HTTP Status Codes
Reference guide for all HTTP status codes.
Continue
Server received request headers, client should proceed to send the body.
Switching Protocols
Server agrees to switch protocols per the client's Upgrade header.
OK
Request succeeded. The response body contains the result.
Created
Request succeeded and a new resource was created.
No Content
Request succeeded but no response body.
Partial Content
Partial resource returned (range requests).
Moved Permanently
Resource permanently moved to a new URL.
Found
Resource temporarily at a different URL.
Not Modified
Cached resource is still valid. Client should use cache.
Temporary Redirect
Redirect with same HTTP method.
Permanent Redirect
Permanent redirect preserving the HTTP method.
Bad Request
Server cannot process the request due to client error.
Unauthorized
Authentication required. Client must authenticate first.
Forbidden
Server understood request but refuses to authorize it.
Not Found
Resource not found at the given URL.
Method Not Allowed
HTTP method is not allowed for this resource.
Request Timeout
Server timed out waiting for request from client.
Conflict
Request conflicts with current state of the resource.
Gone
Resource permanently deleted and will not be available again.
Payload Too Large
Request body exceeds server's size limits.
URI Too Long
Request URI is too long for the server to process.
Unsupported Media Type
Request media type is not supported by the server.
Unprocessable Entity
Request is well-formed but contains semantic errors.
Too Many Requests
Client has sent too many requests (rate limiting).
Internal Server Error
Server encountered an unexpected condition.
Not Implemented
Server does not support the requested functionality.
Bad Gateway
Upstream server returned an invalid response.
Service Unavailable
Server temporarily unavailable (overloaded or down).
Gateway Timeout
Upstream server failed to respond in time.
How to use HTTP Status Codes
Enter or search a status code
Click the search bar at the top of the tool and type the HTTP status code number (e.g., 404, 500, 200). Alternatively, scroll through the categorized list organized by code ranges in the left sidebar.
Review the detailed status information
View the status code, official name, HTTP category, and plain-English meaning in the main results panel. Each entry displays the official RFC definition and common use cases.
Check related codes and solutions
Expand the 'Related Codes' section below to see similar status codes. Read the 'What It Means' and 'Common Causes' tabs to understand why this status code appears.
Copy or bookmark results
Click the 'Copy' button next to any code definition to copy to clipboard. Use the bookmark icon in the top-right corner to save frequently referenced codes to your browser.
Complete HTTP Status Codes Guide — Free Lookup Tool & Reference (2026)
HTTP status codes are three-digit numbers that servers send in response to client requests. Understanding them is essential for web developers, DevOps engineers, and anyone troubleshooting website issues. This guide explains all major codes and how to use our free HTTP Status Codes reference tool.
What Are HTTP Status Codes?
HTTP status codes are standardized responses from web servers that tell clients (browsers, applications, APIs) the outcome of their request. They range from 100 to 599, organized into five categories. Every time you visit a website, upload a file, or call an API, you receive a status code that determines what happens next.
The 5 Categories of HTTP Status Codes
1xx (Informational): Provisional responses indicating the request was received and processing continues. Example: 100 Continue.
2xx (Success): The request succeeded. 200 OK is the most common, meaning the request completed successfully and the server returned the requested resource.
3xx (Redirection): The client must take additional action to complete the request. 301 Moved Permanently and 302 Found redirect users to new locations.
4xx (Client Error): The client sent a malformed request. 404 Not Found (page doesn't exist) and 403 Forbidden (access denied) are most common.
5xx (Server Error): The server failed to fulfill a valid request. 500 Internal Server Error and 503 Service Unavailable indicate server-side problems.
Most Common HTTP Status Codes
200 OK: Request succeeded; server returns requested data. This is the ideal response for successful GET, POST, and PUT requests.
301 Moved Permanently: Indicates permanent URL change. Search engines update their indexes, and browsers cache this for future requests.
302 Found: Temporary redirect. Used when content moves briefly or during maintenance. Browsers don't cache this.
304 Not Modified: Cached content is still valid. Saves bandwidth by telling the client to use its cached version.
400 Bad Request: Server received malformed syntax it cannot understand. Usually caused by invalid query parameters or headers.
401 Unauthorized: Authentication required but not provided. User must log in with credentials.
403 Forbidden: Server understood request but refuses to authorize it. Access denied even with correct credentials.
404 Not Found: Requested page or resource doesn't exist. Appears when a URL is broken or content is deleted.
500 Internal Server Error: Generic server error indicating an unhandled exception. The server encountered an unexpected condition.
503 Service Unavailable: Server temporarily cannot handle requests, usually during maintenance or due to high traffic.
How to Use Our Free HTTP Status Codes Tool
Step 1: Access the tool — No installation or registration needed. Just open the tool in any web browser.
Step 2: Search for a code — Enter a status code (e.g., 404) or its name (e.g., Not Found) in the search bar. Results appear instantly.
Step 3: Review detailed information — Read the official meaning, common causes, and typical scenarios for that code.
Step 4: Check related codes — Explore similar codes to understand the broader context and differences.
Step 5: Copy or save results — Use the copy button to grab definitions for documentation or save codes you frequently reference.
Practical Tips for Using Status Codes
Monitor your website's status codes using Google Search Console or server logs to identify broken pages or redirect issues.
Implement proper redirects using 301 for permanent moves and 302 for temporary redirects to maintain SEO and user experience.
Handle errors gracefully by showing custom error pages for 4xx codes and investigating 5xx errors immediately.
Test API endpoints by checking status codes in response headers to ensure your integrations work correctly.
Cache strategically using 304 Not Modified responses to reduce bandwidth and improve page load times.
Why Status Codes Matter for SEO
Search engines respect status codes when crawling your site. Using correct codes (200 for live pages, 301 for permanent moves, 410 for deleted content) helps Google understand your site structure. Excessive 4xx or 5xx errors signal crawl problems that hurt indexing and rankings.
Common Mistakes to Avoid
Don't use 302 instead of 301 for permanent redirects—this confuses search engines about which URL should rank.
Don't return 200 OK on error pages—use appropriate 4xx or 5xx codes so clients and crawlers recognize the problem.
Don't ignore server errors—5xx codes indicate real problems that need investigation and fixing.
Don't redirect excessively—each redirect adds latency and can cause redirect chains that harm performance.
Conclusion
HTTP status codes are fundamental to how the web works. Whether you're a developer debugging API issues, a DevOps engineer monitoring server health, or a digital marketer checking site crawlability, understanding these codes saves time and prevents problems.
Our free HTTP Status Codes tool makes reference lookups instant and effortless. Bookmark it for quick access whenever you need to understand what a status code means or find the right code for your use case. No registration required—just search, learn, and apply.