How to Find Open Ports on a Server [2026]

Enterno.io Editorial Team

How to Check Which Ports Are Open on a Host

By Anatoly Oshmanovsky · Updated Apr 17, 2026

TL;DR:

To check open ports: Enterno.io port-checker — enter host and port, get status (open/closed/filtered) in 1-2 seconds. For a full scan (top-100 ports) use the Port Scanner.

Try it now — free →

Step-by-step guide

Open the port checker. Go to enterno.io/en/ping.
Enter host and port. Example: example.com + 443. IPv4, IPv6, hostname — all supported.
Run the check. Result: open (port listening), closed (connection refused), filtered (firewall blocking).
For a full scan — Port Scanner. At /en/port-scanner you can check the top-100 ports + a custom list in one pass.
Locally: nmap / nc. From the command line: nc -zv hostname 443 or nmap -p 22,80,443 hostname. Online checker is simpler and checks from varied IPs.

Open tool →

ICMP PingHost availability and latency

Port ScannerOpen TCP port detection

LatencyResponse time in milliseconds

Packet LossPercentage of dropped packets

Why teams trust us

ICMP+TCP

check protocols

key ports scanned

<2s

result

regions

How it works

Enter IP or domain

ICMP packets sent

Latency & packet loss shown

How Do Ping and Port Scanning Work?

Ping sends ICMP packets to a host and measures response time. Port scanning checks which TCP ports are open and accepting connections — helping diagnose serviceavailability issues.

Configurable Ping

Choose packet count (3, 4, 6, 10). Stats: min/avg/max latency and packet loss.

Common Port Scanner

Check 14 key ports: HTTP, HTTPS, SSH, FTP, SMTP, MySQL, PostgreSQL, and more.

Cloud-Based Check

Testing from our server — see site availability from outside, not just your local network.

Uptime Monitoring

Need constant monitoring? Create a monitor — checks every minute with notifications.

Who uses this

DevOps

availability diagnosis

Network engineers

TCP port scanning

Developers

connection debugging

SRE

basic health check

Common Mistakes

❌

ICMP blocked = server is downMany servers block ICMP. Ping fails but site works — check ports instead.

❌

High ping = server problemLatency depends on geography. 150ms between continents is normal, not an error.

❌

Closed ports — cause for alarmClosed ports of unused services are good. Unnecessary open ports are a risk.

❌

One check = sufficientNetworks are unstable. A single timeout ≠ a problem. Check multiple times or set up monitoring.

Best Practices

✓

Combine ping and port checksPing shows host availability, ports show specific service availability. Use both.

✓

Check from different locationsThe problem may be local. A cloud test shows the real picture.

✓

Close unused portsEvery open port is a potential attack vector. Keep only necessary ports open.

✓

Set up monitoringManual checks do not scale. Set up automated monitoring with notifications.

Get more with a free account

Ping check history, host availability monitoring and downtime alerts.

Learn more

Research

Open Port Exposure in Runet 2026

Alternatives

Frequently Asked Questions

Is signup required?

For a quick check (1-2 requests/min) — no. For continuous monitoring — free account. No credit card.

Is this free?

Yes. Enterno.io Scout is a forever-free plan with 5 monitors. All basic tools without signup.