Test an IP address or domain from multiple global probes. Compare ICMP Ping and TCP port connectivity to troubleshoot latency, packet loss, blocked routes, and unavailable services.
How it works: Ping checks ICMP response. TCP checks whether a selected service port accepts connections. A host can pass one test and fail the other.
Start a network test
How to read your results
Connection refused
Problem: The target returned Connection Refused.
Likely situation: The host is reachable, but no service is listening on the selected port, or the host firewall actively rejected the connection.
Next steps: Check the service, listening interface, port configuration, and firewall rules.
Timeout
Problem: The connection received no response before the timeout.
Likely situation: Traffic may be filtered or dropped by a firewall, route, regional network policy, unavailable service, or an unhealthy probe.
Next steps: Check firewall drop rules, routing, service health, regional behavior, and additional probes. A timeout alone does not prove that an IP is blocked.
IPv6 troubleshooting tip
Problem: The IPv6 target is unreachable or times out.
Likely situation: The server may only have a link-local address beginning with fe80::, or its IPv6 gateway, route, firewall, or ICMPv6 settings may be incomplete.
Next steps: Assign a globally routable IPv6 address, verify the gateway and route table, allow ICMPv6 where appropriate, and run the test again.
Network unreachable
Problem: The probe could not reach the target network.
Likely situation: The route, gateway, target address, or upstream network may be unavailable.
Next steps: Verify the target address, gateway, route table, network interface, and upstream connectivity.
DNS error
Problem: The hostname could not be resolved.
Likely situation: DNS records may be missing, stale, misconfigured, or unavailable from the probe location.
Next steps: Check DNS records, nameservers, TTL, DNSSEC, and resolution from the affected region.
Frequently Asked Questions
What is an online Ping test?
An online Ping test sends ICMP probes from selected locations to measure whether a host responds and how long the response takes. Some servers block ICMP even when their services are available.
What is a TCP port check?
A TCP port check attempts to establish a connection to a specific service port, such as 22 for SSH or 443 for HTTPS, from selected probe locations.
Why are the results different in Mainland China compared to other regions?
Regional firewall policies, cross-border traffic filtering, routing issues, and international ISP congestion can cause major differences. If probes in Mainland China consistently time out while probes elsewhere succeed, your IP or service is likely affected by regional network blocking. Run a fresh test from multiple locations to confirm the issue.
Why does TCP work while Ping fails?
The target may allow the service port but block ICMP requests. This is common on servers that disable Ping responses as a security policy.
Why does Ping work while TCP fails?
The host may be reachable, but the selected port may be closed, filtered by a firewall, or not running a service.
Can I test a full URL?
Yes. Paste an HTTP or HTTPS URL and the tool will remove the protocol and path, keep the hostname, and extract an explicit port when present.
Does this tool scan ports?
No. The tool checks one selected TCP port at a time. It does not perform port-range scans or flood tests.
Results are based on the listed network probes and the time shown on this page. Do not use this tool for unauthorized scanning or stress testing.
