Beyond 200, 404, and 500: Exploring Lesser-Known HTTP Status Codes
Tags: webdev, programming, api, discuss
Published: 2023-06-23 17:15:46

Recently, while troubleshooting an issue with a third-party API, I came across an HTTP status code that I hadn't seen in a while. Beyond the commonly seen 200 (OK), 404 (Not Found), or 500 (Internal Server Error), this was one of the lesser-known ones and it got me interested. So, I decided to look into other articles about uncommon status codes. In this article, I'd like to share some of these that I haven't used a lot myself.

- **202 (Accepted):** Indicates that a request has been received and understood but is not immediately acted upon, typically useful for asynchronous tasks.

- **204 (No Content):** Often used in DELETE operations, this status code denotes a successful request that doesn't require a further response.

- **205 (Reset Content):** Instructs the client to reset its document view, potentially useful when resetting a user interface.

- **206 (Partial Content):** If only part of the resource is sent, following a range header from the client, this status code is employed, typically useful for handling large files.

- **207 (Multi-Status):** This is leveraged to provide multiple independent responses for a single request, primarily utilized in Web Distributed Authoring and Versioning (WebDAV).

- **226 (IM Used):** This status code indicates that the server has fulfilled a GET request for the resource, and the response is a representation of the result of one or more instance-manipulations applied to the current instance. It's useful when the client has applied a series of range requests, with the 226 status code indicating that the entire set has been fulfilled.

- **301 (Moved Permanently):** Announces that a resource's URL has permanently changed, proving essential during URL restructuring or website migration.

- **304 (Not Modified):** A boon for efficient caching, this status code informs the client that the cached version of the response is still valid.

- **307 (Temporary Redirect):** Indicates a temporary relocation of the resource, suggesting clients to continue using the original URL for future requests.

- **409 (Conflict):** Signifies a conflict in request parameters, such as simultaneous updates on a single resource from different clients.

- **418 (I'm a teapot):** While a humorous Easter egg from 1998, it's used by some APIs for rate limiting.

- **422 (Unprocessable Entity):** Indicates that the server can't process the request, despite understanding its syntax, commonly encountered in RESTful APIs and WebDAV.

- **429 (Too Many Requests):** This status code is used to implement rate limiting, thereby preventing potential server overload.

- **451 (Unavailable For Legal Reasons):** Servers resort to this status code to deny access to resources due to legal demands.

These are just a few of the numerous status codes defined in HTTP. However, not all of them make their way into everyday use, while others remain hidden in specific scenarios or API documentation. If you've come across an unusual status code in your development journey or have a particular one that you find intriguing, I would love to hear about it. Please share your experiences in the comments.