TCP connection within the timeout — the port is either not listening, blocked by a firewall, or unreachable from your network. An OPEN result means the host responded on that port.
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