📖 HTTP Status Codes Lookup
Find status codes by number or phrase and understand when to use each one.
Select a status code
Use search or click a code from the list.
What is an HTTP Status Code Lookup Tool?
An HTTP status code lookup tool helps you quickly interpret response codes returned by web servers and APIs. Every HTTP response has a numeric status code such as 200, 404, or 503. That number tells clients whether the request succeeded, failed, should be retried, or needs authentication. During debugging, logging, and API development, fast interpretation of these codes saves time and reduces mistakes.
Status codes are grouped into classes: 1xx informational, 2xx success, 3xx redirection, 4xx client errors, and 5xx server errors. While many developers know common codes like 200 and 404, production systems often rely on less common responses such as 206, 304, 409, 422, or 429. Understanding the nuance helps you design better error handling, retry logic, and user messaging.
This tool lets you search by code or phrase, filter by class, and view practical usage notes for each response. It also gives a copy-ready protocol line like "HTTP/1.1 429 Too Many Requests" for tests, mock servers, and docs. Everything works client-side in your browser.
How to Use This Tool
- Type a code or keyword in search, for example 401, timeout, or forbidden.
- Optionally filter by class to narrow results to 2xx, 4xx, and so on.
- Click a result to view meaning, common use, and caching notes.
- Use the Jump field if you already know the exact code number.
- Copy the HTTP status line for examples, docs, or tests.
Key Features
- Search by code number or response phrase.
- Filter by HTTP status class from 1xx through 5xx.
- Detailed usage notes for APIs and browser workflows.
- Copyable protocol status line for quick testing.
- No backend needed, all lookup logic is local.
Frequently Asked Questions
What is the difference between 401 and 403?
401 means authentication is required or failed. 403 means the client is authenticated but not allowed to access the resource.
When should I use 404 vs 410?
Use 404 when a resource cannot be found and its state is unknown. Use 410 when a resource is intentionally and permanently gone.
What does 429 indicate?
429 means rate limiting. The client sent too many requests in a given time window and should back off before retrying.
Should 5xx errors be retried?
Often yes, with exponential backoff and limits. It depends on idempotency and whether the operation can be safely repeated.