Reference
Search by code or meaning, filter by response class, and keep the selected status explanation visible while you debug APIs, retries, redirects, or user-facing errors.
Best use case
This works best when you need a quick status lookup during API debugging, response handling, or backend contract work without digging through long RFC pages first.
404
Not Found
What it means
The requested resource could not be found on this server.
Response class
4xx Client Error
Lookup result
26 codes in view
How to Use This Http Status Codes Reference
Search by number or meaning, narrow the list by response class if needed, then keep the selected status explanation visible while you work through the issue.
Search by code or phrase
Use a number like 404 or a phrase like rate limit, forbidden, or redirect to quickly narrow the list.
Filter by response class if needed
Switch between 1xx, 2xx, 3xx, 4xx, and 5xx when you want to focus on one part of the HTTP response space.
Select the exact status code
Keep the selected code open on the right while you compare meaning, category, and likely behavior.
Use the definition in your debugging flow
Apply the meaning to API design, client handling, retries, redirects, or user-facing error messages.
When This Tool Is Most Useful
It helps most when you are actively debugging a response or deciding what a backend should return and want something faster than digging through long standards docs.
API debugging
Check whether the response code you are seeing actually matches the problem your client or server is reporting.
Error handling design
Use the reference when deciding which client states should retry, which should re-authenticate, and which should surface a user-facing error.
Backend and contract work
Pick the most accurate status code when shaping a REST or HTTP-style API instead of defaulting everything to 200 or 500.
Operational monitoring
Review what a code means before you wire alerts, dashboards, or incident thresholds around it.
FAQs
What is this reference best for?+
It is best for fast lookup while debugging APIs, reviewing response behavior, or deciding how a server should respond to a request.Why keep category filters in the tool?+
They make large status-code lists easier to scan, especially when you are focusing only on client errors or server failures.Does this replace the RFCs?+
No. It is a fast working reference. The RFCs still matter for full standards detail and edge-case behavior.Why is a 4xx different from a 5xx in practice?+
A 4xx usually points to a client-side or request problem, while a 5xx usually signals a server-side failure or unavailable dependency.