T Online Tools
Home / Network

HTTP Status Codes

Reference for all HTTP status codes

What is HTTP Status Codes?

HTTP Status Codes is a free online tool that helps you reference for all http status codes. It runs entirely in your browser using client-side JavaScript, so your data stays private and never leaves your device.

When to Use

  • Troubleshooting network issues and looking up DNS or IP information
  • Learning about networking concepts like ports, protocols, and headers
  • Quick reference for network configuration and diagnostics

How to Use

Enter your input in the field above, adjust any settings if available, and click the action button. Results appear instantly—no page reload, no server wait. All processing happens locally in your browser.

Related Tools

Try our HTTP Status Code Reference for related functionality.

Deep Dive: How HTTP Status Codes Works

HTTP Status Codes provides instant visibility into network configuration, connectivity, and protocol details—essential diagnostic capabilities for anyone working with internet-connected systems. Network troubleshooting is notoriously difficult because problems can originate anywhere in the stack: DNS misconfiguration, routing issues, firewall rules, application-level bugs, or upstream provider outages. HTTP Status Codes helps you quickly narrow down the source of issues by providing key diagnostic data points without requiring SSH access to remote servers or installation of specialized network tools. Understanding your network environment is also critical for security—knowing what's exposed, what IP information you're leaking to services, and what ports are accessible helps you assess your attack surface and implement appropriate protections. For developers building web applications, network tools provide the ground truth needed to debug connectivity issues, verify CDN configuration, and ensure APIs are reachable from production environments.

Pro Tips

  • Check DNS from multiple locations if results seem wrong—DNS propagation can take up to 48 hours
  • Use IP lookup tools to verify your VPN or proxy is actually routing traffic correctly
  • Test port connectivity before blaming application code—firewall rules are the most common culprit

Common Mistakes to Avoid

  • Trusting a single IP lookup source—geolocation databases have varying accuracy
  • Testing connectivity only from your own machine when users are on different networks

Frequently Asked Questions

What does HTTP status code 404 mean and how do I fix it?
HTTP 404 means 'Not Found'—the server can't find the requested resource. Check for typos in the URL, verify the page hasn't been moved or deleted, set up 301 redirects for renamed pages, and create a custom 404 error page to help visitors find what they're looking for.
What's the difference between HTTP 301 and 302 redirects for SEO?
A 301 redirect is permanent and passes 90-99% of link equity (PageRank) to the new URL—use it when you've permanently moved a page. A 302 redirect is temporary and doesn't pass link equity—use it for A/B testing or temporary maintenance. Search engines treat them very differently for indexing.
What do HTTP 2xx, 3xx, 4xx, and 5xx status code ranges mean?
2xx (200-299) = Success—the request was received and processed. 3xx (300-399) = Redirection—further action is needed. 4xx (400-499) = Client error—the request has an issue (bad URL, unauthorized). 5xx (500-599) = Server error—the server failed to fulfill a valid request.