HTTP Status Code Lookup

What this tool does

This http status code lookup searches a static table that ships with the page. Each row has a code, the reason phrase, a class such as 2xx Successful or 4xx Client error, and one sentence of meaning. The search box matches a code or words from the reason, the class, or that sentence.

A query that is exactly three digits is an exact code lookup. If that code is in the table, you get one row. If it is not, the status says the code is not in this list and that no description was invented. The page will not sketch a meaning for 419, 499, or any other number that was left out. A shorter query, or a phrase such as “not found” or “gateway”, searches the text of the rows and can return more than one match.

There is no API and no remote lookup. The script does not call fetch. The list is the common registered codes you meet in ordinary HTTP and WebDAV work, including the teapot code 418 with a meaning that points at RFC 2324 and says it is not a general client error. Deprecated 305 is included and labeled deprecated. Unofficial codes that never made the registry are omitted on purpose.

The tool is the content. This page is not an encyclopedia article, and it does not grow a second essay under each code. If you need a tutorial about caching or authentication, that is a different document. Here you get the row.

How to use

1. Type a code, such as 204, or a phrase, such as gateway timeout.
2. Choose Look up, or press Enter in the field.
3. Read the table. Copy writes the visible rows as text. Clear empties the field and the table.

Empty input asks you to enter a code or a phrase. The limit is 200 characters, which is far longer than a reason phrase. Results are text in table cells. A search string that looks like markup is not rendered as HTML.

Example

200 returns OK in the successful class. 301 and 302 are redirection rows with different permanence. 404 is Not Found. 500 is Internal Server Error. Searching for “timeout” can match both the client request timeout and the gateway timeout, because both reason phrases contain that word. Searching for 419 returns the unknown-code error.

404

Class is a bucket: informational, successful, redirection, client error, or server error. It is not a promise about what your framework will do. A 404 from one server and a 404 from another can wrap different bodies. The reason phrase is the registered phrase, not whatever string a proxy invented.

Limits

• Local table only. No network.
• Exact three-digit lookup, or a text search of the rows that exist.
• Unknown codes stay unknown.
• One sentence of meaning. Not an article.

The table follows the reason phrases in current HTTP for the codes it includes. Where an older phrase is still widely remembered, the row uses the registered phrase. 413 is Content Too Large. 422 is Unprocessable Content. If a book on your desk still says Payload Too Large or Unprocessable Entity, it is talking about the same numbers with the older names.

WebDAV codes such as 207, 422’s neighbors 423 and 424, and 507 are in the list because they are registered, with a short note that they come from WebDAV. They are not padded with extra tutorial text.

This lookup is not linked to every other developer tool. A status code is not a URL encoding, a UUID, or a JWT. Use it when you have a number or a phrase. Leave it when you do not.

Nothing you type is stored. Clear removes the query and the rows. A later search starts from the same static table, not from your previous query.