Web Server Test Online Tool

Enter your domain or IP address, optionally followed by a custom port (e.g., :8080 or :8443).

Technical Details

Check connection, response headers, SSL/TLS encryption, and protocol negotiation of any Hypertext Transfer Protocol (HTTP) or HTTPS web server over IPv4 and IPv6. Verify your server's accessibility, status codes, and raw HTTP headers in real-time. By default, the test connects over standard ports 80 and 443, but you can specify a custom port by appending a colon and the port number to your target (e.g., :8080 or :8443).

Modern web servers support multiple protocol versions. HTTP/1.1 establishes a standard text-based connection, while HTTP/2 introduces binary framing and multiplexing, allowing multiple concurrent streams over a single TCP connection to significantly reduce latency. Select your desired protocol version before running the test to explicitly force the connection and verify your target server's compatibility.

For secure HTTPS connections, the test performs a standard SSL/TLS handshake using Server Name Indication (SNI) to verify if the server accepts encrypted traffic. It reveals the Application-Layer Protocol Negotiation (ALPN) data, such as h2 or http/1.1. ALPN strictly requires a valid SSL certificate and TLSv1.2 or newer. While this tool can test unencrypted HTTP/2 connections (h2c), it is rarely used in production since all major web browsers support HTTP/2 exclusively over encrypted ALPN. Self-signed certificates are fully supported by this test.

It uses curl to perform a HEAD query, efficiently fetching the raw HTTP response headers without downloading the entire payload body. This works seamlessly for testing Apache, Nginx, IIS, LiteSpeed, Content Delivery Networks (CDN), load balancers, REST APIs, and any HTTP/HTTPS service in general. The network test is considered successful if it receives a valid HTTP status code (such as 200 OK, 301 Moved Permanently, or even a 403 Forbidden), confirming that the web server is reachable and actively responding to requests.

HTTP Response Interpretation

The output console displays the raw HTTP response headers returned by your target server. Analyzing these headers is the most effective way to diagnose redirection loops, caching policies, and protocol upgrades. Use the following guide to understand the key fields:

Status Line: The first line (e.g., HTTP/1.1 200 OK or HTTP/2 301 ) indicates the negotiated protocol version and the exact outcome of the request. Note that HTTP/2 headers are strictly formatted in lowercase by the protocol's design.
Location: Used strictly during redirects (such as 301 or 302 status codes) to instruct the client where to route the traffic, commonly used to force an HTTPS connection.
Upgrade & Connection: Indicates the server's readiness to switch to a more modern, multiplexed protocol, such as upgrading from standard HTTP/1.1 to HTTP/2 (h2 or h2c).
Server: Identifies the underlying web server software (e.g., Apache, Nginx, IIS) generating the response.
Cache-Control & Expires: Define the caching directives, instructing browsers and Content Delivery Networks (CDNs) on how long they should store the resource locally to improve load times.
Content-Type & Date: Content-Type specifies the media format and character encoding (e.g., utf-8 or iso-8859-1) , while Date records the exact server timestamp when the response was generated.

Common Connection Issues

The following steps may help you pass this test in case of trouble:

Verify that your web server service (e.g., Apache, Nginx, IIS) is actively running and bound to the correct network interfaces.
Verify that the domain's DNS is resolving to the correct IP addresses (A or AAAA records), if you're entering a hostname.
Verify that your server's TCP ports 80 (HTTP), 443 (HTTPS), or the specific port entered in the URL are accessible from this website's IPv4 and IPv6 addresses: 173.249.29.54 and 2a02:c207:1:3253:1::1
Verify that your SSL/TLS certificate is valid, not expired, and properly configured for the requested domain name (SNI).
Verify that your Web Application Firewall (WAF), CDN, or rate-limiting software is not actively dropping or blocking our diagnostic requests.

Save Your Results

You can optionally save your results and share them with your team as evidence for troubleshooting tickets, scientific documentation, IT compliance audits, or any other purpose. This helps satisfy the strict evidence and network monitoring requirements of major cybersecurity frameworks such as ISO 27001, SOC 2, PCI DSS, and HIPAA. We commit to storing your results for a minimum period of 5 years and a maximum of 10 years, after which the saved results are permanently deleted from our servers.

Related Resources

Explore our complete suite of diagnostic tools for system administrators and webmasters. All tests are securely executed from a high-performance Debian virtual private server using industry-standard open-source software: