Debug API responses
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HTTP Status Code Lookup
The HTTP status code lookup explains common HTTP response codes such as 200, 201, 301, 400, 401, 403, 404, 409, 422, 429, and 500. It is built for quick API debugging and documentation checks.
Status codes are small, but they carry important meaning. A 401 usually points to authentication, a 403 to authorization, a 404 to a missing route or resource, and a 429 to rate limiting.
HTTP status code lookup
Look up common HTTP status codes and debugging notes.
What this tool does
HTTP status codes summarize what happened to a request. They are the first clue when debugging APIs because they separate success, redirects, client errors, and server errors before you even inspect the response body.
This lookup tool explains common status codes in practical terms. It helps you quickly distinguish authentication problems, authorization failures, missing resources, validation errors, rate limits, and server-side failures.
Common use cases
Write better documentation
Clarify what response codes mean for endpoint behavior.
Triage errors quickly
Use the code family to decide whether to check request input, authentication, or server logs.
Example before and after
A status code points you toward the likely category of problem before deeper debugging.
Status code
429Meaning
Too Many Requests. The client has sent too many requests in a given time window.How to use
- Enter an HTTP status code.
- Click Look Up Status.
- Read the meaning, category, and debugging note.
Common errors
Confusing 401 and 403
401 is about authentication. 403 is about permission after authentication.
Ignoring response bodies
The status code is a summary; the body often contains the specific error reason.
Treating every 500 as permanent
Some server errors are transient, while others need code or configuration fixes.
Why use this tool
Debug API responses faster.
Clarify status codes in documentation.
Understand error categories at a glance.
Best practices
Start with the status family
2xx, 3xx, 4xx, and 5xx categories quickly narrow the debugging path.
Read headers too
Headers can explain rate limits, caching, redirects, and authentication.
Document expected codes
Good API docs describe success and error responses explicitly.
Related tools
Related guides
HTTP status codes explained
HTTP status codes quickly tell you whether a request succeeded, redirected, failed client-side, or failed server-side.
How to read HTTP headers
HTTP headers carry metadata that explains how an API response should be parsed, cached, authenticated, and traced.
Best practices for working with API responses
API responses are easier to debug when you validate syntax, format payloads, inspect errors, and compare changes deliberately.
FAQ
What is a 2xx status?
2xx codes usually mean the request succeeded.
What is the difference between 401 and 403?
401 means authentication is missing or invalid. 403 means the authenticated caller is not allowed.
Does 500 always mean my request is wrong?
No. 5xx responses usually indicate server-side or upstream failures.
Does this call an API?
The tool runs in your browser and does not require login, a database, or server-side processing.