HTTP Status Codes

What is this tool?

This HTTP status codes reference is a free, searchable table of common response codes returned by web servers and APIs. Each row shows the numeric code, the official name (e.g. Not Found), and a short description. Expand a row to read API-oriented usage notes, optional tips, and a link to MDN. You can search by code number, name, description, or text inside those API notes, and filter by class (1xx–5xx). Use it when debugging APIs, curl, fetch, or browser Network tabs—no sign-up required.

HTTP status codes are three-digit numbers defined by standards such as RFC 9110. They tell clients whether a request succeeded, was redirected, failed due to client input, or failed on the server. Understanding 404 meaning, 500 error, http 200, and rest api status codes is essential for backend and frontend developers.

Why use this reference?

Developers and operators use a status code list or HTTP status codes cheat sheet to interpret responses without opening the spec. This page groups codes by class, explains each in plain language, and stays fast in the browser—ideal next to a terminal or IDE when you ask "what does this response code mean?"

• Look up codes from REST APIs, GraphQL gateways, or static file servers
• Debug 4xx vs 5xx to decide whether to fix the client request or the server
• Onboard teammates with a single, searchable response codes reference

Status code classes (1xx–5xx)

Codes are grouped by the first digit:

• 1xx — Informational — Request received; processing continues (rare in many APIs).
• 2xx — Success — The request was understood and accepted. 200 OK and 201 Created are common.
• 3xx — Redirection — Further action needed (e.g. moved resource). Clients often follow Location automatically.
• 4xx — Client errors — Bad request, auth, or permissions. 404 Not Found and 401 Unauthorized are typical; fix the request or credentials.
• 5xx — Server errors — The server failed to fulfill a valid request. 500 Internal Server Error and 503 Service Unavailable indicate server-side issues.

Key features

• Search — Filter by code number, name, description, or expandable API usage and tips.
• Class filter — Show only 1xx, 2xx, 3xx, 4xx, or 5xx, or all classes.
• Grouped table — Rows grouped by class with headers for quick scanning.
• Expandable API details — Click a row (or the chevron) to open usage guidance for REST and HTTP APIs, plus an MDN reference link.
• No sign-up — Reference is static; runs entirely in your browser.

How to use

1. Open the table — Scroll the list above or use search to narrow the rows.
2. Search — Type a code (e.g. 302), a phrase, part of a name (e.g. "Forbidden"), or keywords from the API notes (e.g. "rate limit").
3. Filter by class — Choose a class from the dropdown to hide other groups.
4. Read the description — Use the third column to understand typical meaning and when the code applies.
5. Expand for API notes — Click the row to open "For APIs" guidance, bullet tips when present, and the MDN link for full spec context.

Use cases

Best practices

• Prefer specific codes — Use the narrowest correct code (e.g. 409 Conflict vs generic 400) when designing APIs.
• Don’t rely on status alone — Error bodies (JSON problem details, messages) are still important for clients.
• Distinguish 401 vs 403 — Authentication vs authorization; both are common in 4xx ranges.

Common mistakes

• Treating every 4xx as “bug” — Many 4xx codes are expected (e.g. 404 when a resource is missing). The client may need to change the request.
• Ignoring redirects — 3xx responses may require following the Location header or updating URLs.
• Caching and status — Browsers and CDNs cache differently per status; 5xx errors often should not be cached long-term.

FAQ

Related terms

This tool is commonly searched as http status codes, status code list, http 200, 404 meaning, 500 error, rest api status codes, response codes, http status codes list, http error codes, and status code reference. It helps you interpret API and browser responses quickly.

Similar tools

You might also find these developer tools useful:

• curl Converter
• URL Inspector
• JSON Formatter
• JWT Decoder

Conclusion

This HTTP status codes reference gives you a searchable, filterable status code list for APIs and debugging. Use it alongside curl → code, the URL Parser, and the JSON Formatter when building or inspecting HTTP workflows.