Server Status Checker
Professional-grade website diagnostic tool. Verify server reachability, measure latency, protocol security, and visualize connectivity via direct browser-based checks.
| Time | Target | Status | Latency |
|---|
About
This Server Status Checker is a client-side diagnostic utility designed to verify the reachability and responsiveness of web servers. Unlike simple "ping" tools, this utility attempts to establish a complete HTTP/HTTPS handshake to determine if a specific domain is accessible from your current network location. This distinction is critical: a server might respond to ICMP packets (ping) but fail to serve HTTP requests due to misconfigured web server software (Nginx/Apache) or firewall rules.
The tool utilizes the fetch API with no-cors modes to bypass standard browser security restrictions, allowing it to detect the presence of a server even if the server does not explicitly allow cross-origin requests. It measures Latency (L), defined as the time delta between the request initiation (tstart) and the first byte of the response (tend). High latency often indicates network congestion, poor routing, or an overloaded server CPU.
Formulas
The core metric for server health is Network Latency. This tool calculates the Round Trip Time (RTT) using the High Resolution Time API:
Where:
Availability (A) over time is theoretically expressed as:
Reference Data
| Code | Class | Description | Typical Cause |
|---|---|---|---|
| 100 | Informational | Continue | Server has received headers and client should proceed to send body. |
| 101 | Informational | Switching Protocols | Requester has asked the server to switch protocols (e.g., HTTP to WebSocket). |
| 200 | Success | OK | Standard response for successful HTTP requests. |
| 201 | Success | Created | The request has been fulfilled and resulted in a new resource being created. |
| 204 | Success | No Content | The server successfully processed the request, but is not returning any content. |
| 301 | Redirection | Moved Permanently | This and all future requests should be directed to the given URI. |
| 302 | Redirection | Found | Commonly used for temporary redirects. |
| 304 | Redirection | Not Modified | Indicates the cached version is still available and fresh. |
| 307 | Redirection | Temporary Redirect | Connect again to different URI as provided by the Location header. |
| 400 | Client Error | Bad Request | The server cannot or will not process the request due to an apparent client error. |
| 401 | Client Error | Unauthorized | Authentication is required and has failed or has not yet been provided. |
| 403 | Client Error | Forbidden | The request was valid, but the server is refusing action (often permissions). |
| 404 | Client Error | Not Found | The requested resource could not be found but may be available in the future. |
| 405 | Client Error | Method Not Allowed | A request method is not supported for the requested resource (e.g., GET vs POST). |
| 408 | Client Error | Request Timeout | The server timed out waiting for the request. |
| 418 | Client Error | I'm a teapot | Hyper Text Coffee Pot Control Protocol (HTCPCP/1.0). |
| 429 | Client Error | Too Many Requests | The user has sent too many requests in a given amount of time (Rate Limiting). |
| 500 | Server Error | Internal Server Error | A generic error message, given when an unexpected condition was encountered. |
| 502 | Server Error | Bad Gateway | The server was acting as a gateway or proxy and received an invalid response. |
| 503 | Server Error | Service Unavailable | The server is currently unavailable (overloaded or down for maintenance). |
| 504 | Server Error | Gateway Timeout | The server was acting as a gateway and did not receive a timely response. |
| 521 | Server Error | Web Server Is Down | Specific to Cloudflare; the origin server refused the connection. |
| 522 | Server Error | Connection Timed Out | Specific to Cloudflare; could not negotiate a TCP handshake with the origin. |