What does HTTP/1.1 302 mean exactly?

Learn what does http/1.1 302 mean exactly? with practical examples, diagrams, and best practices. Covers http, http-redirect, http-headers development techniques with visual explanations.
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Understanding HTTP/1.1 302 Found: The Temporary Redirect

Illustration of a web browser being redirected to a different server or page, symbolizing an HTTP 302 status.

Explore the HTTP 302 status code, its implications for web requests, and how it differs from other redirects. Learn about its use cases and best practices.

When you navigate the web, your browser constantly communicates with servers using HTTP (Hypertext Transfer Protocol). These communications involve requests from your browser and responses from the server. Each server response includes a numeric status code, indicating the outcome of the request. Among these, the 3xx series signifies redirection. Specifically, the HTTP/1.1 302 Found status code is a common, yet sometimes misunderstood, signal that the requested resource has been temporarily moved to a different URI.

What Does HTTP 302 Mean?

The HTTP 302 Found status code indicates that the resource requested by the client has been temporarily moved to a different URI. The server expects the client (typically a web browser) to automatically redirect its request to the new location provided in the Location header of the response. This redirection is considered 'temporary' because the server implies that the client should continue to use the original URI for future requests, as the resource might eventually return to its original location or move again.

Historically, the HTTP/1.0 specification defined 302 Moved Temporarily. However, HTTP/1.1 introduced 302 Found to clarify that the client should not change the request method (e.g., from POST to GET) when following the redirect, although many clients historically did. For scenarios where a method change is explicitly desired (e.g., POST to GET), 303 See Other was introduced. For permanent redirects, 301 Moved Permanently is the appropriate choice.

sequenceDiagram
    participant Client
    participant Server

    Client->>Server: GET /old-resource
    Server-->>Client: HTTP/1.1 302 Found
    Server-->>Client: Location: /new-temporary-resource
    Client->>Server: GET /new-temporary-resource
    Server-->>Client: HTTP/1.1 200 OK
    Server-->>Client: (Content of new resource)

Sequence diagram illustrating a client-server interaction with an HTTP 302 redirect.

Key Characteristics and Use Cases

The 302 Found redirect is characterized by its temporary nature and the expectation that the client will follow the Location header. Here are some common use cases:

  • Temporary Page Relocation: When a page is undergoing maintenance, or a specific version is temporarily unavailable, a 302 can direct users to an alternative, temporary page.
  • Post-Form Submission Redirects (PRG Pattern): After a user submits a form (e.g., creating an account, placing an order), a 302 redirect can send them to a confirmation page. This prevents duplicate form submissions if the user refreshes the page.
  • Load Balancing/A/B Testing: Directing users to different server instances or different versions of a page for testing purposes.
  • Session Management: Redirecting unauthenticated users to a login page, or after a successful login, redirecting them to their intended destination.

It's crucial to understand that search engines generally treat 302 redirects differently from 301s. While 301s pass most of the SEO value (link equity) to the new URL, 302s typically do not, as they signal a temporary move. This means the original URL retains its SEO authority.

HTTP/1.1 302 Found
Location: https://www.example.com/new-temporary-page
Content-Type: text/html; charset=utf-8
Content-Length: 123

<!DOCTYPE html>
<html>
<head><title>Found</title></head>
<body>
<h1>Found</h1>
<p>The document has moved <a href="https://www.example.com/new-temporary-page">here</a>.</p>
</body>
</html>

Example HTTP response headers for a 302 Found status.

Distinguishing 302 from Other Redirects

Understanding the nuances between 302 Found and other 3xx status codes is vital for correct web development and SEO. The primary distinction lies in the permanence of the redirection and the expected behavior of the client regarding the HTTP method.

  • 301 Moved Permanently: Indicates that the resource has been permanently assigned a new URI. Clients should update their links and future requests should go directly to the new URI. Search engines transfer link equity.
  • 303 See Other: Similar to 302, but explicitly states that the client should perform a GET request to the new URI, regardless of the original request method. This is often used after a POST request to prevent re-submission issues.
  • 307 Temporary Redirect: Introduced in HTTP/1.1 as a stricter version of 302. It explicitly forbids the client from changing the HTTP method when redirecting. If the original request was POST, the redirected request must also be POST. This addresses the ambiguity of 302's historical implementation.
  • 308 Permanent Redirect: The permanent counterpart to 307. It explicitly forbids changing the HTTP method, similar to 307, but for a permanent move. This is the stricter, method-preserving version of 301.

In modern web development, 307 Temporary Redirect is often preferred over 302 Found when method preservation is critical, as it removes the ambiguity that historically plagued 302 implementations. However, 302 remains widely used and understood by most clients.