Dev
HTTP Status Code Reference Generator
Choosing the wrong HTTP status code is one of those API design mistakes that compounds over time — consumers write client code around the wrong semantics, and fixing it later is a breaking change. When you are designing a response or reviewing an API spec, a quick lookup that pairs the code with its precise meaning and correct name is faster than scanning the RFC. This tool returns one status code from a curated set of 16, paired with its official name and a clear plain-English explanation. Use the class filter to focus on a specific family: 2xx for success, 3xx for redirects, 4xx for client errors, or 5xx for server errors. Leave it on any for a random draw from the full set. Generate a few codes at the start of a design session to sharpen the semantics before you write the first endpoint. Use the 4xx class to settle debates about whether a bad request deserves a 400 or a 422, or whether an expired token should be 401 or 403. Each description is written to be unambiguous and actionable.
How to use
- Choose your options above
- Click Generate
- Copy your result
Detailed instructions
- Choose a status class, or leave it on any.
- Click Generate to produce a code and meaning.
- Use it to learn or to pick a response code.
- Generate again for another code.
Use Cases
- •Learning what HTTP status codes mean
- •Choosing the right code for an API response
- •Debugging an unexpected response code
- •Quizzing yourself on HTTP codes
- •Looking up a code's correct meaning
Tips
- →Learn the families: 2xx, 3xx, 4xx, 5xx.
- →Use 401 for "who are you", 403 for "not allowed".
- →Return the most specific accurate code.
- →Pair codes with a clear response body.
FAQ
what do the status code classes mean
The first digit groups codes into families: 2xx means success, 3xx means redirection, 4xx means a client error like a bad or unauthorised request, and 5xx means a server error. Knowing the family tells you who is at fault at a glance.
how many codes does this tool cover
The tool has 16 codes across four classes: four 2xx (200, 201, 202, 204), four 3xx (301, 302, 304, 307), five 4xx (400, 401, 403, 404, 429), and four 5xx (500, 502, 503, 504). Each is paired with its official name and a plain-English description.
what is the difference between 401 and 403
401 Unauthorized means authentication is missing or has failed — the server does not know who you are. 403 Forbidden means you are authenticated but not allowed to access the resource. In short: 401 is "who are you", 403 is "you may not".
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