Is port scanning illegal?

Only scan systems you own or have written permission to test.

Which preset for web server?

Use Web preset (80, 443, 8080) then port checker for single ports.

Closed means nothing listening; filtered often means firewall dropped probes.

Yes. IP Checker publishes this guide and Port scanner at no cost. No account is required for standard use.

No. Open the guide’s tool link in any modern browser on desktop, tablet, or phone.

This guide explains concepts and keywords in depth. The tool page runs the live check and shows instant results.

We do not permanently store queries from these tools. Some checks run in your browser; others fetch public data for that request only.

Yes. Link to https://ipchecker.online/guides/port-scanner-guide or the tool at /tools/port-scanner.

Scan dozens of ports in one click — then verify with port checker

In-depth guide · 8 FAQs · ~1000+ words

Topics: port scanner · online port scan · tcp port scanner · scan open ports · online port scanner

Network Tools

Port Scanner

Scan common ports (21, 22, 80, 443, 3389…) on any host

443open

22closed

80open