Port Scanner

Scan common ports on any IP address. Check if services are running and accessible — useful for network diagnostics.

How to use the Port Scanner

1

Enter the target host

Type an IP address (e.g. 192.168.1.1) or hostname (e.g. example.com) into the input field. The Port Scanner accepts both IPv4 addresses and domain names.

2

Choose which ports to scan

Select from common ports (HTTP, HTTPS, SSH, FTP, SMTP, DNS), well-known service ports, or specify a custom port range. Defaults cover the 20 most useful service ports.

3

Run the scan

Click "Start Scan". The tool probes each port using standard TCP connection attempts and reports whether each is open, closed, or filtered by a firewall. Scans usually complete in 5-15 seconds.

4

Interpret the results

Each port shows its status (open/closed/filtered), the service name, and the typical use. Use this for legitimate network diagnostics, security audits of your own systems, or troubleshooting connectivity.

Pro tips

  • Only scan systems you own or have explicit permission to test — unauthorized port scanning can violate computer-misuse laws in many jurisdictions.
  • Run the scan from outside your network to verify firewall rules match your intent.
  • Compare results before and after firewall changes to confirm ports are blocked.
  • Open ports are not inherently dangerous — what matters is whether the listening service is patched and properly configured.

Key features

  • 100% Free
    No signup, no credit card, no hidden limits.
  • Privacy First
    All processing happens in your browser — your data never leaves your device.
  • Instant Results
    Process in seconds with no uploads, no waiting, no server delays.
  • Works Offline
    Once loaded, the tool works without an internet connection.

About the Port Scanner

The Port Scanner is part of LaiUse's growing collection of network tools, ip lookup, dns, whois, ssl checker. Like every tool on LaiUse, it runs entirely in your browser — meaning your data, files, and inputs stay on your device throughout the entire process.

LaiUse offers Network tools alongside speed test, dns lookup, ipv4 calculator. The entire platform is free to use with no signup required, making it a popular choice for developers, designers, and everyday users who need a quick tool without the overhead of a SaaS subscription.

Whether you need the port scanner for a one-off task or as part of your regular workflow, LaiUse is designed to be fast, reliable, and private. Bookmark this page to come back anytime, or explore the rest of the Network category for related tools.

Frequently asked questions

Is this tool free to use? +

Yes. The Port Scanner is free to use without an account. Most LaiUse tools have no limits and run entirely in your browser; the Port Scanner runs the probe from LaiUse servers and is available to all users.

Is port scanning legal? +

Port scanning is legal when performed on systems you own or have explicit written permission to test. Unauthorized scanning of third-party systems may violate computer-misuse laws (e.g. the US Computer Fraud and Abuse Act, the UK Computer Misuse Act, Singapore Computer Misuse Act). Always get permission first.

Why do some ports show as "filtered"? +

A filtered port means a firewall or network device is actively blocking the probe, so the scanner cannot determine whether the port is open or closed. This is normal and not necessarily a sign of a problem.

Can I scan IPv6 addresses? +

The Port Scanner currently supports IPv4 addresses and hostnames that resolve to IPv4. IPv6 scanning is on the request list — use the Request a Tool page to upvote it.

Related Network tools

Speed Test
Test your internet connection speed. Measure download and upload bandwidth with a simple b...
DNS Lookup
Look up DNS records for any domain. Query A, AAAA, MX, TXT, CNAME, and NS records instantl...
IPv4 Calculator
Calculate IPv4 subnets, CIDR notation, and IP ranges. Subnet calculator for network engine...