How to Test Website Uptime
Testing website uptime means sending an HTTP request to a URL and evaluating the response. A healthy website returns a 200 status code within a reasonable time (under 1 second for most sites). This tool performs that check from our server and reports the results, including response time, HTTP status, and security headers.
What the Results Mean
Status code 200 means the site responded successfully. Codes in the 300 range indicate redirects (common and usually fine). 400-range codes mean client errors (404 = not found, 403 = forbidden). 500-range codes indicate server errors, meaning something is broken on the server side.
One-Time Check vs Continuous Monitoring
This tool is great for spot-checking a URL right now. But websites go up and down unpredictably. For actual uptime monitoring, you need a tool that checks continuously and alerts you when something fails. Use the uptime calculator to understand how check frequency affects your SLA compliance.
Frequently Asked Questions
What does this uptime checker do?
It sends an HTTP request to any URL and reports the response status code, response time, and security headers. This tells you whether a website or API is currently reachable and how fast it responds.
Is this the same as uptime monitoring?
No. This is a one-time check. Uptime monitoring runs checks continuously (every 10 seconds to 5 minutes) and alerts you when something goes down. This tool is useful for quick spot-checks. For continuous monitoring, you need a tool like Warden.
Why is the response time high?
The response time includes DNS resolution, TCP connection, TLS handshake, and the HTTP request/response. Cold requests (first visit) are typically slower. Geographic distance between the checker server and the target also affects latency.
What security headers should my site have?
Strict-Transport-Security (HSTS) forces HTTPS. Content-Security-Policy prevents XSS attacks. X-Frame-Options prevents clickjacking. X-Content-Type-Options prevents MIME-sniffing. Referrer-Policy controls referrer information. All production sites should have at least HSTS and X-Content-Type-Options.
Can I check internal or private URLs?
No. For security reasons, this tool blocks requests to localhost, private IP ranges (10.x, 192.168.x, 172.x), and .local domains. Use local tools like curl for internal checks.